Influence of hamstring muscle extensibility on spinal curvatures in young athletes

Do floating toes relate with the ability to perform the deep squat test among baseball players with throwing injury?

Relationship between ability to perform the deep squat test (DST) and floating toes among baseball players with disabled throwing shoulder/elbow was retrospectively investigated. Players performed the DST by fully squatting while having their arms crossed in front of their chest without lifting the heel off the floor or falling backwards. Floating toes were evaluated if all the toes were in contact with the mat or not. The relationship between ability to perform the DST and prevalence of floating toes was statistically analysed. Sixty-three players (69.2%) were unable to perform the DST. Floating toes were observed in 74 players (81.3%). Players with inability to perform the DST had significantly higher prevalence of floating toes (58 players, 92.1%), compared with those who were able to perform the test (16 players, 57.1%) (p < 0.001). Floating toes may relate with inability to perform the DST among baseball players with disabled throwing shoulder/elbow.

The occurrence of flexion-relaxation phenomenon in elite cyclists during trunk forward bending

Flexion-relaxation phenomenon (FRP) is a well-known phenomenon in spinal extensor muscles. According to the literature, prolonged flexed posture leads to creep phenomenon and affects the active and passive neuromuscular control of the spinal column. The purpose of this study was to investigate FRP occurrence in elite cyclists that prolonged flexion posture is an integral part of their professional life. Their muscles' contraction pattern during forward bending was also compared. Electromyography (EMG) was recorded during flexion and extension from standing position in thoracic erector spinae (TES), lumbar erector spinae (LES) and gluteus maximus (Gluteus max) in 15 healthy male elite cyclists. In addition, the kinematic data related to the trunk angles were simultaneously recorded by a motion analysis system. Two-way ANOVA was used to assess the effects of muscle group and direction of movement on maximum amplitude of EMG activity. Among 15 cyclists, FRP was detectable in 60%, 87% and 73% of the participants in TES, LES and Gluteus max, respectively, and happened between 74% and 82% of the trunk flexion. There was no statistically significant difference in onset and offset of muscles FRP. Despite prolong hyper kyphotic posture, FRP was identifiable in TES, LES and Gluteus max muscles of elite cyclists.

The association of hamstring tightness with lumbar lordosis and trunk flexibility in healthy individuals: gender analysis

Objectives: The purpose of this study was to investigate if there is a relation between hamstring tightness and lumbar lordosis as well as trunk flexibility based on gender differences and to analyze the differences in hamstring tightness, lumber lordosis and trunk flexibility in healthy adults. Methods: One hundred young healthy adults were recruited and distributed into 2 equal groups according to gender: group A (female group) and group B (male group). Hamstring tightness (HT) was measured by Active Knee Extension (AKE) test and Straight Leg Raise (SLR) test, the angle of lumbar lordosis was measured with a flexible ruler from standing position and trunk flexion flexibility (TFF) was measured by Fingertip-to-Floor Test. Results: There was a significant correlation between TFF and both measures of HT (SLR, p = 0.001; AKE, p = 0.001) in females. While, there was a non-significant correlation in males (SLR, p = 0.900; AKE, p = 0.717). Moreover, there was a non-significant correlation between lumbar lordosis and HT measures in both groups as (p > 0.05). Furthermore, there were significant differences between males and females in hamstring flexibility, TFF and lumbar lordosis as (p < 0.05). Conclusion: Gender differences in the relationship between hamstring tightness and trunk flexion flexibility are significant. However, there was no significant difference between males and females in the relationship between hamstring tightness and lumbar lordosis.

