ASB clinical biomechanics award winner 2006 prospective study of the biomechanical factors associated with iliotibial band syndrome

Movement Quality Assessment of Army Reserve Officers' Training Corps Cadets: A Report of Validity and Normative Data

INTRODUCTION

Movement quality screening in early-career military populations, like Army Reserve Officers' Training Corps (AROTC) cadets, could decrease the negative impact of musculoskeletal injury observed within the military. Movement quality screening techniques should be valid before being pursued in the field. Normative data describing movement quality of AROTC cadets are also needed. Therefore, the aims of this study were to determine criterion validity of several movement quality assessments and report normative jump-landing kinematics of AROTC cadets.

MATERIALS AND METHODS

This cross-sectional research was approved by the Institutional Review Board. As part of a larger study, 20 AROTC cadets (21.3 ± 3.4 years; 1.7 ± 0.1 m; 73.8 ± 14.8 kg) had 3-dimensional (3D) and 2-dimensional (2D) kinematic data collected simultaneously while performing a jump-landing task. Variables of interest were 3D hip and knee sagittal, frontal, and transverse joint angles at maximum knee flexion. An experienced rater calculated sagittal and frontal 2D joint angles at maximum knee flexion. Averages of 2D and 3D angles were calculated to describe normative data and for further data analysis. Bivariate correlations between 3D and 2D variables were used to determine criterion validity.

RESULTS

Moderate correlations were found between 2D and 3D hip frontal plane angles (P = .05, r =-0.33), 2D and 3D knee sagittal plane angles (P = .04, r = 0.35), and 2D and 3D knee frontal plane angles (P = .03, r = -0.36). Normative values of knee and hip kinematics demonstrated averages of 17.58° of knee adduction, 16.48° of knee external rotation, 11.57° of hip abduction, 10.76° of hip internal rotation, and 103.47° of knee flexion during landings. However, ranges demonstrated that landing patterns vary within AROTC cadets.

CONCLUSIONS

The normative values of 3D jump-landing kinematic data indicate that movement quality varies greatly within AROTC cadets, and some cadets display potentially injurious movements. Therefore, screening movement quality could be beneficial to determine musculoskeletal injury risk in AROTC cadets. Based on the correlations discovered in this study, we recommend the 2D techniques used in this study be researched further as they may serve as alternatives to expensive, timely 3D techniques that could be better utilized in military environments.

Effect of Strength and Plyometric Training on Kinematics in Female Novice Runners

ABSTRACT

Harrison, K, Williams, DSB III, Darter, BJ, Zernicke, RF, Shall, M, and Finucane, S. Effect of strength and plyometric training on kinematics in female novice runners. J Strength Cond Res 38(6): 1048-1055, 2024-Both running performance and injury have been associated with running kinematics. Plyometric training improves run performance and reduces injury risk in court-sport and field-sport athletes. The aim of this study was to assess longitudinal changes in kinematics in novice runners before and after a typical beginners' running program, compared with those who perform a plyometric intervention before running. Fifty-seven novice female runners were assigned to the control group (8 weeks walking +8 weeks running) or the intervention group (8 weeks strength or plyometric training +8 weeks running). Kinematics were assessed at baseline, 8 weeks, and 16 weeks. Joint angles throughout the stride of those who completed the training ( n = 21) were compared between groups and assessment time points using a statistical parametric mapping 2-way analysis of variance, with group and study time point as independent variables. There was no interaction effect of group and study time point ( p > 0.05), indicating that both training programs had similar effects on running kinematics. There was a main effect of time for sagittal plane knee and hip kinematics ( p < 0.001); after training, subjects ran with a more extended leg, particularly during swing. Programs of 8 weeks of preparatory training, followed by 8 weeks of running, resulted in altered sagittal plane biomechanics, which have previously been related to improved running economy. A greater volume of plyometric, run training or concurrent plyometric and run training may be required to elicit changes in running form associated with lower injury risk.

Risk factors associated with a history of iliotibial band syndrome (hITBS) in distance runners: a cross-sectional study in 76 654 race entrants - a SAFER XXXIII study

BACKGROUND

Despite the numerous health benefits of distance running, it is also associated with the development of 'gradual onset running-related injuries' (GORRIs) one of which is Iliotibial Band Syndrome (ITBS). Novel risk factors associated with a history of ITBS (hITBS) have not been described in a large cohort of distance runners.

OBJECTIVE

To identify risk factors associated with hITBS in distance runners.

DESIGN

Descriptive cross-sectional study.

SETTING

21.1 km and 56 km Two Oceans Marathon races (2012-2015).

PARTICIPANTS

106 743 race entrants completed the online pre-race medical screening questionnaire. A total of 1 314 runners confirmed an accurate hITBS diagnosis.

METHODS

Selected risk factors associated with hITBS explored included: demographics (race distance, sex, age groups), training/running variables, history of existing chronic diseases (including a composite chronic disease score) and history of any allergy. Prevalence (%) and prevalence ratios (PR; 95% CI) are reported (uni- & multiple regression analyzes).

RESULTS

1.63% entrants reported hITBS in a 12-month period. There was a higher (p < 0.0001) prevalence of hITBS in the longer race distance entrants (56 km), females, younger entrants, fewer years of recreational running (PR = 1.07; p = 0.0009) and faster average running speed (PR = 1.02; p = 0.0066). When adjusted for race distance, sex, age groups, a higher chronic disease composite score (PR = 2.38 times increased risk for every two additional chronic diseases; p < 0.0001) and a history of allergies (PR = 1.9; p < 0.0001) were independent risk factors associated with hITBS.

CONCLUSION

Apart from female sex, younger age, fewer years of running and slower running speed, two novel independent risk factors associated with hITBS in distance runners are an increased number of chronic diseases and a history of allergies. Identifying athletes at higher risk for ITBS can guide healthcare professionals in their prevention and rehabilitation efforts.

In-vivo 3-dimensional spine and lower body gait symmetry analysis in healthy individuals

Background

Numerous research studies have delved into the biomechanics of walking, focusing on the spine and lower extremities. However, understanding the symmetry of walking in individuals without health issues poses a challenge, as those with normal mobility may exhibit uneven movement patterns due to inherent functional differences between their left and right limbs. The goal of this study is to examine the three-dimensional kinematics of gait symmetry in the spine and lower body during both typical and brisk overground walking in healthy individuals. The analysis will utilize statistical methods and symmetry index approaches. Furthermore, the research aims to investigate whether factors such as gender and walking speed influence gait symmetry.

Methods

Sixty young adults in good health, comprising 30 males and 30 females, underwent motion capture recordings while engaging in both normal and fast overground walking. The analysis focused on interlimb comparisons and corresponding assessments of side-specific spine and pelvis motions.

Results

Statistical Parametric Mapping (SPM) predominantly revealed gait symmetries between corresponding left and right motions in the spine, pelvis, hip, knee, and ankle during both normal and fast overground walking. Notably, both genders exhibited asymmetric pelvis left-right obliquity, with women and men showing an average degree of asymmetry between sides of 0.9 ± 0.1° and 1.5 ± 0.1°, respectively. Furthermore, the analysis suggested that neither sex nor walking speed appeared to exert influence on the 3D kinematic symmetry of the spine, pelvis, and lower body in healthy individuals during gait. While the maximum normalized symmetry index (SInorm) values for the lower thorax, upper lumbar, lower lumbar, pelvis, hip, knee, and ankle displayed significant differences between sexes and walking speeds for specific motions, no interaction between sex and walking speed was observed.

Significance

The findings underscore the potential disparities in data interpretations between the two approaches. While SPM discerns temporal variations in movement, these results offer valuable insights that may enhance our comprehension of gait symmetry in healthy individuals, surpassing the limitations of straightforward discrete parameters like the maximum SInorm. The information gleaned from this study could serve as reference indicators for diagnosing and evaluating abnormal gait function.

What is the influence of biomechanical variables on the Y balance test performance in recreational runners?

BACKGROUND

Asymmetries and poor Y balance test (YBT) performance are associated with an increased risk of injuries in athletes. The aim of this study was to investigate the association between YBT performance with biomechanical variables in runners.

METHODS

The runners underwent the YBT, followed by the assessment of center of pressure, plank position, muscle strength (MS) of hip flexors, extensors, abductors, and external rotators, knee extensors, ankle dorsiflexion range of motion (ROM), Q angle, forefoot alignment, and passive hip internal rotation. Associations between variables were examined using multiple linear regression models with the Bayesian Information Criterion.

RESULTS

122 cases were analyzed. The R2 values were 0.38; 0.05; 0.06; and 0.15 for the anterior, posteromedial, posterolateral and composite directions models, respectively. The anterior reach in the YBT was associated with ankle dorsiflexion ROM [Sβ 95%IC: 0.43 (0.32-0.55)], passive hip internal rotation [Sβ 95%IC: 0.35 (0.24-0.47)], MS of the hip extensors [Sβ 95%IC: 0.19 (0.07-0.31)] and forefoot alignment [Sβ 95%IC: 0.14 (-0.25-0.02)]. The posteromedial and posterolateral reach were associated with MS of the hip flexors [Sβ 95%IC: 0.23 (0.09-0.37) and 0.24 (0.11-0.38)], respectively. The composite score was associated with MS of the hip flexors [Sβ 95%IC: 0.31 (0.18-0.45)], ankle dorsiflexion ROM [Sβ 95%IC: 0.24 (0.10-0.37)] and Q angle [Sβ 95%IC: 0.18 (0.04-0.31)].

