A biomechanical evaluation of the combined elevation test

ObjectivesTo evaluate biomechanically the relationships between the outcome of the Combined Elevation Test, its component joint motions, and thoracic spine angles.DesignCross-sectional study.SettingLaboratory.Participants18 elite swimmers and triathletes (11 males and 7 females).Main outcome measuresCombined Elevation Test outcome in forehead and chin positions. Individual joint contributions to test outcome.ResultsNo sex differences were found in test components, or between head positions. Test outcome was greater in the forehead position than the chin position (34.3 cm vs 30.2 cm; p < 0.001). The variables most strongly associated with test outcome were glenohumeral joint flexion (r = 0.86–0.97; p < 0.001), and shoulder retraction (r = 0.75–0.82; p < 0.001). Total thoracic spine angle related strongly to test outcome in females (r = −0.77 to -0.88; p < 0.05), but not in males (r = −0.17 to -0.24; p > 0.05).ConclusionsThe Combined Elevation Test is an effective screening tool, measuring upper limb mobility into shoulder flexion and scapula retraction in both sexes, and thoracic extension in women. It is recommended that the test be performed in the forehead position. If a subject performs poorly on the test, follow up assessments are required to identify the impairment location.     

Changes in joint kinematics and dynamic postural stability with free and restricted arm movements in children

BackgroundArm movements make a substantial and functionally relevant contribution to quiet standing and dynamic balance tasks. The impact of restricted arm movements on balance control is particularly important for children as their postural control system is not fully matured.Research questionThis study investigated the effects of arm movements on lower body joint kinematics and dynamic postural stability during anterior and lateral dynamic movements in children.MethodsEighteen boys (age, 10.1 ± 1.6 years) completed an anterior and a lateral jump-landing task under two different verbally conveyed instructions of arm position; (1) arms placed flat across the chest touching the contralateral shoulder (i.e., restricted arm movement) and (2) arm movement without restriction. Lower body joint kinematics were recorded and used to calculate mean joint position, joint range of motion (ROM) and joint movement variability.ResultsRestricting arm movements resulted in a reduction of joint movement variability and joint ROM of the pelvis during the lateral jump (p <0.05), but increased joint movement variability and joint ROM of the pelvis during the anterior jump (p <0.05).SignificanceThe reduced joint movement variability and joint ROM with restricted arm movements during the lateral jump may represent a potential compensatory ‘stiffenin strategy’, whilst the increase during the anterior jump suggest an exploratory strategy. These novel findings highlight that it is important for children to be introduced to different dynamic task constraints so that they can learn to control and organise the motor system degrees of freedom appropriately.     

Are professional handball players at risk for developing a glenohumeral internal rotation deficit in their dominant arm?

Objectives: Overhead athletes, such as baseball players, have been shown to have adaptive changes in the shoulder range of motion (ROM) of their dominant arm. Professional handball players are a unique subtype of overhead athletes with very different demands from baseball players. The aim of this study was to determine if professional handball players demonstrate differences in shoulder ROM between their dominant and non-dominant arm and try to relate them with new variables.

Methods: Fifty professional male handball players were included and completed a questionnaire regarding age at which they started to play, number of hours they practice a week, field position and arm dominance. ROM measurements were performed including forward flexion (FF), external rotation with the shoulder in abduction (ABER) and with adducted arm (ADER) and internal rotation with shoulder in abduction (IR). Statistical analysis was performed to determine differences in ROM between the dominant and non-dominant shoulder and if there is a relationship between these differences and shoulder load or field position.

Results: The dominant arm showed decreased internal rotation (47 vs. 56 degrees, p < 0.001) and increased external rotation both with the arm abducted (99 vs. 88 degrees, p < 0.001) and at the side (62 vs 57 degrees, p = 0.001). This was not correlated with shoulder load for any movement (FF, p = 0.980; ABER, p = 0.741; ADER, p = 0.803; IR, p = 0.085) but was dependent on field position with first line players showing the highest internal rotation deficit (13 degrees vs. 6–7 degrees in the other field positions, p = 0.013).

Conclusion: This study showed that professional male handball players with a first line position have a significant risk for developing a glenohumeral internal rotation deficit, similar to the phenomenon seen in baseball pitchers.     

Analysis of the presence and influence of Glenohumeral Internal Rotation Deficit on posterior stiffness and isometric shoulder rotators strength ratio in recreational and amateur handball players

ObjectiveTo determine whether recreational and amateur handball players exhibit Glenohumeral Internal Rotation Deficit (GIRD), and if it is accompanied by posterior stiffness and changes in shoulder rotators strength.DesignCross-Sectional Study;SettingResearch laboratory.ParticipantsIndoor and beach handball players, members of handball teams or engaged in some handball recreational group.Main outcome measuresRange of motion (ROM) of internal rotation (IR) and horizontal adduction (HA), and isometric internal and external rotators strength. Based on the ROM of internal rotation, they were allocated to groups with and without GIRD.ResultsThe dominant shoulder of GIRD group obtained a lower ROM of IR compared to the non-dominant shoulder of the same group (p < 0.01) and to the dominant (p = 0.02) and non-dominant (p = 0.01) shoulders of the group without GIRD. Less horizontal adduction was observed in both groups (p = 0.01), as well as greater external rotator strength (p = 0.01) and external/internal rotators strength ratio (p < 0.04) in the dominant shoulder. The rotators strength ratio was greater in GIRD group (p < 0.01).ConclusionsThe present study showed the dominant shoulder had greater posterior stiffness and external rotator strength, regardless of GIRD. Also the group with GIRD showed higher rotators strength ratio.     