Effects of cycling on the morphology and spinal posture in professional and recreational cyclists: a systematic review

The aim was to know if cycling affects spinal morphology in postures off the bicycle, such as adapting the spinal curvatures on the bicycle depending on the handlebar type and position on the handlebars. A systematic review was conducted following the PRISMA guidelines. The studies selected met the following criteria: a) the study design was cross-sectional or longitudinal (experimental or cohorts); b) the study evaluated the sagittal morphology of the spine on the bicycle; c) the study included healthy and trained participants without injuries or cyclists reporting low back pain. Fifteen studies reported that a greater pelvic tilt was observed that when the handlebar was in a lower position. Sixteen studies found that lumbar kyphosis was greater when the handlebar grip was lower and farther from the saddle. Twelve studies reported that a tendency towards greater thoracic flexion as the time spent pedalling on the bicycle increased. In conclusion, the practice of cycling produces adaptations in the morphology of the spine of the cyclist compared to non-cyclists, such as an increase in pelvic tilt and a greater capacity for lumbar flexion in trunk flexion positions, and a greater thoracic kyphosis in the standing position.

Influences of limited flexibility of the lower extremities and occurrence of low back pain in adolescent baseball players: A prospective cohort study

BACKGROUND

Limited flexibility of the lower extremities, such as hamstring tightness, has long been suggested as a physical risk factor for low back pain among adolescent athletes. However, few prospective cohort studies have examined the direction of causality for this relationship. This prospective cohort study investigated the relationship between limited flexibility of the lower extremities and the occurrence of low back pain among high school baseball players.

METHODS

Participants comprised 335 high school baseball players from 43 high school baseball teams who had undergone baseline medical evaluations (a self-completed questionnaire and physical examination). Occurrence of low back pain during a 1-year follow up, and associations with measurements of flexibility of the lower extremities such as straight-leg-raising angle (hamstring tightness), Thomas test (iliopsoas tightness), heel-buttock-distance (quadriceps tightness), and passive range of motion of the hip were investigated.

RESULTS

In total, 296 players (88.4%) participated in the 1-year follow-up survey, with 147 of the 296 players (49.7%) reporting the occurrence of low back pain during follow-up. The number of players with low back pain during follow-up peaked in November, then decreased and was lowest in June. After adjusting for factors associated with low back pain using logistic regression modeling, a significant association between hamstring tightness on the non-throwing arm side and low back pain (odds ratio 2.86, 95% confidence interval 1.17-6.94; P = 0.018) was found.

CONCLUSIONS

Hamstring tightness on the non-throwing arm side was identified as a potential risk factor for low back pain in high school baseball players. These results may provide guidance in the development of future prevention programs.

Changing the pattern of the back-muscle flexion-relaxation phenomenon through flexibility training in relatively inflexible young men

Although several studies have investigated the back-muscle flexion-relaxation phenomenon (FRP), the effect of individual flexibility on the FRP has been discussed infrequently, with very limited data on the influence of flexibility training on the FRP. This study thus examined the effect of flexibility training on the change of back-muscle FRP pattern in relatively inflexible young men. We collected and analyzed the valid data from 20 male participants (10 each with high and low flexibility included in the control and trained groups, respectively) when flexing their trunks at seven trunk flexion positions (0°-90°, in increments of 15°); their erector spinae and hamstring activation, pelvic tilt, and lumbosacral angle were then recorded. After 7 weeks of flexibility training for the low-flexibility group, no difference in flexibility was discovered between this group and the control (originally high-flexibility) group. The trunk flexion experiment was then repeated. The results showed that before the training stage, the low-flexibility group had lower erector spinae and higher hamstring activation, a larger pelvic tilt, and a smaller lumbosacral angle. By contrast, after training, the erector spinae and hamstring activation, pelvic tilt, and lumbosacral angle were significantly changed, and no intergroup differences were observed in FRP patterns. The study results suggest that flexibility training changes lumbopelvic movement and thereby reduces the degree of the back-muscle FRP when trunk flexion is performed.

