Potential neurophysiological and biomechanical risk factors for sport-related back problems: A scoping review

This scoping review aims (1) to map the literature dealing with neurophysiological and biomechanical aspects of back problems in athletes in order to identify valid risk-factors for their prevention, plus (2) to identify gaps in the existing research and propose suggestions for future studies. A literature search conducted with Scopus, Web of Science, MEDLINE and Cochrane Library was completed by Elsevier, SpringerLink and Google Scholar. The main neurophysiological risk factors identified leading to back problems in athletes are neuromuscular imbalance, increased muscle fatigability, muscle dysfunction and impaired motor control, whilst biomechanical risk factors include maladaptive spinal, spinopelvic and lower limb kinematics, side-to-side imbalances in axial strength and hip rotation range of motion, spinal overloading and deficits in movement pattern. However, most studies focused on back pain in the lumbar region, whereas less attention has been paid to thoracic and cervical spine problems. The range of sports where this topic has been studied is relatively small. There is a lack of research in sports in which the core muscles are highly involved in specific movements such as lifting weights or trunk rotations. A limited number of studies include female athletes and master athletes of both genders. In addition to chronic back pain patients, it is equally important to conduct research on healthy athletes with a predisposition to spine problems. Investigators should focus their empirical work on identifying modifiable risk factors, predict which athletes are at risk for back problems, and develop personalized sport-specific assessment tools and targeted prevention strategies for them. This review was registered using the Open Science Framework Registries (https://osf.io/ha5n7).

The effect of lower back and lower-extremity kinesiology taping on static balance and physical function performance in people with multiple sclerosis: A pilot study

INTRODUCTION

Multiple sclerosis (MS) can lead to numerous deficits in body functions, including balance and mobility impairment. This study examined the effect of lower back and lower extremity kinesiology tape (KT) application on static balance and physical functioning performance in people with MS (pwMS) and compared that to a non-elastic tape.

METHODS

This pilot randomized study recruited and enrolled 10 participants with MS that were allocated into two groups: kinesio (n = 6) and non-elastic (n = 4) tape. Participants were assessed with and without the respective tape on static balance with eyes open and closed and various physical function tests.

RESULTS

Effect sizes for the Kinesio tape intervention were found to be small, while effect sizes for the sham tape/place condition varied from small to high. For both groups, the tendency was to reduce or maintain performance on the tests comparing tape and no tape. A subsequent, mixed-factor ANOVA revealed no significant difference between KT or sham tape/placebo.

CONCLUSION

Our findings suggest that KT applied on lower back and lower extremity muscles does not seem to improve static balance and physical function performance in pwMS.

False-Positive Rates, Risk Factors, and Interpretations of the Vestibular Ocular Motor Screen in Collegiate Athletes

CONTEXT

Biological sex and history of motion sickness are known modifiers associated with a false-positive baseline Vestibular Ocular Motor Screen (VOMS). However, other factors may associate with a false-positive VOMS in collegiate athletes.

OBJECTIVE

Identify contributing factors to false-positive VOMS assessments using population specific criteria. We also critically appraised previously reported interpretation criterion.

DESIGN

Descriptive Laboratory.

SETTING

Single site collegiate athletic training clinic.

PATIENTS OR OTHER PARTICIPANTS

NCAA Division 1 athletes (n=462[41% female]) who were 18.8±1.4 years old.

MAIN OUTCOME MEASURES

Participants completed the Athlete Sleep Behavior Questionnaire (ASBQ), Generalized Anxiety Index (GAD-7), the ImPACT battery, Patient Health Questionnaire (PHQ-9), Revised Head Injury Scale (HIS-r), the Sensory Organization Test (SOT), and the VOMS as part of a multidimensional baseline concussion assessment. Participants were classified into two groups based on whether they had a total symptom score of ≥8 following VOMS administration, excluding the baseline checklist. Chi-squared (χ2) and independent t-tests compared group demographics. A binary logistic regression with adjusted odds ratios (OR) evaluated the influence of sex, corrected vision, ADHD, ImPACT composite scores, concussion history, a history of treatment for headache and/or migraine, GAD-7, PHQ-9, ASBQ, and SOT Equilibrium Score, and Somatosensory, Visual, and Vestibular sensory ratios on false-positive rates.