CONCLUSION

YBT performance in different directions demonstrated specific associations with key biomechanical factors.

Running Gait Training Improves Outcomes at United States Air Force Basic Military Training

INTRODUCTION

The aim is to investigate the impact of large-group, motor learning-based running gait training on injury risk in United States Air Force (USAF) Basic Military Training (BMT).

DESIGN

A prospective quasi-experimental program evaluation is used.

MATERIALS AND METHODS

Medical providers taught running gait form to groups of trainees in the first week of training of BMT from August 2020 to March 2021. The main outcome measures included risk ratio of reported injuries, removal from training because of injury, and separation from service because of injury.

RESULTS

Of BMT trainees, 2,205 underwent group, motor learning-based running gait training; this was compared with two intake groups (nA = 3,941 and nB = 2,041) who were only given introductions to sports medicine staff in a classroom setting. Reported pain complaints increased (χ2 = 27.4A and 20.83B, P < .001). Risk ratios for more severe injuries necessitating time out of training or separation from USAF were reduced, although these were statistically not significant (13%, P = .48 and 22%, P = .29, respectively). Leadership implemented gait training across BMT, and data from the following 8 weeks of intake (n = 6,223) demonstrated similar trends in increases in patient reports of pain (χ2 = 67.25, P < .001) but significantly reduced risk ratios of removal from training (32%, χ2 = 16.35, P < .001) or separation (32%, χ2 = 12.54, P < .001).

CONCLUSIONS

While not previously shown to mitigate injury, large-group, running gait training was associated with a significant reduction in injury severity defined by training delays and separation from service in USAF BMT.

Running intralimb coordination patterns after a foot core exercise program in recreational runners

This study investigated the effects of a foot core intervention on the coordination of foot joints in recreational runners. This was a secondary analysis from a randomized controlled trial conducted with 87 recreational runners allocated to the control group (CG), which followed a placebo lower limb stretching protocol, or the intervention group (IG), which underwent an 8-week (3 times/week) foot core training. The participants ran on a force-instrumented treadmill at a self-selected speed (9.5-10.5 km/h) while the foot segment motion was captured. The vector coding technique was used to assess inter-joint coordination for four selected coupled segment and joint angles. The coordination patterns of the calcaneus and midfoot (CalMid) and midfoot and metatarsus (MidMet) joint pairs were affected. In the frontal plane, IG showed an in-phase with proximal dominancy coordination at heel strike, with a decrease in its frequency after the training (P=0.018), suggesting a longer foot supination. Additionally, IG showed an anti-phase with distal dominancy pattern at early stance compared to CG due to a smaller but earlier inversion of the CalMid-MidMet pair (P=0.020). The intervention also had an effect on the transverse plane of the CalMid-MidMet pair, with IG showing a significantly greater frequency of anti-phase coordination with proximal dominancy during propulsion than CG (P=0.013), probably due to a reduction in the CalMid abduction. Overall, the results suggested that the foot core intervention reduces the occurrence of running-related injuries by increasing the resistance to calcaneus pronation and building a more rigid and efficient lever during push-off.

The effects of alteration in muscle activation on the iliotibial band during an exhaustive run

PURPOSE

Long exhausted running causes pain at the lateral femoral epicondyle for some runners. The pain has been revealed to be related to the behavior of the iliotibial band (ITB) during running. The purpose of this study is to examine the effects of in-series musculature on the behavior of the ITB in healthy participants during an exhaustive run.

METHODS

Twenty-five healthy participants (15 males, 10 females) were recruited in the current study. All participants performed a 30-minute exhaustive run at a self-selected speed with laboratory-provided footwear. Muscle activities of ITB-related muscles including tensor fascia latae (TFL), gluteus maximus (Gmax), gluteus medius (Gmed), biceps femoris (BF), and vastus lateralis (VL) were recorded using surface electromyography (EMG).

RESULTS

Maximum amplitudes at the initial stage (the first minute), the mid stage (the 15-minute), and the end stage (the 30-minute) were compared during the exhaustive running. Significant decreases (p < 0.05) were observed in the maximum amplitudes of the TFL, Gmax, Gmed, and BF at the mid (decreased by ~ 15%) and end (decreased by ~ 30%) stages compared to the initial stage. The onset and the offset remained unaltered during the running (p ≥ 0.05).

CONCLUSION

The behavior of the healthy ITB might be altered due to the activities of the in-series musculature. Excessive compression forces might be applied to the lateral femoral epicondyle from the ITB to provide stability for the knee joint during an exhaustive run. The findings could provide a basic understanding of the behavior of healthy ITB.

The Association of Joint Power Kinetic Variables with Running Injuries: A Case-Control Study

Background

There is conflicting data on which kinetic variables are important to consider with running injuries. Furthermore, less is understood regarding differences in these variables when considering demographics such as age, sex, weight, and running speed. The primary question was what joint power kinetic variables were different between non-injured and injured runners.

Purpose

The purpose of this study was to identify if there were differences in joint power kinetic variables between non-injured runners and injured runners.

Study Design

Case-Control Study.

Methods

Kinetic data were collected on 122 runners (26 non-injured and 96 injured) over three years with a Bertec force plated treadmill and Qualisys 3D motion capture. The subjects were considered eligible if they self-identified themselves as runners or had running as a key component of their activity. The subjects ran at a comfortable, self-selected pace while two 10-second trials of recordings were used to calculate the means of peak power generated at the hips, knees, and ankles of each gait cycle. Foot strike was categorized by kinematic data. Two sample T-tests were used to compare peak power variables at the hips, knees, and ankles between non-injured and injured runners. Logistic regression analyses examined how a combination of demographics and peak power variables were associated with injuries.

Results

No peak power variable at the hip, knee, or ankle was significantly different between injured and non-injured runners (p=0.07-0.87). However, higher hip power absorbed was found to be protective against injuries (odds ratio, .16; 95% CI .025-.88) when considering demographics using a logistic regression model including sex, foot strike, BMI, speed, age, and power variables from the hip, knee, and ankle. The area under the ROC curve was .74, which is acceptable discrimination.

Conclusion

When controlling for age, sex, BMI, foot strike, and speed; higher hip power absorbed was found to be protective against injury. This could be due to the hip muscles' unique role in absorbing force during early stance phase.

Level of Evidence

3b©The Author(s).

Validity and reliability of two-dimensional video-based assessment to measure joint angles during running: A systematic review and meta-analysis

Two-dimensional video analysis systems (2DVAS) are commonly used by clinicians and researchers to determine angles during running. The aim of this systematic review (PROSPERO: CRD42022322798) was to synthesize the literature on the criterion validity and reliability of 2DVAS for measuring angles during running compared to three-dimensional motion analysis systems (3DMAS). We searched for articles on MEDLINE/Pubmed, EMBASE, SciELO, and LILACS up to October/2022. We included studies that evaluated the validity of 2DVAS (when compared to 3DMAS) and/or the reliability of 2DVAS measurements of lower limb and trunk angles during running. Qualitative and quantitative analyses were performed. Seven hundred and five studies were found and 17 were included. Ten studies analysed criterion validity between 2DVAS and 3DMAS and the results ranged from poor to excellent, with most of the parameters assessed presenting poor or moderate validity. Inter-rater reliability of 2DVAS was assessed in nine studies and most of the parameters investigated had good to excellent reliability. Intra-rater reliability (between-day processing) of angular running parameters - investigated in ten studies - was considered excellent for most of the parameters analysed. Inter-session reliability was assessed in three studies and was defined as good or excellent for most of the variables assessed. 2DVAS is a reliable method for measuring joint angles during running. However, the validity of 2DVAS compared to 3DMAS ranges from low to moderate for most running parameters. Therefore, based on the available evidence, caution should be taken when applying 2DVAS, particularly for frontal and transverse plane angles.

Are alterations in running biomechanics associated with running injuries? A systematic review with meta-analysis

BACKGROUND

No systematic review has investigated the main biomechanical variables as predictors of running-related injuries.

OBJECTIVE

To investigate the main biomechanical variables associated with running-related injuries.

METHODS

Medline via PubMed, EMBASE, SPORTDiscus, Web of Science, and CINAHL were searched from inception until 1 November 2021. Each study included must have investigated the association of at least one biomechanical variable (kinetics, kinematics, electromyography, or pressure distribution) with running injuries. The meta-analysis was conducted, and a modified version of the Downs and Black Quality Index was used for methodological quality evaluation.

RESULTS

Across the 82 studies included, 5465 runners were investigated. The meta-analysis was conducted with 11 biomechanical variables from 51 articles (n=2395). The peak hip adduction angle was the sole biomechanical variable associated with running injury and was found to be higher in injured runners (0.57, 95% CI 0.21, 0.94) compared to uninjured runners. However, this result was highly influenced by two studies (out of five studies) conducted by the same group of authors.

CONCLUSION

Clinicians, coaches, and runners should be aware that minimal evidence supports that alterations of running biomechanics are associated with running-related injuries. Heterogeneity in evaluation conditions and inconsistency in the naming and definitions of biomechanical variables make definitive conclusions challenging.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO, CRD42017068839.

Aetiological Factors of Running-Related Injuries: A 12 Month Prospective "Running Injury Surveillance Centre" (RISC) Study

BACKGROUND

Running-related injuries (RRIs) are a prevalent issue for runners, with several factors proposed to be causative. The majority of studies to date are limited by retrospective study design, small sample sizes and seem to focus on individual risk factors in isolation. This study aims to investigate the multifactorial contribution of risk factors to prospective RRIs.