The Potential Role of Hamstring Extensibility on Sagittal Pelvic Tilt, Sagittal Spinal Curves and Recurrent Low Back Pain in Team Sports Players: A Gender Perspective Analysis

It is assumed that mechanical restriction of hamstring tightness disrupts sagittal spine–pelvis–leg alignment and alters the lumbar–pelvic rhythm predisposing to low back pain (LBP) in athletes; however, this association is not clear. A prospective cross-sectional cohort study was conducted to determine the influence of hamstring extensibility (HE) on sagittal pelvic tilt, sagittal spinal curves, and LBP in 94 soccer and basketball players (61 man and 33 woman) with (n = 36) and without recurrent LBP (n = 58). Descriptive analysis displayed significant gender differences for HE, sagittal pelvic tilt, and lumbar curve. Differences were found between the low-HE and high-HE groups in lumbosacral angle in for the maximum trunk forward flexion (LH-MTFP). Low-HE was associated with LH-MTFP, lumbar curve and LBP in male players (p ≤ 0.023). In female players, LH-MTFP and lumbar curve were associated with low-HE (p ≤ 0.020). Low-HE predicted LH-MTFP (p = 0.000; OR = 65.6950) and LBP (p = 0.028; OR = 13.915) in male players. The decision tree analysis showed that 50.8% of the players were classified with restricted LH-MTFP, 77.4% with low-HE among male players. The 100% of male players with recurrent LBP had low-HE. The 65% of female players with low-HE had restricted LH-MTFP. Measurement of HE, lumbar curve, and LH-MTFP are important in making training decisions for to reduce the incidence of recurrent LBP in soccer and basketball players.

Anthropometrics, flexibility and training history as determinants for bicycle configuration

Intrinsic factors such as leg length, arm length, flexibility and training history are factors that may be relevant to the optimisation of the individual bicycle configuration process. Bike fitting methods do not always take all these variables into account, and as yet there have been limited studies examining how these variables can affect the cyclist's position on the bicycle. The main aims of this study were to establish how individual anthropometrics, training history and flexibility may influence cyclists' freely chosen bicycle configuration, and to determine the full-body static flexion angles chosen by cyclists on the bicycle.

Fifty well-trained male cyclists were recruited for the study. A multivariate linear regression analysis was performed to predict the four main configurations of a bicycle (saddle height, saddle setback, handlebar reach and handlebar drop) based on individual anthropometrics, flexibility and training history. Average joint kinematic ranges for the knee (36°±7°) and elbow (19°±8°) joint supported previous recommendations. Hip (77°±5°) and shoulder (112°±7°) joint angles should be determined as true clinical joints.

Trochanteric leg length (p < 0.01), Knee Extension Angle test (p < 0.01) and mSchober test (p = 0.04) were significant predictors for determining saddle height. Hamstring flexibility can be used to predict handlebar drop (p = 0.01).

A cyclist who wishes to adopt a more aerodynamic position with an increased handlebar drop should aim to improve their hamstring flexibility.

Injuries Associated with the Practice of Calm Water Kayaking in the Canoeing Modality

Knowing the most frequent injuries in canoeists is important, considering the consequences for the athlete’s sports career, health, and labour, social and economic life. Therefore, the aim of this study was to describe the most frequent injuries among high-level canoeists and the intrinsic variables of the sport’s practice (years of practice, number of training sessions per week, and stretching habit) that can influence the appearance of such injuries. An observational, transversal, and retrospective epidemiological study was carried out with 122 canoeists that completed a sport injuries questionnaire (number, body area, type, and severity of injuries). The ratio of injuries per participant was 1.1 injuries/year in men; and 1.5 injuries/year in women. Shoulder injuries were the most frequent, followed by knee injuries (in women) and lower back (in men), and the other segments of the upper limbs. In men, injuries occurred more frequently in the central period of training sessions and in women during the last 15 min of training sessions. Then, there is a common profile of injuries in canoeists: Being a female, having more years of sports practice, and never executing stretching exercises are associated with predisposing factors to injuries.