RESULTS

Approximately 9.1% (42/462 [30 females]) met criteria for a false-positive VOMS. A significantly greater proportion of females had false-positives (χ2(1) = 18.37, p < 0.001). Female sex (OR=2.79, 95% CI [1.17-6.65], p =.02) and history of treatment for headache (OR=4.99, 95% CI [1.21-20.59], p=0.026) were the only significant predictors of false-positive VOMS. Depending on cutoff interpretation, false-positive rates using our data ranged from 9.1%-22.5%.

CONCLUSIONS

Our results support the most recent interpretation guidelines for the VOMS in collegiate athletes due to a low false-positive rate and ease of interpretation. Biological sex and history of headaches should be considered when administering the VOMS in the absence of a baseline.

Low back pain in adolescent rowers: Association to muscle changes detected by magnetic resonance imaging

Adult elite rowers are at risk of developing low back pain (LBP). However, LBP data on adolescent elite rowers is currently insufficient. Therefore, the aim of this study was to assess LBP prevalence, LBP intensity and training characteristics in male adolescent elite rowers and a healthy control group. Twenty rowers (mean age 15.8 ± 1.2 years) and a non-athletic control group matched by age and gender (n = 13) were prospectively enrolled and underwent LBP assessment with a validated questionnaire and magnetic resonance imaging (MRI) of the lumbar spine muscles, which included a T2-mapping sequence. From the quantitative image data, T2 relaxation times were calculated. The prevalence of LBP in the last 24 hours and 3 months in the rowing group was 55.0% and 85.0%, respectively, compared to 23.1% and 30.8% in the control group (p < 0.001). Rowers had significantly longer T2 relaxation times of the paraspinal muscles compared to controls (p ≤ 0.041). LBP intensity was associated with longer T2 relaxation times (p < 0.001). Adolescent rowers had a higher prevalence of LBP compared to an age-matched control group. The observed increase in T2 relaxation might be explained by muscle soreness due to strenuous exercise, which is correlated with short-term pain intensity.

Ankle proprioception in table tennis players: Expertise and sport-specific dual task effects

OBJECTIVES

To compare ankle proprioception between professional adolescent table tennis players at national and regional levels and age-matched non-athletes, and, in a nominally upper-limb sport, to explore the relationships between single- and dual-task ankle proprioception, years of training and sport-specific performance.

DESIGN

Cross-sectional observational study.

METHODS

Fifty-five participants (29 professional adolescent table tennis players and 26 non-athletic peers) volunteered. Ankle proprioception was first assessed using the active movement extent discrimination apparatus (AMEDA-single) for all; yet only the players were then re-assessed while executing a secondary ball-hitting task (AMEDA-dual). The mean Area Under the Receiver Operating Characteristic Curve was calculated as the proprioceptive score, and years of training and hitting rate were recorded.

RESULTS

National-level players had significantly better ankle proprioception as shown by higher AMEDA-single scores than the other groups (all p < 0.05). Ankle proprioceptive performance was significantly impaired while ball-hitting (F1,28 = 58.89, p ≤ 0.001, ηp2 = 0.69). National-level players outperformed the regional-level significantly on the AMEDA-dual task (F1,27 = 21.4, p ≤ 0.001, ηp2 = 0.44). Further, ankle proprioceptive performance was related to expertise, in that both AMEDA-single and AMEDA-dual proprioceptive scores were correlated with years of training and ball-hitting rate (r from 0.40 to 0.54, all p < 0.05).