The effects of foot orthosis and low-dye tape on lower limb joint angles and moments during running in individuals with pes planus

BackgroundPes Planus or Flat feet is one of the most common lower limb abnormalities. When runners with this abnormality participate in recreational running, interventional therapies could help in pain alleviation and enhance performance. To determine the most effective treatment, however, a biomechanical examination of the effects of each treatment modality is required.Research questionThe aim of the present study was to investigate the effects of Foot Orthoses (FOs) and Low-Dye Tape (LDT) on lower limb joint angles and moments during running in individuals with pes planus.Methodskinematic and kinetic data of 20 young people with pes planus were measured during running in three conditions: (1) SHOD (2) with shoes and FOs (3) with shoes and LDT. One-way repeated measure ANOVA was used to investigate the impacts of the FOs and LDT on the lower limb joint angles and moments throughout the stance phase of the running cycle.ResultsThe results showed that FOs reduced ankle eversion compared to SHOD and LDT (P < 0.001) and decreased the dorsiflexion angle (P = 0.005) and the plantarflexor moment compared to the SHOD (P < 0.001). FOs increased knee adduction angle (P = 0.021) and knee external rotator moment (P < 0.001) compared to both conditions and increased knee extensor and abductor moments compared to SHOD (P < 0.001). At the hip joint, FOs only increased hip external rotation compared with the LDT condition (P = 0.031); and LDT increased hip extensor moment compared to SHOD and FOs (P = 0.037) and also increased hip adduction angle compared to SHOD (P = 0.037).SignificanceFOs with a medial wedge appears to increase the external knee adduction moment and knee adduction angles, which are risk factors for the development and progression of knee osteoarthritis. Further, usage of FOs seems to reduce the ankle joint role in propulsion as it impacts the ankle sagittal angles and moments.     

The effect of shoulder muscle fatigue on active repositioning acuity and scapulothoracic resting alignment: A systematic review with meta-analysis

ObjectivesThe purpose was to synthesize the current evidence for the impact of muscle fatigue on measures for active repositioning task of the glenohumeral or scapulothoracic movements including the absolute error and/or scapulothoracic resting alignment.MethodsWe searched the PubMed, EMBASE, MEDLINE, CINAHL, SCOPUS, SportDiscuss and the Cochrane library databases. We included papers using a fatiguing task as part of their experimental design. Meta-analyses were undertaken for the active repositioning acuity of the glenohumeral outer/inner range of external rotation, glenohumeral inner range of internal rotation and scapulothoracic resting alignment in the scapular upward/downward rotation, anterior/posterior tilt and protraction/retraction planes. Qualitative data synthesis with standardized mean difference (SMD) was also conducted.ResultsThere was a significantly pooled SMD, −2.10 (95% confidence interval −2.57 to −1.63), P < 0.001) in active repositioning acuity of the glenohumeral outer range of external rotation before and after a fatiguing task. However, the pooled SMD in active repositioning acuity for other glenohumeral movements and scapulothoracic resting positions were not significant (P > 0.05).ConclusionShoulder muscle fatigue impairs active repositioning acuity of the glenohumeral outer range of external rotation. Conversely, the current evidence does not support such impairment for the remaining glenohumeral movements and scapulothoracic resting alignments..     

The relationship between latissimus dorsi stiffness and altered scapular kinematics among asymptomatic collegiate swimmers

ObjectivesTo determine the strength of the relationship between latissimus dorsi stiffness and altered scapular kinematics among swimmers.DesignCross sectional.SettingLaboratory.ParticipantsNineteen NCAA Division III swimmers (7 male, 12 female) (age = 18.8 ± 0.9 years, height = 174.7 ± 8.9 cm, mass = 71.6 ± 11.9 kg) volunteered to participate. Subjects had no recent history of upper extremity pathology or any previous surgery.InterventionsWe measured latissimus dorsi stiffness of the dominant arm while in a lengthened position with a myotonometer. We used an electromagnetic tracking device with specialized software to measure scapular kinematics at humeral elevation angles of 30°, 60°, 90°, and 110° within the scapular plane.Main outcome measuresLatissimus dorsi stiffness and scapular upward/downward rotation, internal/external rotation, and anterior/posterior tilt.ResultsLatissimus dorsi stiffness showed moderate-to-good relationships with increased scapular upward rotation (r > ?0.63, P < 0.002) and posterior tilt (r > ?0.62, P < 0.004) at all four angles of humeral elevation. Increased latissimus dorsi stiffness also showed moderate-to-good relationships with decreased scapular internal rotation at humeral elevation angles of 60° (r = 0.47, P = 0.03) and 90° (r = 0.54, P = 0.01).ConclusionsOur results suggest there are several moderate-to-good relationships between increased latissimus dorsi stiffness in swimmers and altered scapular upward rotation, internal rotation, and posterior tilt at various angles of humeral elevation. If latissimus dorsi stiffness is not addressed subsequent scapular alterations, which have been associated with shoulder dysfunction, may occur.     