Effect of 9-month Pilates program on sagittal spinal curvatures and hamstring extensibility in adolescents: randomised controlled trial

The percentage of spine misalignment increases during the childhood and adolescence stages. The Pilates method has been associated with an improvement in the sagittal spine disposition, but no studies have been conducted on adolescents. Therefore, the present study aimed to evaluate the effectiveness of a 9-month Pilates exercise program (PEP) on hamstring extensibility and sagittal spinal curvatures on adolescents. This randomised controlled trial included 236 adolescents. The experimental group (EG) received a PEP (9 months, 2 sessions/week, 15 minutes/session). The control group (CG) did not receive any intervention. Hamstring extensibility was measured with the passive and active straight leg raise and toe-touch tests. Sagittal spinal curvatures and pelvic tilt was assessed in relaxed standing, active alignment and toe-touch test positions. The EG had significant changes in hamstring extensibility, lumbar curvature and pelvic tilt in standing sagittal curvature. The CG became significantly worse in thoracic kyphosis in standing. This study provides evidence of nine-months of a PEP increased the hamstring extensibility; averted the increase of the thoracic curvature, and decreased the curvature of the lumbar lordosis and pelvic tilt in standing position; avoided a greater increase of thoracic curvature in active alignment in standing position; and avoided the increase of thoracic curvature in trunk flexion.

Relationship Between Spinal-Pelvic Sagittal Balance and Pelvic-Femoral Injuries in Professional Soccer Players

Background

Pelvic-femoral injuries are a common problem in football (soccer) players. However, the risk factors for these injuries are unclear. Our knowledge of spinal-pelvic sagittal balance has increased considerably over the past few years, notably as a result of new radiographic techniques such the EOS radiographic imaging system.

Purpose

To investigate the link between spinal-pelvic sagittal balance on EOS imaging and the incidence of pelvic-femoral injuries.

Study Design

Cohort study; Level of evidence, 2.

Methods

Players in a League 1 professional soccer team were observed for 5 consecutive seasons. All players included in the study underwent EOS radiographic imaging. All acute and microtraumatic injuries to the pelvic-femoral complex were recorded prospectively: hamstrings, psoas, quadriceps, adductors, obturators, and pubic symphysis. We analyzed the relationship between injury incidence and key radiographic parameters involved in pelvic balance.

Results

A total of 61 players were included (mean age, 24.5 years; n = 149 injuries; mean pelvic tilt, 9.08° ± 5.6°). A significant link was observed between the incidence of pelvic-femoral injuries and pelvic tilt (P = .02). A significant link was also observed between the incidence of acute pelvic-femoral injuries and pelvic tilt (P = .05). In both cases, a high pelvic tilt was associated with a low incidence of injuries.

Conclusion

In professional soccer players, a low pelvic tilt was associated with a high incidence of all pelvic-femoral injuries as well as acute pelvic-femoral injuries. These results could lead to new preventive methods for these musculotendinous injuries through physical therapy.

The effect of sagittal hip angle on lumbar and hip coordination and pelvic posterior shift during forward bending

PURPOSE

The purpose of this study was to investigate the effects of dynamic sagittal hip angle on lumbar and hip coordination and pelvic posterior shift during forward bending.

METHODS

A total of 44 asymptomatic younger female volunteers were recruited to this study. Following measurement of trunk forward bending, participants were divided into three groups based on hip flexion angle: group 1, < 30°; group 2, ≥ 30° and < 50°; and group 3, ≥ 50°. Lumbar spine and hip coordination and pelvic backward shift were recorded during trunk forward bending using a three-dimensional ultrasonic motion analysis system.

RESULTS

Pelvic and total angles increased with hip angle (group 3 > group 2 > group 1; p = 0.003 and p < 0.001, respectively), whereas lumbar/hip and pelvic/hip angle ratios decreased significantly (p < 0.001). The degree of pelvic posterior shift increased to a limited extent, whereas the pelvic posterior shift/hip angle ratio decreased significantly (p < 0.05).