CONCLUSIONS

Ankle proprioception is a promising measure that may be used to identify different ability levels among adolescent table tennis players. Superior ankle proprioception may arise from rigorous training and contribute to stroke accuracy. Dual-task proprioceptive assessment suggests how elite table tennis players perform differently from lower-ranked players in complex and changeable sports circumstances.

The effects of different small-sided games configurations on heart rate, rating of perceived exertion, and running demands in professional soccer players

We examined the effects of different small-sided games (SSG) configurations on heart rate (HR), rating of perceived exertion (RPE), and running demands in soccer players. Twelve male soccer players (U18) participated in this randomized cross-over study. Players performed three SSG in different "fixed" and "dynamic" pitch sizes (3v3 in large (SSGL) and small (SSGS) fixed area; or 3v3 in dynamic dimensions [SSGD]), with 4x4 minutes interspersed by 2 minutes of rest. HR measures (maximum [HRmax], average [HRavg], and percentage of maximum [%HRmax]), RPE, and running demands were collected across the SGG sessions. The following running activities were recorded: total distance covered (TD), distance covered (DC) at 6-12 km·h-1, ≥ 12-18 km·h-1, and >18 km·h-1, peak running speed, acceleration (ACC) and deceleration (DEC) at 1-2 m·s-2 and 2-3 m·s-2, player load, and high metabolic load distance (HMLD). SSGL displayed higher HRavg, %HRmax, and RPE values than SSGS (p < 0.05). SSGL resulted in higher TD, DC at 6-12 km·h-1, ≥ 12-18 km·h-1, > 18 km·h-1, and higher peak speed than SSGS and SSGD (p < 0.05). Moreover, SSGD presented higher TD and DC at 6-12 km·h-1 and ≥ 12-18 km·h-1 than SSGS (p < 0.05). In contrast, SSGD and SSGS showed higher number of ACC and DEC at 1-2 m·s-2 than SSGL (p < 0.05). In conclusion, the pitch size and playing area of the SSG can be manipulated to promote desired physiological and physical demands in young soccer players.HighlightsWe examined how fixed (small and large) or variable (dynamic) pitch sizes affected the psychophysiological and running demands of young soccer players during small-sided games.Small-sided games with larger pitch sizes and areas per player elicited greater psychophysiological and running demands than small areas.The pitch size designed in the current study does not appear to affect the number of acceleration and deceleration (> 2 m·s-2).Varying the pitch size during the small-sided games (i.e. dynamic condition) could be an interesting constraint to be considered by soccer coaches in order to enhance task variability.

Databases for Researching Athletic Training Literature

Searching the athletic training literature can be confusing and overwhelming with many possible databases for locating relevant peer-reviewed scholarship. Finding evidence-based literature from respected publications is helpful in clinical decision-making for athletic training practitioners. This column details recommended databases and search tips to help students, staff, clinicians, and faculty in the field of athletic training find the literature they need to help make evidence-based decisions and to stay current with the published literature. Databases discussed include Cochrane, PubMed, SPORTDiscus, CINAHL, PEDro, Sports Medicine, and Education Index (formerly Physical Education Index), and Google Scholar.

Effects of Hyperbaric Oxygen Therapy on Mitochondrial Respiration and Physical Performance in Middle-Aged Athletes: A Blinded, Randomized Controlled Trial

Introduction

Hyperbaric oxygen therapy (HBOT) has been used to increase endurance performance but has yet to be evaluated in placebo-controlled clinical trials. The current study aimed to evaluate the effect of an intermittent HBOT protocol on maximal physical performance and mitochondrial function in middle-aged master athletes.

Methods

A double-blind, randomized, placebo-controlled study on 37 healthy middle-aged (40–50) master athletes was performed between 2018 and 2020. The subjects were exposed to 40 repeated sessions of either HBOT [two absolute atmospheres (ATA), breathing 100% oxygen for 1 h] or SHAM (1.02ATA, breathing air for 1 h).