METHODS

Recreational runners (n = 258) participated in the study, where injury history and training practices, impact acceleration, and running kinematics were assessed at a baseline testing session. Prospective injuries were tracked for one year. Univariate and multivariate Cox regression was performed in the analysis.

RESULTS

A total of 51% of runners sustained a prospective injury, with the calf most commonly affected. Univariate analysis found previous history of injury < 1 year ago, training for a marathon, frequent changing of shoes (every 0-3 months), and running technique (non-rearfoot strike pattern, less knee valgus, greater knee rotation) to be significantly associated with injury. The multivariate analysis revealed previous injury, training for a marathon, less knee valgus, and greater thorax drop to the contralateral side to be risk factors for injury.

CONCLUSION

This study found several factors to be potentially causative of injury. With the omission of previous injury history, the risk factors (footwear, marathon training and running kinematics) identified in this study may be easily modifiable, and therefore could inform injury prevention strategies. This is the first study to find foot strike pattern and trunk kinematics to relate to prospective injury.

Stretching and Releasing of Iliotibial Band Complex in Patients with Iliotibial Band Syndrome: A Narrative Review

Iliotibial band syndrome (ITBS) is one of the most common overuse syndromes causing knee pain; it is especially prevalent in runners and also common in cyclists, rowers, and field athletes, with occasional cases occurring in non-athletes too. ITBS symptoms can negatively affect not only knee function, but also mental and physical aspects of health-related quality of life. Although various conservative treatment options have been investigated and discussed, there is still no consensus on a standard of care for ITBS. Moreover, the literature on the etiology and risk factors of ITBS, which could help in selecting appropriate treatment methods, is conflicting and inconclusive. The role of individual treatment modalities such as stretching and releasing techniques has not been extensively studied and remains unclear. In this article, we will critically review the available evidence for the benefits of ITB stretching and "release" methods in the treatment of ITBS. In addition to the direct evidence (clinical studies examining the effects of ITB stretching and other methods that purportedly stretch or "release" the ITB), we present several additional lines of reasoning that discuss the rationale for ITB stretching/releasing in terms of the etiology of ITBS, the mechanical properties and behavior of the ITB, and the risk factors for ITBS development. We conclude that the current literature provides some evidence for the inclusion of stretching or other "release" methods in the early rehabilitation of ITBS. Long-term interventions typically include ITB stretching; however, it remains unclear to what extent stretching within a multimodal treatment actually contributes to resolving the symptoms. At the same time, there is no direct evidence to suggest that stretching and "release" methods have any negative effects.

Impact of biomechanics on therapeutic interventions and rehabilitation for major chronic musculoskeletal conditions: A 50-year perspective

The pivotal role of biomechanics in the past 50 years in consolidating the basic knowledge that underpins prevention and rehabilitation measures has made this area a great spotlight for health practitioners. In clinical practice, biomechanics analysis of spatiotemporal, kinematic, kinetic, and electromyographic data in various chronic conditions serves to directly enhance deeper understanding of locomotion and the consequences of musculoskeletal dysfunctions in terms of motion and motor control. It also serves to propose straightforward and tailored interventions. The importance of this approach is supported by myriad biomechanical outcomes in clinical trials and by the development of new interventions clearly grounded on biomechanical principles. Over the past five decades, therapeutic interventions have been transformed from fundamentally passive in essence, such as orthoses and footwear, to emphasizing active prevention, including exercise approaches, such as bottom-up and top-down strengthening programs for runners and people with osteoarthritis. These approaches may be far more effective inreducing pain, dysfunction, and, ideally, incidence if they are based on the biomechanical status of the affected person. In this review, we demonstrate evidence of the impact of biomechanics and motion analysis as a foundation for physical therapy/rehabilitation and preventive strategies for three chronic conditions of high worldwide prevalence: diabetes and peripheral neuropathy, knee osteoarthritis, and running-related injuries. We conclude with a summary of recommendations for future studies needed to address current research gaps.

Effects of Running Speeds and Exhaustion on Iliotibial Band Strain during Running

Background: Iliotibial band syndrome (ITBS) is one of the most prevalent overuse injuries in runners. The strain rate in the iliotibial band (ITB) has been theorized to be the primary causative factor in the development of ITBS. Running speed and exhaustion might lead to an alteration in the biomechanics that influence the strain rate in the iliotibial band. Objectives: To identify how exhaustion states and running speeds affect the ITB strain and strain rate. Methods: A total of 26 healthy runners (including 16 males and 10 females) ran at a normal preferred speed and a fast speed. Then, participants performed a 30 min exhaustive treadmill run at a self-selected speed. Afterward, participants were required to run at similar speeds to those of the pre-exhaustion state. Results: Both the exhaustion and running speeds were revealed to have significant influences on the ITB strain rate. After exhaustion, an increase of approximately 3% in the ITB strain rate was observed for both the normal speed (p = 0.001) and the fast speed (p = 0.008). Additionally, a rapid increase in the running speed could lead to an increase in the ITB strain rate for both the pre- (9.71%, p = 0.000) and post-exhaustion (9.87%, p = 0.000) states. Conclusions: It should be noted that an exhaustion state could lead to an increase in the ITB strain rate. In addition, a rapid increase in running speed might cause a higher ITB strain rate, which is proposed to be the primary cause of ITBS. The risk of injury should also be considered due to the rapid increase in the training load involved. Running at a normal speed in a non-exhaustive state might be beneficial for the prevention and treatment of ITBS.

Lower extremity kinematics during running and hip abductor strength in iliotibial band syndrome: A systematic review and meta-analysis

BACKGROUND

Iliotibial band syndrome is a common overuse injury that is twice as likely to affect female runners compared to male runners. It is unclear if there is a consistent running pattern and strength profile exhibited by female and male runners with iliotibial band syndrome.

RESEARCH QUESTION

The purpose of this systematic review and meta-analysis was to determine if any differences existed in lower-extremity kinematics and hip strength between runners who retrospectively, currently, or prospectively had iliotibial band syndrome.

METHODS

Papers included must have reported three-dimensional kinematic running data and/or hip strength data that were statistically analyzed between runners that never developed iliotibial band syndrome and runners with iliotibial band syndrome. Meta-analysis was performed for each kinematic or strength variable reported in at least three studies. Female and male runners were analyzed separately and grouped into three cohorts (retrospective, current, prospective).

RESULTS

Seventeen articles were included in this systematic review. Data from 10 cross-sectional studies were included for meta-analysis. Female runners with current iliotibial band syndrome exhibited smaller peak hip internal rotation angles and lower isometric hip abductor strength compared to controls.

SIGNIFICANCE

Although limited biomechanical evidence exists, risk factors for ITBS are different between female and male runners and may vary according to injury status. Specifically, transverse plane hip motion and hip abductor strength weakness may be biomechanical risk factors in female runners with current iliotibial band syndrome only.

Electromyographic analysis of the three subdivisions of gluteus medius during two different exercises: Wall press exercise and figure-of-four position

BACKGROUND

Gluteus medius (GM) is a segmented muscle involving three muscular subdivisions. Rehabilitation exercises has been suggested to strengthen specific subdivisions.

OBJECTIVE

This study aimed to evaluate muscular activation of the anterior, middle, and posterior subdivisions of the GM during two different exercises.

METHODS

A total of 28 healthy active subjects participated in this study. Muscle activity using surface electromyography was recorded for the three GM subdivisions during figure-of-four position (FFP) and wall press (WP). Non-parametric Kruskal-Wallis test was used to detect differences between GM subdivisions on each exercise and the Mann-Whitney U test was used to compare muscular activation across exercises.

RESULTS

There were statistically significant differences (P< 0.001) in all GM subdivision during FFP and WP exercises. Both exercises showed greater activation of the posterior subdivision than the middle and anterior subdivisions, with the WP causing highest activation of the posterior subdivision.

CONCLUSION

In line with the WP exercise, the FFP produces sufficient activity to provide potential strength gains on the posterior subdivision and could be a viable option to include in the early stages of the rehabilitation process. Clinicians may use this information to make more informed decisions about exercise selection for strengthening specific GM subdivision.

Between-day reliability and minimum detectable change of the Conventional Gait Model 2 and Plug-in Gait Model during running

BACKGROUND

The Plug-in Gait model (PiG) is commonly used in 3D motion analysis but has limited reliability. Although an improved version of PiG has been developed, called the Conventional Gait Model 2 (CGM2), there is limited evidence on its between-day reliability for running.

RESEARCH QUESTION

What is the between-day intraclass correlation coefficient (ICC3,k) and minimum detectable change (MDC) of lower limb kinematics and kinetics for CGM2 during running and does reliability differ between CGM2 and PiG.

METHODS

Twenty-three healthy participants performed running at a comfortable speed in two identical test sessions at least 5 days apart. Lower limb kinematic and kinetic data in the three planes of motion were calculated using CGM2 and PiG. The ICC and MDC were calculated for the kinematic and kinetic parameters at initial contact and peak during the stance phase of running.

RESULTS

CGM2 kinematics showed good-to-excellent reliability (ICC: 0.75-0.93), except for hip extension and ankle internal rotation, and less than 5° MDC (1.8°-4.9°) of the coronal and sagittal planes, except for hip extension. PiG showed poor-to-moderate reliability (ICC: -0.15 to 0.72) in the coronal and transverse planes and greater than 5° MDC (5.0°-21.8°), except for knee extension, adduction, and ankle dorsiflexion. CGM2 showed good-to-excellent reliability for peak kinetics (ICC: 0.75-0.97), except for hip internal rotation and knee extension. The ICC and MDC were higher for CGM2 than PiG, with significant differences in the coronal plane of the hip and knee joints and transverse plane of the hip joint in kinematics and in the sagittal and coronal plane of the hip and knee joints in kinetics.