CONCLUSIONS

Asymptomatic subjects with limited hip flexion showed reduced total pelvic anterior rotation and greater relative proportion of pelvic motion than insufficient hip motion. These subjects tended to increase the pelvic posterior shift/hip angle ratio during trunk forward bending, possibly increasing passive tension by elongating the hamstring muscles to increase hip motion. The results of this study provide information that will improve the assessment of lumbar spine and hip coordination patterns and facilitate movement strategies by determining the specific requirements of individuals. These slides can be retrieved under Electronic Supplementary Material.

Effects of Latin style professional dance on the spinal posture and pelvic tilt

BACKGROUND

Systematic repetition postures adopted during trainings could generate alterations in the sagittal spinal curvatures.

OBJECTIVE

The purposes were: 1) to analyse the sagittal spinal curvatures and pelvic tilt in Latin American style dancers; 2) to compare the spinal sagittal mobility and hamstring muscle extensibility between Latin American style dancers and non-dancers; and 3) to evaluate the influence of wearing dance shoes upon the sagittal spine posture in standing.

METHODS

A total of 20 Latin American style professional dancers and 20 non-dancers (control group) were evaluated during standing, relaxed sitting, maximal trunk flexion with knees flexed and extended, lying prone, and maximal trunk extension. Additionally, dancers were analysed while standing barefoot, and wearing heeled-shoes, during forward walking and the paso-doble posture. The hamstring muscle extensibility was evaluated by the active knee extension test.

RESULTS

The spinal morphology in Latin American style professional dancers is characterised by lower thoracic kyphosis, lumbar lordosis and anterior pelvic tilt in the standing posture as well as a flexible spine, especially in flexion postures, in addition to suitable hamstring muscle extensibility.

CONCLUSIONS

The spinal morphology of Latin American style professional dancers is characterised by lower thoracic kyphosis and lumbar lordosis and anterior pelvic tilt in the standing posture as well as a flexible spine, especially in flexion postures, and suitable hamstring muscle extensibility.

Differences in Anthropometry, Biological Age and Physical Fitness Between Young Elite Kayakers and Canoeists

The aim of this study was to determine the anthropometric and physical characteristics of youth elite paddlers and to identify the differences between kayakers and canoeists. A total of 171 male paddlers (eighty-nine kayakers and eighty-two canoeists), aged 13.69 ± 0.57 years (mean ± SD) volunteered to participate in this study. The participants completed basic anthropometric assessments (body mass, stretch stature, sitting height, body mass index, maturity level, sum of 6 skinfolds and fat mass percentage) as well as a battery of physical fitness tests (overhead medicine ball throw, counter movement jump, sit-and-reach and 20 m multi-stage shuttle run tests). The anthropometric results revealed a significantly larger body size (stretch stature and sitting height) and body mass in the kayakers (p < 0.01) as well as a more mature biological status (p = 0.003). The physical fitness level exhibited by the kayakers was likewise significantly greater than that of the canoeists, both in the counter movement jump and estimated VO2max (p < 0.05), as well as in the overhead medicine ball throw and sit-and-reach test (p < 0.01). These findings confirm the more robust and mature profile of youth kayakers that might be associated with the superior fitness level observed and the specific requirements of this sport discipline.

In vivo relationship between pelvis motion and deep fascia displacement of the medial gastrocnemius: anatomical and functional implications

Different authors have modelled myofascial tissue connectivity over a distance using cadaveric models, but in vivo models are scarce. The aim of this study was to evaluate the relationship between pelvic motion and deep fascia displacement in the medial gastrocnemius (MG). Deep fascia displacement of the MG was evaluated through automatic tracking with an ultrasound. Angular variation of the pelvis was determined by 2D kinematic analysis. The average maximum fascia displacement and pelvic motion were 1.501 ± 0.78 mm and 6.55 ± 2.47 °, respectively. The result of a simple linear regression between fascia displacement and pelvic motion for three task executions by 17 individuals was r = 0.791 (P < 0.001). Moreover, hamstring flexibility was related to a lower anterior tilt of the pelvis (r = 0.544, P < 0.024) and a lower deep fascia displacement of the MG (r = 0.449, P < 0.042). These results support the concept of myofascial tissue connectivity over a distance in an in vivo model, reinforce the functional concept of force transmission through synergistic muscle groups, and grant new perspectives for the role of fasciae in restricting movement in remote zones.