Results

Out of 37 athletes, 16 HBOT and 15 SHAM allocated athletes were included in the final analysis. Following HBOT, there was a significant increase in the maximal oxygen consumption (VO2Max) (p = 0.010, effect size(es) = 0.989) and in the oxygen consumption measured at the anaerobic threshold (VO2AT)(es = 0.837) compared to the SHAM group. Following HBOT, there were significant increases in both maximal oxygen phosphorylation capacity (es = 1.085, p = 0.04), maximal uncoupled capacity (es = 0.956, p = 0.02) and mitochondrial mass marker MTG (p = 0.0002) compared to the SHAM sessions.

Conclusion

HBOT enhances physical performance in healthy middle-age master athletes, including VO2max, power and VO2AT. The mechanisms may be related to significant improvements in mitochondrial respiration and increased mitochondrial mass.

Trial Registration ClinicalTrials.gov Identifier: https://clinicaltrials.gov/ct2/show/NCT03524989 (May 15, 2018).

Medical Supervision of Illinois Public and Private High School Athletics

BACKGROUND

High-school sports participation in the United States has increased over the years with a corresponding increase in the number of injuries. Leading medical and sports organizations nationwide advocate for an increase in proper medical supervision of athletes.

OBJECTIVES

To analyze athletic medical coverage in Illinois high schools and compare differences between public and private Illinois high school.

METHODS

A survey addressing various components of sports medical coverage was distributed in 2018 to all 810 Illinois High School Association (IHSA) high schools to be completed electronically.

RESULTS

The response rate was 50% (407/810 schools). Of the responding schools, 14% were private high schools and 86% public high schools. An orthopedic surgeon, family doctor, pediatrician, or another type of physician were present on sidelines in 9.2% of private high schools and 8.5% of public high schools. Athletic trainers (ATs) were present on sidelines in 91% of private high schools and in 79% of public high schools. There was 68% of private high schools reporting coaches trained in CPR versus 85% in public high schools. Both private and public high schools had high rates of having written emergency action plans (89% vs 91%), AED on site (100% vs 99%), written concussion management protocols (96% vs 97%).

CONCLUSION

Our study found similar rates of high school medical coverage as compared to national studies, with some significant differences found between private and public high schools. Most Illinois high schools had high rates of having written EAPs, concussion management protocols and AEDs on site. Overall, an increase of medical supervision and emergency preparedness is needed, which should come in the form of increasing AT and physician presence alongside community and school engagement for improved implementation of coverage.

Regulation of sinus node pacemaking and atrioventricular node conduction by HCN channels in health and disease

The funny current, I_f, was first recorded in the heart 40 or more years ago by Dario DiFrancesco and others. Since then, we have learnt that I_f plays an important role in pacemaking in the sinus node, the innate pacemaker of the heart, and more recently evidence has accumulated to show that I_f may play an important role in action potential conduction through the atrioventricular (AV) node. Evidence has also accumulated to show that regulation of the transcription and translation of the underlying Hcn genes plays an important role in the regulation of sinus node pacemaking and AV node conduction under normal physiological conditions - in athletes, during the circadian rhythm, in pregnancy, and during postnatal development - as well as pathological states - ageing, heart failure, pulmonary hypertension, diabetes and atrial fibrillation. There may be yet more pathological conditions involving changes in the expression of the Hcn genes. Here, we review the role of I_f and the underlying HCN channels in physiological and pathological changes of the sinus and AV nodes and we begin to explore the signalling pathways (microRNAs, transcription factors, GIRK4, the autonomic nervous system and inflammation) involved in this regulation. This review is dedicated to Dario DiFrancesco on his retirement.