SIGNIFICANCE

The between-day reliability of CGM2 was mostly good to excellent for lower limb kinematics and kinetics during running. We believe that CGM2 can more accurately assess kinematic differences between the coronal and transverse planes than the PiG.

The Running Readiness Scale as an Assessment of Kinematics Related to Knee Injury in Novice Female Runners

CONTEXT

Frontal- and transverse-plane kinematics have been prospectively identified as risk factors for running-related injuries in females. The Running Readiness Scale (RRS) may allow for clinical evaluation of these kinematics.

OBJECTIVES

To determine the reliability and validity of the RRS as an assessment of frontal- and transverse-plane running kinematics.

DESIGN

Cross-sectional study.

SETTING

University research laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 56 novice female runners (median [interquartile range] age = 34 years [26-47 years]).

MAIN OUTCOME MEASURE(S)

We collected 3-dimensional kinematics during running and RRS tasks: hopping, plank, step-ups, single-legged squats, and wall sit. Five clinicians assessed RRS performances 3 times each. Interrater and intrarater reliabilities of the total RRS score and individual tasks were calculated using the intraclass correlation coefficient and Fleiss κ, respectively. Pearson product moment correlation coefficients between peak joint angles measured during running and the same angles measured during RRS tasks were computed. Peak joint angles of high- and low-scoring participants were compared.

RESULTS

Interrater and intrarater reliabilities of assessment of the total RRS scores were good (intraclass correlation coefficients = 0.75 and 0.80, respectively). Reliability of assessing individual tasks was moderate to almost perfect (κ = 0.58-1.00). Peak hip adduction, contralateral pelvic drop, and knee abduction during running were correlated with the same angles measured during hopping, step-ups, and single-legged squats (r = 0.537-0.939). Peak knee internal rotation during running was correlated with peak knee internal rotation during step-ups (r = 0.831). Runners who scored high on the RRS demonstrated less knee abduction during running (P ≤ .01).

CONCLUSIONS

The RRS may effectively assess knee abduction in novice runners, but evaluation criteria or tasks may need to be modified to effectively characterize pelvic and transverse-plane knee kinematics.

Validation of an Ear-Worn Wearable Gait Analysis Device

Wearable devices capable of measuring gait parameters may provide a means to more economical gait analysis compared to conventional equipment comprising of a motion capture system and a forced treadmill. Beflex Coach (Beflex, Republic of Korea) is one such device but worn on the ear as Bluetooth earphones, unlike other wearables worn on the wrist, feet, or torso. In this study, the validity of the device was examined against a motion capture system and a forced treadmill for walking and running parameters. Five walking parameters (cadence, single support time, double support time, vertical oscillation (VO), and instantaneous vertical loading rate (IVLR)) and six running parameters (cadence, stance time, flight time, peak force, VO, and IVLR) were studied. Twenty young adults participated in walking or running on a forced treadmill at different speeds (walking: 0.8, 1.25, and 1.7 m/s for walking; running: 2, 2.5, and 3 m/s) while the two systems operated simultaneously. As a result, all parameters showed excellent associations (ICC > 0.75) and good agreements in Bland-Altman plots. The results of the study support the potential use of the ear-worn device as an inexpensive gait analysis equipment.

Effectiveness of an 18-week general strength and foam-rolling intervention on running-related injuries in recreational runners

RATIONALE

More research is needed to uncover the effectiveness of combined strength and foam-rolling interventions to prevent running-related injuries.

OBJECTIVES

To evaluate effectiveness of an 18-week general strength and foam-rolling intervention on the incidence of running-related injuries.

METHOD

This is an 18-week observational comparative study. A total of 433 recreational runners participated (n = 203 female). The intervention group (n = 228) performed general strength and foam-rolling exercises twice weekly for 18 weeks, the control group (n = 205) maintained their regular training habits. Running volume and running-related pain were reported weekly. Secondary analyses were performed on the subgroups of the intervention group based on compliance; low compliance (n = 100), intermediate compliance (n = 63), and high compliance (n = 65). Cumulative incidence proportions were calculated and time-to-event statistics were performed to compare survival times between groups. Univariate cox proportional hazards ratio was calculated to estimate the risk of running-related injuries at 18 weeks.

RESULTS

A total of 100 running-related injuries were sustained. The cumulative incidence proportion for the control and intervention groups was 27.1% (95% CI: 21.4-33.9) and 23.0% (95% CI: 17.8-29.4), respectively. No statistically significant difference was found between the overall intervention group and control group (log-rank p = 0.31). A significant difference existed between the high-compliance subgroup and the control group (log-rank p = 0.00). Highly compliant runners were 85% less likely (hazard rate ratio = 0.15; 95% CI: 0.05-0.46) to sustain an injury during the study compared with controls.

CONCLUSION

Recreational runners highly compliant with the intervention were 85% less likely and took on average 57 days longer to sustain a running-related injury when compared with controls, with a cumulative incidence proportion of 4.6% after 18 weeks.

Effect of Flat Running Shoes on Hip Kinematics in Male Recreational Runners

Patellofemoral joint pain and iliotibial band syndrome are very common running-related injuries. Excessive contralateral pelvic drop, hip adduction, and hip internal rotation have been suggested to be associated with the two injuries. The purpose of this repeated measures and the cross-sectional study was to investigate the effect of flat running shoes on these kinematic variables compared with that of conventional running shoes with a 10 mm drop. Eighteen male recreational runners were recruited to run in flat shoes and conventional shoes with a 10 mm drop, in random order. Impact force data and lower extremity kinematics were synchronously obtained using two Kistler force plates and eight motion infrared cameras, whereas differences in the impact force and hip kinematics were compared using statistical parametric mapping. Regarding hip kinematics, the hip flexion (p = 0.004) and adduction angles (p = 0.004) decreased significantly at 30-70% and 62-85% of the stance phase, respectively, while wearing flat running shoes; the contralateral pelvic drop angle (p = 0.001) decreased significantly at 31-75% of the stance phase while wearing flat running shoes. The knee internal rotation angle (p = 0.035) decreased significantly at 8-17% of the stance phase while wearing flat running shoes compared with conventional running shoes. Given that these kinematic variables are associated with patellofemoral joint pain and iliotibial band syndrome, flat running shoes may have potential benefits for the prevention or treatment of knee injuries.

Is There a Correlation Between Reported Knee Pain and Fluid at the Distal Insertion of the Iliotibial Band in Runners?

Objective

To determine whether there is a correlation between pain and the amount of fluid present at the distal insertion of the iliotibial band (ITB) in runners, as measured by USG.

Method

Our retrospective cross-sectional study evaluated 100 male and female runners prior to the start of a race. A valid and reliable questionnaire collected demographic, pain, and training data. If a runner reported knee pain, a numeric pain rating scale was used to record the degree of pain. Participants then underwent USG on both knees to determine the presence or absence of fluid at the distal insertion of the ITB.

Result

We found no statistically significant correlations of fluid measurements with pain score, running experience in years, or age. In addition, we found no other differences in fluid measurements between those with and without knee pain or between the sexes.

Conclusions

Our findings indicate that the presence or absence of fluid at the distal insertion of the ITB does not correlate with knee pain in runners, regardless of age, running experience, or sex.

Loaded Functional Strength Training versus Traditional Physical Therapy on Hip and Knee Extensors Strength and Function Walking Capacity in Children with Hemiplegic Cerebral Palsy: Randomized Comparative Study

Objective: This study’s objective was to see how loaded functional strengthening exercises using a plantigrade foot position and a shoe supporter affected muscle strength and walking ability in spastic hemiplegic children. Methods: Seventy-two children with spastic hemiplegic cerebral palsy, both sexes, aged ten to twelve years, were randomly assigned into two groups equal in number (control and intervention groups). The control group received a specially designed physical therapy program, whereas the intervention group received a loaded functional strengthening exercises program using a shoe supporter to maintain a plantigrade foot position. The training program was carried out for 60 min, three times per week for three consecutive months. All participants were evaluated both before and after the therapy program by using a Medical Commander Echo Manual Muscle Tester dynamometer to assess isometric muscle power of hip and knee extensors on the affected side. To assess functional walking capacity, a 6 min walking (6MWT) test was used. Results: Study groups were comparable with respect to all outcome measures at entry (p > 0.05). Within-group comparison showed significant improvements in all measured variables. Furthermore, between-group comparison revealed significantly greater improvements (p < 0.05) in hip and knee extensors strength as well as the functional walking capacity in favor of the intervention group. Conclusions: In all the analyzed variables, loaded functional strength exercises from the plantigrade foot position were found to be considerably more effective in the intervention group than in the control group.

Gait and Neuromuscular Changes Are Evident in Some Masters Club Level Runners 24-h After Interval Training Run

Purpose

To examine the time course of recovery for gait and neuromuscular function immediately after and 24-h post interval training. In addition, this study compared the impact of different statistical approaches on detecting changes.

Methods

Twenty (10F, 10M) healthy, recreational club runners performed a high-intensity interval training (HIIT) session consisting of six repetitions of 800 m. A 6-min medium intensity run was performed pre, post, and 24-h post HIIT to assess hip and knee kinematics and coordination variability. Voluntary activation and twitch force of the quadriceps, along with maximum isometric force were examined pre, post, and 24-h post significance HIIT. The time course of changes were examined using two different statistical approaches: traditional null hypothesis significance tests and “real” changes using minimum detectable change.