Influence of Hamstring Tightness in Pelvic, Lumbar and Trunk Range of Motion in Low Back Pain and Asymptomatic Volunteers during Forward Bending

STUDY DESIGN

Cross-sectional study.

PURPOSE

To verify the association of hamstring tightness and range of motion in anterior pelvic tilt (PT), lumbar motion (LM), and trunk flexion (TF) during forward bending.

OVERVIEW OF LITERATURE

Increased hamstring stiffness could be a possible contributing factor to low back injuries. Clinical observations have suggested that hamstring tightness influences lumbar pelvic rhythm. Movement restrictions or postural asymmetry likely lead to compensatory movement patterns of the lumbar spine, and subsequently to increased stress on the spinal soft tissues and an increased risk of low back pain (LBP).

METHODS

Hamstring muscle tightness was measured using the self-monitored active knee extension (AKE) test. A bubble inclinometer was used to determine the range of motion of PT, LM, and TF during forward bending. Statistical analysis included descriptive statistics, comparisons between groups and a correlation between hamstring tightness (AKE) and anterior PT, TF, and regional LM with p≤0.05.

RESULTS

The LBP group was composed of 36 participants, and the asymptomatic group consisted of 32 participants. The mean for PT in the control group was 66.7°, 64.5° for LM and 104.6° for TF. Respective values in the symptomatic group were 57.0°, 79.8°, and 82.2°.

CONCLUSIONS

Participants with LBP showed restriction in the pelvis and TF range of motion, but had higher amplitudes in the lumbar spine during forward bending.

Effects of kinesio taping on lumbopelvic-hip complex kinematics during forward bending

[Purpose] The aim of this study was to investigate the effect of kinesio taping (KT) on the kinematics of the lumbo-pelvic-hip complex during forward bending by individuals with reduced hamstring extensibility. [Subjects] Eighteen males with reduced hamstring extensibility were randomly assigned to one of two groups:, the hamstring KT group (n=9), or the sham KT group (n=9). [Methods] The kinematics of the lumbopelvic-hip complex during lumbar forward bending was measured using a motion capture system before and after applying KT. [Results] The angle of lumbar flexion during late lumbar forward bending increased significantly post-KT compared to pre-KT measurements in the hamstring KT group. [Conclusion] These findings suggest that KT does not directly affect an individual’s movement during lumbar forward bending.

The Relationship Between Hamstring Muscle Extensibility and Spinal Postures Varies with the Degree of Knee Extension

The aim was to determine the relationship between hamstring muscle extensibility and sagittal spinal curvatures and pelvic tilt in cyclists while adopting several postures. A total of 75 male cyclists were recruited for this study (34.79 ± 9.46 years). Thoracic and lumbar spine and pelvic tilt were randomly measured using a Spinal Mouse. Hamstring muscle extensibility was determined in both legs by a passive knee extension test. Low relationships were found between hamstring muscle extensibility and spinal parameters (thoracic and lumbar curvature, and pelvic tilt) in standing, slumped sitting, and on the bicycle (r= .19;P> .05). Significant but low relationships were found in maximal trunk flexion with knees flexed (r= .29;P< .05). In addition, in the sit-and-reach test, low and statistically significant relationships were found between hamstring muscle extensibility for thoracic spine (r= –.23;P= .01) and (r= .37;P= .001) for pelvic tilt. In conclusion, hamstring muscle extensibility has a significant relationship in maximal trunk flexion postures with knees flexed and extended, but there are no relationships while standing or on the bicycle postures.