The effect of an Olympic distance triathlon on the respiratory muscle strength and endurance in triathletes

High-intensity exercise, marathons, and long distances triathlons have been shown to induce the fatigue of respiratory muscles (RMs). Never-theless, fatigue and the recovery period have not been studied in re-sponse of an Olympic distance triathlon (1.5-km swim, 40-km bike, 10-km run: short-distance triathlon). The aim of this study was to evaluate the RM fatigue induced by an Olympic distance triathlon. Nine male triath-letes (24±1.1 years) underwent spirometric testing and the assessment of RM performance. Respiratory function tests were conducted in sit-ting position. Spirometric parameters, maximal inspiratory and expirato-ry pressures, and RM endurance assessed by measuring the time limit were evaluated before (pre-T), after (post-T), and the day following the triathlon (post-T-24 hr). Residual volume increased: pre-T vs. post-T (P<0.002), maximal inspiratory pressure significantly decreased from 127.4±17.2 (pre-T) to 121.6±18.5 cmH₂O (post-T) (P<0.001) and returned to the pre-T value 24 hr after the race (125.0±18.6). RM endurance sig-nificantly decreased from 4:51±0:8 (pre-T) to 3:13±0:7 min (post-T, P< 0.001) and then remained decreased for 24 hr after the race from 4:51± 0:8 (pre-T) to 3:39±0:4 min 24 hr after (P<0.002). Both, strength and en-durance of inspiratory muscles decrease after Olympic distance triath-lon. Furthermore, the impaired of inspiratory muscle endurance 24 hr after the race suggested a slow recovery and persistence of inspiratory muscle fatigue.

Spiritual Care Perspective of College Student-Athletes

Spirituality in healthcare has been researched in multiple healthcare professions; however, very little research has been done in athletic training, and no studies have investigated the athletes' perception. The purpose of our online survey study was to determine the perceptions of college student-athletes on spiritual care. Our participants included 268 collegiate student-athletes from both faith-based and non-faith-based institutions. Respondents agree that spirituality may affect treatment progress, addressing spiritual concerns of the athlete could result in a more positive outcome, and certified athletic trainers should have some basic skills and knowledge to support the spiritual needs of the athlete.

Athlete Cardiovascular Concerns in the Training Room: What Do I Do If…?

Cardiac disease can present in the training room through three portals: the preparticipation history and physical may identify concerns, the athlete may present with symptoms, or screening modalities may demonstrate abnormal findings. Training-related cardiovascular remodeling can mimic real disease, therefore providers must be able to separate the two. Sports medicine providers must be knowledgeable in how these present and how to care for these concerns to ensure proper care and avoid unnecessary restrictions of athletes. This article discusses 10 common cardiac concerns that can arise in the training room.

Epidemiologic comparisons of soccer-related injuries presenting to emergency departments and reported within high school and collegiate settings

BACKGROUND

Few studies compare sports injury patterns in different settings. This study described the epidemiology of soccer injuries presenting to emergency departments (EDs) and compared injuries presenting to EDs to injuries presenting to collegiate and high school athletic trainers (ATs).

METHODS

Soccer-related injuries (product code 1267) in the National Electronic Injury Surveillance System (NEISS) that were sustained by individuals at least two years of age in 2004-2013 were included. High School Reporting Information Online (HS RIO) data for high school soccer injuries during the 2005/06-2013/14 academic years were compared to NEISS data for those aged 14-17 years in 2005-2013. National Collegiate Athletic Association Injury Surveillance Program (NCAA-ISP) data for collegiate soccer injuries during the 2009/10-2013/14 academic years were compared to NEISS data for those aged 18-22 years in 2009-2013. All datasets included weights to calculate national estimates. Injury proportion ratios (IPRs) with 95% confidence intervals (CIs) compared nationally estimated injury distributions between the HS RIO/NCAA-ISP and NEISS data subsets.

RESULTS

During the study period, 63,258 soccer-related injuries were captured by NEISS, which translates to an estimated 2,039,250 injuries seen at US EDs nationwide. Commonly injured body parts included the head/face (19.1%), ankle (17.6%), hand/wrist (15.3%), and knee (12.2%). Common diagnoses included sprains/strains (34.0%), fractures (22.2%), and contusions (17.7%). Compared to their respective age ranges in NEISS, sprains/strains comprised a larger proportion of injuries in HS RIO (48.3% vs. 33.7%; IPR = 1.38; 95% CI: 1.33, 1.42) and NCAA-ISP (51.3% vs. 37.0%; IPR = 1.39; 95% CI: 1.31, 1.46). In contrast, fractures comprised a smaller proportion of injuries in HS RIO than in NEISS (7.5% vs. 18.6%; IPR = 0.43; 95% CI: 0.39, 0.47) and NCAA-ISP (2.8% vs. 15.7%; IPR = 0.18; 95% CI: 0.14, 0.22).