Results

Immediately following the run, there were significant (P < 0.05) increases in the hip frontal kinematics and coordination variability. The runners also experienced a loss of muscular strength and neuromuscular function immediately post HIIT (P < 0.05). Individual assessment, however, showed that not all runners experienced fatigue effects immediately post HIIT. Null hypothesis significance testing revealed a lack of recovery in hip frontal kinematics, coordination variability, muscle strength, and neuromuscular function at 24-h post, however, the use of minimum detectable change suggested that most runners had recovered.

Conclusion

High intensity interval training resulted in altered running kinematics along with central and peripheral decrements in neuromuscular function. Most runners had recovered within 24-h, although a minority still exhibited signs of fatigue. The runners that were not able to recover prior to their run at 24-h were identified to be at an increased risk of running-related injury.

Effects of Foot-Core Training on Foot-Ankle Kinematics and Running Kinetics in Runners: Secondary Outcomes From a Randomized Controlled Trial

This study investigated the effectiveness of an 8-week foot-core exercise training program on foot-ankle kinematics during running and also on running kinetics (impact loads), with particular interest in biomechanical outcomes considered risk factors for running-related injuries in recreational runners. A single-blind, randomized, controlled trial was conducted with 87 recreational runners randomly allocated to either the control (CG) or intervention (IG) group and assessed at baseline and after 8 weeks. The IG underwent foot-core training 3 times/week, while the CG followed a placebo lower-limb stretching protocol. The participants ran on a force-instrumented treadmill at a self-selected speed while foot-segment motion was captured simultaneously with kinetic measurements. After the intervention, there were statistically significant changed in foot biomechanics, such as: IG participants strike the ground with a more inverted calcaneus and a less dorsiflexed midfoot than those in the CG; at midstance, ran with a less plantarflexed and more adducted forefoot and a more abducted hallux; and at push-off, ran with a less dorsiflexed midfoot and a less adducted and more dorsiflexed hallux. The IG runners also had significantly decreased medial longitudinal arch excursion (p = 0.024) and increased rearfoot inversion (p = 0.037). The 8-week foot-core exercise program had no effect on impact (p = 0.129) and breaking forces (p = 0.934) or on vertical loading rate (p = 0.537), but it was positively effective in changing foot-ankle kinematic patterns.”

Biomechanical and Musculoskeletal Measurements as Risk Factors for Running-Related Injury in Non-elite Runners: A Systematic Review and Meta-analysis of Prospective Studies

BACKGROUND

Running-related injury (RRI) is highly prevalent among recreational runners and is a key barrier to participation. Atypical lower limb alignment and mechanical function have been proposed to play a role in development of lower extremity injury. The purpose of this study was to investigate relationships between incidence of running-related injury (RRI) in non-elite runners with biomechanical and musculoskeletal variables.

METHODS

A systematic review and meta-analysis of prospective studies. Published research indexed in MEDLINE, EMBASE, CINAHL, SPORTDiscus, AMED, and The Cochrane library until 13th January 2021, grey literature, and reference lists of included studies were screened to identify prospective studies of non-elite adult runners that measured a relationship between biomechanical or musculoskeletal measures and incidence of RRI.

RESULTS

Thirty studies (3404 runners), testing over 100 discrete biomechanical and musculoskeletal risk factors for RRI, were included. Nineteen studies were pooled in twenty-five separate meta-analyses. Meta-analysis of four studies detected significantly less knee extension strength among runners who developed a RRI (SMD - 0.19, 95% CI - 0.36 to - 0.02, p = 0.03), though this may not be clinically important. A meta-analysis of two studies detected significantly lower hip adduction velocity among runners who developed a RRI (MD - 12.80, 95% CI - 25.22 to - 0.38, p = 0.04). Remaining meta-analyses found no significant relationship between biomechanical or musculoskeletal variables and RRI.

CONCLUSION

This systematic review and meta-analysis found the currently available literature does not generally support biomechanical or musculoskeletal measures as risk factors for RRI in non-elite runners. While meta-analysis findings for knee extension strength and hip adduction velocity as risk factors for RRI were statistically significant, the associated trivial to small effects sizes suggest these findings should be treated with caution. Until further evidence emerges, recommendations for injury prevention in non-elite runners cannot be made based on biomechanical and musculoskeletal measurements alone.

The Iliotibial Band: A Complex Structure with Versatile Functions

The development of a pronounced iliotibial band (ITB) is an anatomically distinct evolution of humans. The mechanical behaviour of this “new” structure is still poorly understood and hotly debated in current literature. Iliotibial band syndrome (ITBS) is one of the leading causes of lateral knee pain injuries in runners. We currently lack a comprehensive understanding of the healthy behaviour of the ITB, and this is necessary prior to further investigating the aetiology of pathologies like ITBS. Therefore, the purpose of this narrative review was to collate the anatomical, biomechanical and clinical literature to understand how the mechanical function of the ITB is influenced by anatomical variation, posture and muscle activation. The complexity of understanding the mechanical function of the ITB is due, in part, to the presence of its two in-series muscles: gluteus maximus (GMAX) and tensor fascia latae (TFL). At present, we lack a fundamental understanding of how GMAX and TFL transmit force through the ITB and what mechanical role the ITB plays for movements like walking or running. While there is a range of proposed ITBS treatment strategies, robust evidence for effective treatments is still lacking. Interventions that directly target the running biomechanics suspected to increase either ITB strain or compression of lateral knee structures may have promise, but clinical randomised controlled trials are still required.

Running-Related Biomechanical Risk Factors for Overuse Injuries in Distance Runners: A Systematic Review Considering Injury Specificity and the Potentials for Future Research

BACKGROUND

Running overuse injuries (ROIs) occur within a complex, partly injury-specific interplay between training loads and extrinsic and intrinsic risk factors. Biomechanical risk factors (BRFs) are related to the individual running style. While BRFs have been reviewed regarding general ROI risk, no systematic review has addressed BRFs for specific ROIs using a standardized methodology.

OBJECTIVE

To identify and evaluate the evidence for the most relevant BRFs for ROIs determined during running and to suggest future research directions.

DESIGN

Systematic review considering prospective and retrospective studies. (PROSPERO_ID: 236,832).

DATA SOURCES

PubMed. Connected Papers. The search was performed in February 2021.

ELIGIBILITY CRITERIA

English language. Studies on participants whose primary sport is running addressing the risk for the seven most common ROIs and at least one kinematic, kinetic (including pressure measurements), or electromyographic BRF. A BRF needed to be identified in at least one prospective or two independent retrospective studies. BRFs needed to be determined during running.

RESULTS

Sixty-six articles fulfilled our eligibility criteria. Levels of evidence for specific ROIs ranged from conflicting to moderate evidence. Running populations and methods applied varied considerably between studies. While some BRFs appeared for several ROIs, most BRFs were specific for a particular ROI. Most BRFs derived from lower-extremity joint kinematics and kinetics were located in the frontal and transverse planes of motion. Further, plantar pressure, vertical ground reaction force loading rate and free moment-related parameters were identified as kinetic BRFs.

CONCLUSION

This study offers a comprehensive overview of BRFs for the most common ROIs, which might serve as a starting point to develop ROI-specific risk profiles of individual runners. We identified limited evidence for most ROI-specific risk factors, highlighting the need for performing further high-quality studies in the future. However, consensus on data collection standards (including the quantification of workload and stress tolerance variables and the reporting of injuries) is warranted.

Comparing Functional Motor Control Exercises With Therapeutic Exercise in Wrestlers With Iliotibial Band Syndrome

Context: Iliotibial band syndrome (ITBS) is a common overuse injury in runners with parallels to our findings of overuse in Greco Roman wrestlers. Despite research indicating coordination and movement-based factors about the hip, no studies were found using functional motor control (FMC) in runners or wrestlers with ITBS. Thus, we compared FMC exercises and therapeutic exercises (TEs) on pain, function, muscle strength, and range of motion (ROM) in national-level Greco Roman wrestlers with ITBS. Design: Controlled laboratory study. Methods: Sixty national-level Greco Roman wrestlers diagnosed with ITBS were randomly assigned to 8 weeks of FMC exercises, TE, and a control group (20 individuals for each group). Pain (visual analog scale), function (triple hop test for distance, single-leg vertical jump test, and agility T test), muscle strength (handheld dynamometer), and ROM (goniometer) were measured at baseline and 8 weeks after intervention as posttest. Results: Although both interventions significantly reduced pain (P < .001, η2 = .87), improved function (triple hop test P = .004, η2 = .94; single-leg vertical jump P = .002, η2 = .93; and T test P < .001, η2 = .93) and strength (hip abduction (P < .001, η2 = .52), hip external rotation (P = .02, η2 = .95), knee flexion (P ≤ .001, η2 = .94), and knee extension (P < .001, η2 = .91) compared with the control group, FMC showed more significant improvements in comparison with TE. Significant differences (P = .001) were observed between FMC and TE compared with the control group in ROM outcome. However, TE was more effective than FMC in improving ROM hip abduction (P < .001, η2 = .93), hip adduction (P = .000, η2 = .92), hip internal rotation (P < .001, η2 = .92), and hip external rotation (P < .001, η2 = .93). Conclusion: FMC exercises were superior to TE in terms of pain, function, and muscle strength, whereas TE was more effective for improving ROM. FMC exercise is suggested as an effective intervention for improvement of the outcomes related to ITBS in national-level Greco Roman wrestlers.