CONCLUSIONS

ATs more commonly reported injuries that are easily diagnosed and treated (e.g., sprains/strains); EDs more commonly reported injuries with longer recovery times and rehabilitation (e.g., fractures). Although ED surveillance data can identify the most severe sports-related injuries, high school and college sports surveillance may better describe the breadth of sports-related injuries. Our findings may provide further support for school-based sports medicine professionals, but further research is needed to comprehensively examine the potential economic and health-related benefits.

College Students' Knowledge of Recovery Beverage Serving Sizes

Previous research suggests that chocolate milk may be a beneficial recovery beverage, yet little is known about how athletes and students training for careers in sports science or health-related fields interpret recommended recovery beverage serving sizes. This study examined college students' ability to correctly apply serving size recommendations for chocolate milk and protein powder used during post-exercise recovery and assessed usual consumption of milk as a recovery beverage. College students (34 women, 39 men) poured the amount of chocolate milk they would consume within 90 minutes after exercise unaided and with the use of a serving size guide. They scooped the amount of protein powder they would use after exercising. Participants reported consuming about 1.3±1.8 glasses of milk and drinking a recovery beverage besides milk an average of 0.95±1.3 times in the past three days. The majority poured less than recommended. Student athletes poured significantly closer to the recommendation than non-athletes (436±128 ml versus 418±127 ml, p=0.016) and poured significantly closer to the recommendation after reviewing a serving size guide (p=0.038). Athletes and men served themselves significantly more protein powder than non-athletes (13.0±5.6 g versus 10.3±5.2 g, p=0.047) and women (12.5±6.0 g versus 9.8±4.4 g, p=0.041). Most participants reported that the serving size guide was easy to read and helpful. Nutrition education specific to post-exercise recovery beverages may help students improve accuracy when interpreting serving size recommendations.

Using a real-life case scenario to integrate additional health professions students into an existing interprofessional team seminar

The World Health Organization stated that the goal of interprofessional education (IPE) is to prepare students as collaboration-ready members of interprofessional care teams. Educators try to create meaningful and relevant learning experiences for multiple health professions students. A longitudinal Interprofessional Team Seminar (IPTS) course includes over 650 students from seven health professions at the professional training level. Recommendations from the National Athletic Trainers' Association (NATA) promote the inclusion of athletic training (AT) students in IPE initiatives. A new IPTS module included AT students focusing on the attributes of rapidly forming and different care teams as the patient transitions from an on-field injury, to acute care, inpatient care, and rehabilitative care, and back to activities of daily living. Qualitative review of reflections from the students assessed the impact of these IPTS modules. The intentional design of this course, focusing on behaviours of collaborative practice and supporting students to be collaboration ready, effectively introduced and highlighted profession-specific strengths and unique contributions to team-based care.

Does small-sided-games' court area influence metabolic, perceptual, and physical performance parameters of young elite basketball players?

The purpose of this study was to investigate the effect of court size on physiological responses and physical performance of young elite basketball players. Twelve male basketball players (18.6 ± 0.5 years; 88.8 ± 14.5 kg; 192.6 ± 6.5 cm) from an under-19 team performed two small-sided games (matches) with different court areas (28x15 m and 28x9 m; 28x15 and 28x9 protocols). The number of players (3x3) was kept the same in each protocol. The players performed a repeated-sprint ability (RSA) test before and after each match. Blood lactate concentration was collected before (pre) and after (post) the matches, and the session rating of perceived exertion (session-RPE) was determined 30 minutes after the match. Best and mean time in the RSA test were not different between the 28x15 and the 28x9 match protocols (p > 0.05). A significant difference was observed for lactate concentration from pre- to post-match (p < 0.05) in both protocols (28x15 and 28x9); however, there was no significant interaction between protocols. A similar session-RPE mean score (28x15: 7.2 ± 1.4 and 28x9: 6.6 ± 1.4) was detected for both protocols (p > 0.05, ES=0.41). In summary, the results of the current study suggest that the different court areas induced similar responses. Although there was no significant difference in effort perception, players tended to perceive a greater effort in the larger court size.

Unilateral plantar flexors static-stretching effects on ipsilateral and contralateral jump measures

The aim of this study was to evaluate the acute effects of unilateral ankle plantar flexors static-stretching (SS) on the passive range of movement (ROM) of the stretched limb, surface electromyography (sEMG) and single-leg bounce drop jump (SBDJ) performance measures of the ipsilateral stretched and contralateral non-stretched lower limbs. Seventeen young men (24 ± 5 years) performed SBDJ before and after (stretched limb: immediately post-stretch, 10 and 20 minutes and non-stretched limb: immediately post-stretch) unilateral ankle plantar flexor SS (6 sets of 45s/15s, 70-90% point of discomfort). SBDJ performance measures included jump height, impulse, time to reach peak force, contact time as well as the sEMG integral (IEMG) and pre-activation (IEMGpre-activation) of the gastrocnemius lateralis. Ankle dorsiflexion passive ROM increased in the stretched limb after the SS (pre-test: 21 ± 4° and post-test: 26.5 ± 5°, p < 0.001). Post-stretching decreases were observed with peak force (p = 0.029), IEMG (P<0.001), and IEMGpre-activation (p = 0.015) in the stretched limb; as well as impulse (p = 0.03), and jump height (p = 0.032) in the non-stretched limb. In conclusion, SS effectively increased passive ankle ROM of the stretched limb, and transiently (less than 10 minutes) decreased muscle peak force and pre-activation. The decrease of jump height and impulse for the non-stretched limb suggests a SS-induced central nervous system inhibitory effect. Key pointsWhen considering whether or not to SS prior to athletic activities, one must consider the potential positive effects of increased ankle dorsiflexion motion with the potential deleterious effects of power and muscle activity during a simple jumping task or as part of the rehabilitation process.Since decreased jump performance measures can persist for 10 minutes in the stretched leg, the timing of SS prior to performance must be taken into consideration.Athletes, fitness enthusiasts and therapists should also keep in mind that SS one limb has generalized effects upon contralateral limbs as well.

The effects of specific athletic training on path selection while running

Apertures that are smaller than 1.3 times the shoulder width (SW) require that individuals make an adjustment to their normal walking behavior [6]. When given a choice, individuals will choose to avoid apertures smaller than this ratio, rather than rotate their shoulders and walk through [7]. Research has yet to determine whether this choice in path selection can be influenced by the speed at which one approaches the aperture or by experience/training. Therefore, the current study investigated whether approach speed and/or specific athletic training influences the choice in path selection. Specifically-trained athletes (n=6) and non-trained (n=6) young adults ran toward a visible goal placed at the end of the path and avoided an aperture (created by two poles) placed along the midline of the path. The separation between the poles ranged between 0.6 and 1.8 times each participant's SW, in increments of 0.2. Participants were permitted to either run through or around the aperture to get to the end goal. Results demonstrated that regardless of training experience, participants ran around apertures smaller than 1.4× the SW and ran through apertures larger than this ratio. Increased approach speed (i.e., running) therefore appears to elicit similar aperture crossing behaviors as walking [2,3,6,7]. Additionally, when faced with the choice to run around or to run through apertures, individuals who are specifically-training to run through small spaces chose similar paths as individuals who are not trained to do so. Therefore, specific training does not appear to influence voluntary path selection.