Bilateral differences in coordination variability among injured and uninjured runners: A prospective study

This prospective cohort study aimed to identify bilateral differences in coordination variability (CAV) to determine if limb-specific CAV or CAV asymmetry is associated with running-related overuse injury (RRI) development in recreational runners. Lower limb kinematics were collected at enrollment. Runners were classified as injured (n = 14) or controls (n = 17) based on RRI incidence during a ≥ 6-month follow-up. Pelvis-thigh, knee-shank, knee-ankle, and shank-ankle CAV was quantified bilaterally within thirds of stance using modified vector coding. Wilcoxon Signed-Rank tests compared CAV between limbs within each group, and Wilcoxon Rank-Sum tests compared CAV asymmetry between groups (α ≤ 0.05). Injured runners displayed elevated injured versus uninjured limb CAV during initial-stance for all couplings (p < 0.010,d(effect size) = 0.51-1.31) except pelvis-thigh (p = 0.060,d = 0.36). During mid-stance, the injured limb exhibited restricted knee-ankle CAV (p < 0.010,d = 0.413) and elevated pelvis-thigh CAV (p < 0.010,d = 0.23). Controls also displayed bilateral differences specifically in pelvis-thigh CAV across stance, shank-ankle CAV during initial-stance, in all couplings during mid-stance, and shank-ankle CAV during late-stance (p < 0.010-0.025,d = 0.09-0.63). Comparing CAV asymmetry between groups revealed lower asymmetry among injured runners compared with controls for knee-ankle coupling in mid-stance and all couplings except pelvis-thigh during late-stance (p < 0.010,d = 0.85-1.87). Injured runners also displayed greater knee-shank CAV asymmetry in mid-stance versus controls (p < 0.010,d = 0.85). Logistic regression (α ≤ 0.05) revealed that between-limb CAV asymmetry did not predict RRI (p = 0.161), however, the odds of RRI were > 20% in the limb with either elevated shank-ankle CAV in initial-stance (p = 0.020) or elevated knee-ankle CAV in mid-stance (p = 0.043) than the contralateral limb. Therefore, limb-specific CAV rather than degree of CAV asymmetry may influence risk of RRI.

Conservative treatment of iliotibial band syndrome in runners: Are we targeting the right goals?

OBJECTIVE

Iliotibial band syndrome (ITBS) is presumably caused by excessive tension in the iliotibial band (ITB) leading to compression and inflammation of tissues lying beneath it. Usually managed conservatively, there is a lack of scientific evidence supporting the treatment recommendations, and high symptom recurrence rates cast doubt on their causal effectiveness. This review discusses the influence of common physiotherapeutic measures on risk factors contributing to tissue compression beneath the ITB.

METHODS

The potential pathogenic factors are presented on the basis of a simple biomechanical model showing the forces acting on the lateral aspect of the knee. Existent literature on the most commonly prescribed physiotherapeutic interventions is critically discussed against the background of this model. Practical recommendations for the optimization of physiotherapy are derived.

RESULTS

According to biomechanical considerations, ITBS may be promoted by anatomical predisposition, joint malalignments, aberrant activation of inserting muscles as well as excessive ITB stiffness. Hip abductor strengthening may correct excessive hip adduction but also increase ITB strain. Intermittent stretching interventions are unlikely to change the ITB's length or mechanical properties. Running retraining is a promising yet understudied intervention.

CONCLUSIONS

High-quality research directly testing different physiotherapeutic treatment approaches in randomized controlled trials is needed.

Increasing Step Rate Affects Rearfoot Kinematics and Ground Reaction Forces during Running

Simple Summary

Excessive movements, or inadequate timing in movement patterns, during running may contribute to the development of some running-related injuries. Specifically, excessive movement at the rearfoot, influencing lower leg rotation, has been a focus on different running-related injuries. One method to change how the lower limbs move is to increase step rate, or cadence. There is little research available describing how the rearfoot is affected by changes in step rate; therefore, the primary purpose of this study was to evaluate the effects of increasing step rate on rearfoot motion during running. Reflective markers were placed on twenty runners’ lower legs and feet in order to capture leg and foot movements while running on a treadmill at the runners’ preferred speed and step rate. Step rate was increased by 5% and 10%, while runners were cued by a metronome. Three-dimensional rearfoot motion was calculated during the stance phase (foot in contact with the ground) of running. The main finding of this study was that increasing step rate decreased peak rearfoot and lower leg rotation. These findings may be useful for rehabilitation for some running-related injuries.

Abstract

Relatively high frontal and transverse plane motion in the lower limbs during running have been thought to play a role in the development of some running-related injuries (RRIs). Increasing step rate has been shown to significantly alter lower limb kinematics and kinetics during running. The purpose of this study was to evaluate the effects of increasing step rate on rearfoot kinematics, and to confirm how ground reaction forces (GRFs) are adjusted with increased step rate. Twenty runners ran on a force instrumented treadmill while marker position data were collected under three conditions. Participants ran at their preferred pace and step rate, then +5% and +10% of their preferred step rate while being cued by a metronome for three minutes each. Sagittal and frontal plane angles for the rearfoot segment, tibial rotation, and GRFs were calculated during the stance phase of running. Significant decreases were observed in sagittal and frontal plane rearfoot angles, tibial rotation, vertical GRF, and anteroposterior GRF with increased step rate compared with the preferred step rate. Increasing step rate significantly decreased peak sagittal and frontal plane rearfoot and tibial rotation angles. These findings may have implications for some RRIs and gait retraining.

Clinical Indoor Running Gait Analysis May Not Approximate Outdoor Running Gait Based on Novel Drone Technology

BACKGROUND

Traditional running gait analysis is limited to artificial environments, but whether treadmill running approximates overground running is debated. This study aimed to compare treadmill gait analysis using fixed video with outdoor gait analysis using drone video capture.

HYPOTHESIS

Measured kinematics would be similar between natural outdoor running and traditional treadmill gait analysis.

STUDY DESIGN

Crossover study.

LEVEL OF EVIDENCE

Level 2.

METHODS

The study population included cross-country, track and field, and recreational athletes with current running mileage of at least 15 km per week. Participants completed segments in indoor and outdoor environments. Indoor running was completed on a treadmill with static video capture, and outdoor segments were obtained via drone on an outdoor track. Three reviewers independently performed clinical gait analysis on footage for 32 runners using kinematic measurements with published acceptable intra- and interrater reliability.

RESULTS

Of the 8 kinematic variables measured, 2 were found to have moderate agreement indoor versus outdoor, while 6 had fair to poor agreement. Foot strike at initial contact and rearfoot position at midstance had moderate agreement indoor versus outdoor, with a kappa of 0.54 and 0.49, respectively. The remaining variables: tibial inclination at initial contact, knee flexion angle initial contact, forward trunk lean full gait cycle, knee center position midstance, knee separation midstance, and lateral pelvic drop at midstance were found to have fair to poor agreement, ranging from 0.21 to 0.36.

CONCLUSION

This study suggests that kinematics may differ between natural outdoor running and traditional treadmill gait analysis.

CLINICAL RELEVANCE

Providing recommendations for altering gait based on treadmill gait analysis may prove to be harmful if treadmill analysis does not approximate natural running environments. Drone technology could provide advancement in clinical running recommendations by capturing runners in natural environments.

The Use of a Single Trunk-Mounted Accelerometer to Detect Changes in Center of Mass Motion Linked to Lower-Leg Overuse Injuries: A Prospective Study

Movement dynamics during running was previously characterized using a trunk-mounted accelerometer, and were associated with a history of overuse injuries. However, it remains unknown if these measures are also linked to the development of overuse injuries. The aim of this study was therefore to determine how movement dynamics alter in response to fatigue, and the possible link with developing lower-leg overuse injuries during a six-month follow-up period. Two hundred and eight movement science university students completed a 12-min all-out run while wearing a trunk-mounted accelerometer. Dynamic stability, dynamic loading and spatiotemporal measures were extracted from the accelerometer. Participants sustaining an injury within the 6-month period demonstrated significantly higher RMS ratio values in the vertical direction and lower RMS ratio values in the anteroposterior direction, and lower impact acceleration values in the anteroposterior direction in an unfatigued state compared to the uninjured group. They also demonstrated an increase in dynamic loading in the horizontal plane during the run. In addition, with running fatigue both groups exhibited changes in dynamic stability and loading measures. These results show the potential of using a single trunk-mounted accelerometer to detect changes in movement dynamics that are linked to lower-leg overuse injuries.

The influence of maturation and sex on pelvis and hip kinematics in youth distance runners

OBJECTIVES

This study aimed to investigate differences in stance phase pelvic and hip running kinematics based on maturation and sex among healthy youth distance runners.

DESIGN

Cross-Sectional.

METHODS

133 uninjured youth distance runners (M = 60, F = 73; age = 13.5 ± 2.7 years) underwent a three-dimensional running analysis on a treadmill at a self-selected speed (2.8 ± 0.6 m·s^-1). Participants were stratified as pre-pubertal, mid-pubertal, or post-pubertal according to the modified Pubertal Maturational Observation Scale. Stance phase pelvis and hip range of motion (RoM) and peak joint positions were extracted. Two-way ANCOVAs (sex, maturation; covariate of running velocity) were used with Bonferroni-Holm method to control for multiple comparisons with a target alpha level of 0.05.

RESULTS

A two-way interaction between sex and maturation was detected (p = 0.009) for frontal plane pelvic obliquity RoM. Post-hoc analysis identified a maturation main effect only among females (p˂0.008). Pelvic obliquity RoM was significantly greater among post-pubertal (p = 0.001) compared to pre-pubertal females. Significant main effects of sex (p = 0.02), and maturation (p = 0.01) were found for hip adduction RoM. Post-hoc analysis indicated a significant increase in hip adduction RoM from pre-pubertal to post-pubertal female runners (p = 0.001). A significant main effect of sex was found for peak hip adduction angle (p = 0.001) with female runners exhibiting greater maximum peak hip adduction compared to males.

CONCLUSIONS

Maturation influences pelvic and hip kinematics greater in female than male runners. Sex differences became more pronounced during later stages of puberty. These differences may correspond to an increased risk for running-related injuries in female runners compared to male runners.

Mechanics, energetics and implementation of grounded running technique: a narrative review

Grounded running predominantly differs from traditional aerial running by having alternating single and double stance with no flight phase. Approximately, 16% of runners in an open marathon and 33% of recreational runners in a 5 km running event adopted a grounded running technique. Grounded running typically occurs at a speed range of 2–3 m·s⁻¹, is characterised by a larger duty factor, reduced vertical leg stiffness, lower vertical oscillation of the centre of mass (COM) and greater impact attenuation than aerial running. Grounded running typically induces an acute increase in metabolic cost, likely due to the larger duty factor. The increased duty factor may translate to a more stable locomotion. The reduced vertical oscillation of COM, attenuated impact shock, and potential for improved postural stability may make grounded running a preferred form of physical exercise in people new to running or with low loading capacities (eg, novice overweight/obese, elderly runners, rehabilitating athletes). Grounded running as a less impactful, but metabolically more challenging form, could benefit these runners to optimise their cardio-metabolic health, while at the same time minimise running-related injury risk. This review discusses the mechanical demands and energetics of grounded running along with recommendations and suggestions to implement this technique in practice.

Current Clinical Concepts: Synthesizing the Available Evidence for Improved Clinical Outcomes in Iliotibial Band Impingement Syndrome

The current paradigm of insidious lateral knee pain involving the iliotibial band (ITB) in repetitive knee-flexion activities has been termed ITB friction syndrome since 1975. The original model for ITB pain was based on a limited or incorrect understanding of the relevant anatomy, biomechanics, and tissue science, which gradually led to a plethora of frustrating and ineffective interventional strategies. Mounting evidence from arthroscopic, cadaveric, and biomechanical studies, as well as from diagnostic imaging and histologic reports, has helped deconstruct this long-held paradigm for ITB-related pathology and treatment. By outlining the historical paradigm for our understanding of ITB pain and gathering newer evidence through extensive research, I will synthesize the available data in this clinical update to present an updated, more informed model for understanding insidious-onset ITB-related pathology and treating patients. The result is called ITB impingement syndrome.

Sex-Specific Hip Movement Is Correlated With Pelvis and Upper Body Rotation During Running

There is a sex bias for common overuse running injuries that are associated with sex-specific hip kinematics. Gait retraining programs aimed at altering hip kinematics may be more efficient if they incorporated an understanding of how hip kinematics are correlated with the movement of the remaining body segments. We applied a principal component analysis to structure the whole-body running kinematics of 23 runners (12 ♀) into k = 12 principal movements (PM_k), describing correlated patterns of upper and lower body movements. We compared the time-dependent movement amplitudes with respect to each PM_k between males and females using a waveform analysis and interpreted our findings according to stick figure animations. The movement amplitudes of two PMs (PM₆ and PM₈) showed statistically significant effects of "sex," which were independent of running speed. According to PM₈, females showed more hip adduction, which correlated with increased transverse rotation of the pelvis and upper body compared to men. We propose that increased hip adduction and upper body rotation in female runners may be a strategy to compensate for a less efficient arm and upper body swing compared to men. Gait interventions aimed at reducing hip adduction and running-related injuries in female runners should consider instructions for both upper and lower body to maximize training efficacy.

Patellar mobility and lower limb kinematics during functional activities in individuals with and without patellar tendinopathy

STUDY DESIGN

Case-control.

OBJECTIVE

To examine whether patients with patellar tendinopathy (PT) display greater patellar mobility and different lower body kinematics than patients without PT.

BACKGROUND

PT is a common overuse condition of the patellar tendon that can cause pain and impair function. Subjects with overuse knee problems display different hip and knee functional mechanics, specifically valgus collapse. Patellar hypermobility has not been specifically studied as a possible risk factor for PT.

METHODS

11 patients with PT and 11 controls without PT, age 18 to 40, were studied. Using a patellofemoral arthrometer (PFA), maximal lateral and medial patellar displacement was measured. 3-D motion analysis was performed to determine lower extremity joint motions during single-leg step down and drop vertical jump tests.

RESULTS

Patients with PT had significantly increased lateral patellar mobility compared to controls (12.21 ± 3.33 mm vs. 9.19 ± 1.92 mm, P = .017). PT patients showed significantly greater peak hip adduction with both drop vertical jump (2.7° ± 6.3° vs. -5.6° ± 4.2°; P = .003) and step down (17.0° ± 3.8° vs. 12.5° ± 4.4°, P = .024). PT patients demonstrated increased peak ankle external rotation with drop vertical jump (-21.1° ± 5.9° vs. -14.8° ± 5.5°, P = .023) and step down (-15.6° ± 5.5° vs. -9.0° ± 6.0°, P = .017).

CONCLUSIONS

Patients with PT exhibit increased lateral patellar mobility, hip adduction, and ankle external rotation. The effects of increased patellar mobility deserve further study in the development, management, and prevention of PT.

Comparison of Frontal and Transverse Plane Kinematics Related to Knee Injury in Novice Versus Experienced Female Runners

Novice runners experience a higher incidence of knee injury than experienced runners, which may be related to aberrant frontal and transverse plane kinematics. However, differences in kinematics between novice and experienced runners have not been fully explored. For this study, 10 novice and 10 experienced female runners ran on a treadmill at 2.68 m/s. Ankle, knee, and hip joint angles during the stance phase were measured using a 3-dimensional motion capture system and modeled using cubic splines. Spline models were compared between groups using a generalized linear model (α = .05). Ninety-five percent confidence intervals of the difference between joint angles throughout stance were constructed to identify specific periods of stance where groups differed in joint position. Angle-angle diagrams of ankle and hip position in the frontal and transverse planes were constructed to depict joint coordination. Novice runners displayed less hip adduction, but greater knee abduction and knee internal rotation compared to experienced runners. Differences in knee joint position may be explained by coordination of hip and ankle motion. Greater knee abduction and knee internal rotation displayed by novice runners compared with experienced runners may help to explain their higher risk for injury.

Do Novice Runners Show Greater Changes in Biomechanical Parameters?

Purpose

Examining and understanding the biomechanics of novice runners and experienced runners can further improve our knowledge within the field of running mechanics and running injuries. The purpose of this study was to classify the differences in lower limb biomechanics during a 3.3 m/s running task among both experienced runners and novice runners.

Method

Twenty-four participants (12 experienced runners and 12 novice runners) ran at 3.3 m/s across a force plate; kinematics and kinetics data were collected by the Vicon motion system and Kistler force plate. Group comparisons were made using an independent samples t-test to identify differences in the impact peak, loading rate, contact time, ankle, knee, and hip joint kinematics and kinetics during the stance phase.

Results

No significant differences were observed between novice and experienced runners for both ankle and knee joint kinetics except that the ankle joint plantar flexion torque was significantly greater in the novice runners. However, the plantar flexion, dorsiflexion, range of motion (ROM), plantar flexion torque, and max angular velocity of ankle joint significantly increased in novice runners than inexperienced runners. Additionally, the flexion angle and range of motion of the hip joint were observed to be larger in the novice runners. Moreover, the maximum extension torque and the maximum extension power in the hip joint were significantly increased in the experienced runners. There were no significant differences in the first peak, contact time, and average vertical loading rate. Novice runners showed a larger vertical instantaneous loading rate than experienced runners.

Conclusion

These preliminary findings indicate that novice runners are prone to running injuries in comparison to experienced runners. Novice runners showed larger kinematics and kinetic parameters in the joint of the ankle and hip. Novice runners should enhance muscle strength in the hip and choose scientific training methods.

Performance on the Single-Legged Step Down and Running Mechanics

CONTEXT

Previous authors have shown associations between kinematics on the single-legged step down (SLSD) and running mechanics. Therefore, the SLSD may be a useful tool for identifying runners with poor running mechanics when 2- or 3-dimensional gait analysis is not available. However, the associations between SLSD performance and running kinetics, as well as the influences of sex and muscle strength on these relationships, remain unclear.

OBJECTIVE

To evaluate whether kinematics on the SLSD predict kinematics and kinetics while running and whether the relationships differ between men and women and are mediated by muscle strength.

DESIGN

Cross-sectional study.

SETTING

Biomechanics research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Fifty highly trained runners (25 men, 25 women; age = 27.8 ± 9.2 years, height = 1.69 ± 0.26 m, mass = 66.3 ± 15.0 kg, running distance = 45.2 ± 19.1 mile/wk [72.32 ± 30.56 km/wk]).

MAIN OUTCOME MEASURE(S)

Relationships between kinematics on the SLSD and kinematics and kinetics during running were evaluated. We also assessed whether muscle strength moderated these relationships.

RESULTS

For men, linear regression revealed that peak hip adduction (R2 = 0.306, P = .012), internal rotation (R2 = 0.439, P = .002), knee valgus (R2 = 0.544, P = .001), and rearfoot eversion (R2 = 0.274, P = .008) on the SLSD were strongly predictive of kinematics during running. In women, only peak hip internal rotation (R2 = 0.573, P = .001), knee valgus (R2 = 0.442, P = .001), and rearfoot eversion (R2 = 0.384, P = .012) predicted running kinematics. In women, total medial collapse on the SLSD predicted peak hip-adductor moment (R2 = 0.364, P = .001) during running. None of the relationships were moderated by muscle strength in either men or women.

CONCLUSIONS

Kinematics during the SLSD predicted kinematics while running in both men and women but only predicted kinetics while running in women. Given that none of the relationships between SLSD performance and running mechanics were moderated by muscle strength, clinicians should assess movement quality and strength independently.

Fatigue-Induced Hip-Abductor Weakness and Changes in Biomechanical Risk Factors for Running-Related Injuries

CONTEXT

Despite overlap between hip-abductor (HABD) weakness and fatigue-induced changes in running, the interaction of these theorized contributors to running injuries has been underevaluated.

OBJECTIVE

To assess the effects of a fatiguing run on HABD torque and evaluate the correlation between HABD torque and previously identified running-related injury pathomechanics while participants were rested or fatigued.

DESIGN

Crossover study.

SETTING

Laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 38 healthy, physically active males (age = 21.61 ± 4.02 years, height = 1.78 ± 0.08 m, body mass = 76.00 ± 12.39 kg).

INTERVENTION(S)

Data collection consisted of rested-state collection, a fatiguing treadmill-run protocol, and fatigued-state collection. For the HABD measures, side-lying handheld-dynamometer isometric tests were performed and converted to torque using femur length. For the gait analysis, kinematic (240 Hz) and kinetic (960 Hz) running (4.0 m/s) data were collected for 3 trials. The fatigue protocol involved a graded exercise test and 80% o2max run to exhaustion. Immediately after the run, fatigued-state measures were obtained.

MAIN OUTCOME MEASURE(S)

Variables of interest were HABD torque and peak angles, velocities, and moments for hip and knee adduction and internal rotation. Differences between conditions were compared using paired t tests. Pearson correlation coefficients were calculated to evaluate relationships between HABD torque and biomechanical variables.

RESULTS

Fatigue decreased HABD torque and increased hip-adduction angle, knee-adduction velocity, and hip and knee internal-rotation velocities and moments (all P values < .05). In the rested state, HABD torque was correlated with hip-adduction velocity (r = -0.322, P = .049). In the fatigued state, HABD torque was correlated with hip-adduction velocity (r = -0.393, P = .015), hip internal-rotation velocity (r = -0.410, P = .01), and knee-adduction angle (r = 0.385, P = .017) and velocity (r = -0.378, P = .019).

CONCLUSIONS

Changes in joint velocities due to fatigue and correlations between HABD torque and hip- and knee-joint velocities highlight the need to consider not only the quantity of HABD strength but also the rate of eccentric control of HABDs.

VALIDITY AND RELIABILITY OF VIDEO-BASED ANALYSIS OF UPPER TRUNK ROTATION DURING RUNNING

Background

Two-dimensional (2D) video analysis is a practical tool for assessing biomechanical factors that may contribute to running-related injury. Asymmetrical or altered coordination of transverse plane trunk movement has been associated with low back pain, increased vertical and horizontal ground reaction forces, and altered hip abduction torque and strength. However, the reliability and validity of 2D transverse plane upper trunk rotation (UTR) has not been assessed.

Study Design

Validity and reliability study.

Purpose

To determine the validity and reliability of 2D video-based, transverse plane UTR measurement during running.

Methods

Sixteen runners ran at self-selected speed on a treadmill while three-dimensional (3D) and 2D motion capture occurred synchronously. Two raters measured peak UTR for five consecutive strides on two occasions. Interrater and intrarater reliability and the minimum detectable change was calculated for right and left peak 2D UTR measurement. Concurrent validity and agreement between 2D and 3D measures were determined by calculating Pearson Product Correlation Coefficients (r) and Bland-Altman plots, respectively.

Results

Using a single UTR measure per runner, intrarater and interrater reliability (ICC_2,1) was excellent (intrarater ICC_2,1 range: 0.989-0.999; interrater ICC_2,1 range: 0.990-0.995) and the minimum detectable change was 0.39-1.4 degrees. Measurements in 2D and 3D were significantly correlated for peak UTR (all r ≥ 0.986; all p-values < 0.001) and showed good agreement in Bland-Altman plots.

Conclusion

Two-dimensional video-based measurement of transverse plane peak UTR is valid and reliable.

Clinical Relevance

UTR measurement may provide clinical insight into gait deviations in the transverse plane that alter angular momentum and increase risk for running-related injury.

Level of Evidence

2B.

Instructed versus spontaneous entrainment of running cadence to music tempo

Matching exercise behavior to musical beats has been shown to favorably affect repetitive endurance tasks. In this study, our aim was to explore the role of spontaneous versus instructed entrainment, focusing on self‐paced exercise of healthy, recreational runners. For three 4‐min running tasks, 33 recreational participants were either running in silence or with music; when running with music, either no instructions were given to entrain to the music, or participants were instructed to match their running cadence with the tempo of the music. The results indicated that less entrainment occurred when no instruction to match the exercise with the musical tempo was provided. In addition, similar to the condition without music, lower speeds and shorter step lengths were observed when runners were instructed to match their running behavior to the musical tempo when compared with the condition without such instruction. Our findings demonstrate the impact of instruction on running performance and stress the importance of intention to entrain running behavior to musical beats.

Effects of a band loop on muscle activity and dynamic Knee valgus during pedaling

BACKGROUND

Change in the lower extremity alignments in the frontal plane and muscle activation patterns have been associated with lower extremity injuries. Therefore, to prevent injuries, many therapeutic protocols focus on find ways to correct dynamic knee valgus (DKV).

METHODS

Thirty-one recreational male cyclists with DKV (26.4 ± 4.5 years, 176.63 ± 7.51 cm, 75.81 ± 9.29 kg, 23.20 ± 4.15 kg/m2) volunteered to participate in this study. Simultaneous recordings of kinematic and electromyography data were performed on ten consecutive pedal cycles which began during the last 30 seconds of each four test condition: with band at 0.5 kg workload, with band at 2 kg workload, without band at 0.5 kg workload, and without band at 2 kg workload. The paired t-test was used for statistical analysis (p < 0.05).

RESULTS

The results indicated significant differences in VM (band = 0.029, no band = 0.031) and VL (band = 0.015, no band = 0.035) activation between workloads in each condition. Also there were significant differences in Gmed activation (0.5kg = 0.001, 2kg = 0.037), onset of Gmed (0.5kg = 0.048, 2kg = 0.012), offset of Gmed (0.5kg = 0.048, 2kg = 0.015), TFL activation (0.5kg = 0.001, 2kg = 0.041) and offset of TFL (0.5kg = 0.078, 2kg = 0.005) between the band and no band conditions. There was no different significant in VM/VL ratio between in each of four testing conditions (p > 0.05). The Gmed/TFL ratio was significantly greater in band condition than no band at both 0.5 (p = 0.045) and 2 kg (p = 0.001) workload. Knee abduction angle was affected by the band loop during the pedaling at two different workloads (0.5 kg: p = 0.047, 2 kg: p = 0.021) but mean (p = 0.027) and peak (p = 0.033) knee abduction angle significantly increased with increasing workload during the pedaling with band loop.

CONCLUSIONS

pedaling with the band loop can be considered as an effective method to increase the Gmed, Gmed/TFL ratio and control of DKV but increasing the workload during pedaling must be done with caution to prevent DKV.

Impact-Related Ground Reaction Forces Are More Strongly Associated With Some Running Injuries Than Others

BACKGROUND

Inconsistent associations have been reported for impact-related ground reaction force variables and running injuries when grouping all injuries together. However, previous work has shown more consistent associations when focusing on specific injuries.

PURPOSE

To compare ground reaction force variables between healthy and injured runners as a group and within specific common injuries.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 125 runners presenting with patellofemoral pain, tibial bone stress injury, plantar fasciitis, Achilles tendinopathy, or iliotibial band syndrome and 65 healthy controls completed an instrumented treadmill assessment at a self-selected speed. Impact-related ground reaction force variables included vertical average (VALR) and instantaneous (VILR) load rates, posterior and medial/lateral instantaneous load rates, and vertical stiffness at initial loading (VSIL). Mean comparisons were made between the general and specific injury and control groups (α = .05). Cutoff thresholds were established and evaluated using several criteria.

RESULTS

VALR (+17.5%; P < .01), VILR (+15.8%; P < .01), and VSIL (+19.7%; P < .01) were significantly higher in the overall injured versus control groups. For individual injuries, VALR, VILR, and VSIL were significantly higher for patellofemoral pain (+23.4%-26.4%; P < .01) and plantar fasciitis (+17.5%-29.0%; P < .01), as well as VSIL for Achilles tendinopathy (+29.4%; P < .01). Cutoff thresholds showed better diagnostic criteria for individual versus grouped injuries.

CONCLUSION

Impact variables (VALR, VILR, and VSIL) were significantly higher when assessing the injured group as a whole. However, these findings were driven by specific injury groups, highlighting the importance of taking an injury-specific approach to biomechanical risk factors for running injury.

CLINICAL RELEVANCE

These results suggest that practitioners may want to address impact loading in their treatment of injured runners, especially in those with patellofemoral pain and plantar fasciitis.