Glenohumeral joint: internal and external rotation range of motion in javelin throwers

OBJECTIVE: To assess differences in glenohumeral joint rotatory range of movement in javelin throwers between the throwing and non-throwing arm. METHOD: A universal 360 degrees goniometer was used to assess glenohumeral joint external and internal rotation range in 90 degrees of shoulder abduction in a group of ten senior international javelin throwers. RESULTS: Both arms had significantly greater degrees of external than internal rotation (p < 0.01), and the throwing arm had significantly greater range of external rotation than the non-throwing arm (p < 0.01). CONCLUSIONS: The presence of an excessive range of external rotation in the throwing shoulder has the potential to increase eccentric load on the rotator cuff muscles and strain on the passive restraints of the glenohumeral joint. Both of these factors have been implicated in the pathological processes leading to injury in the overhead throwing athlete.


     

Comparison of hip joint range of motion in professional youth and senior team footballers with age-matched controls: An indication of early degenerative change?

ObjectivesTo determine if there is evidence of abnormal hip joint range of motion (ROM) in youth and senior team professional footballers compared with matched controls.DesignA case control study design was used.Participants40 professional footballers (20 youth and 20 senior team) and 40 matched control subjects.Main outcome measuresBilateral measurements of passive hip internal rotation (IR), external rotation (ER), flexion, abduction and extension were made together with Faber's test and the hip quadrant.ResultsYouth and senior footballers had significantly less IR and Faber's range and significantly higher abduction than their respective controls (p < 0.001). Senior footballers also had significantly reduced IR (p < 0.05) and Faber's (p < 0.001) than the youth team. A higher proportion of senior footballers had positive hip quadrants (45% of all hips) compared to all other groups. No significant difference in hip ROM was found between dominant and non-dominant legs.ConclusionsA specific pattern of hip ROM was found in professional footballers which appeared to be different from controls. These changes may demonstrate the early stages of hip degeneration to which it has been shown ex-professional players are prone to. Hip joint ROM exercises may be necessary in these players to restore normal movement and prevent the onset of hip osteoarthritis (OA).     

Shoulder strength, power, and endurance in college tennis players.

Twenty-four college tennis players were tested for bilateral shoulder internal/external rotation strength on a Cybex 340 isokinetic dynamometer; they were positioned supine with the glenohumeral joint abducted to 90 degrees. Subjects produced significantly (P less than 0.01) more torque in internal rotation at 60 and 300 deg/sec in the dominant arm compared to the nondominant arm. Subjects also produced significantly more power in internal rotation at 60 deg/sec in the dominant arm. No significant differences between the dominant and nondominant arms were seen in internal rotation power at 300 deg/sec or in the internal rotation endurance ratio. No significant differences were seen in external rotation on any measurement. By significantly increasing the strength of the dominant shoulder in internal rotation without subsequent strengthening of the external rotators, muscle imbalances may be created in the dominant arm that could possibly affect the tennis player's predisposition to injuries caused by overloading of the shoulder joint. This study suggests that external rotation strengthening exercises should be implemented in tennis conditioning programs to maintain muscle strength balance, and possibly reduce the chance of overload injury.     

A survey of glenohumeral joint rotational range and non-specific shoulder pain in elite cricketers

ObjectivesTo determine if a glenohumeral joint internal rotation range of motion difference (IRD) and external rotation difference (ERD) exists between dominant and non-dominant shoulders of cricketers as demonstrated in other overhead sports, and, if present, to establish if differences exist between cricketers with and without a history of gradual onset non-specific shoulder pain.DesignAn observational study.SettingNon-clinical, at national cricket indoor training venues.ParticipantsOne hundred and nine elite male and female cricketers (11–35 years), representing 97% of the England and Wales national and West of England regional Under 13 teams, consented. The final number included for data analysis was 133.Main outcome measuresData relating to playing position, cricket exposure, shoulder pain and demographic details collected using a questionnaire. Passive isolated glenohumeral rotation measured in 90° shoulder abduction using an inclinometer.ResultsCricketers who regularly bowl or throw overarm had significantly less internal (−7.9°, p<0.001) and greater external (8.6°, p<0.001) dominant to non-dominant glenohumeral rotation. Wicket-keepers had tendencies for smaller differences that were still statistically significant [mean IRD −5.9° (p<0.001); ERD 5.0° (p=0.002)]. Cricketers who experienced shoulder pain demonstrated a significantly greater IRD [mean 3.2° (p=0.032)] than those who did not.ConclusionsThe results of this study support measurement of passive glenohumeral joint rotation during musculoskeletal profiling and indicate that a possible link between increased IRD and non-specific shoulder pain warrants further investigation.     

Influence of thoracic posture on scapulothoracic and glenohumeral motions during eccentric shoulder external rotation

BackgroundThrowing injuries to the shoulder joint often occur during shoulder external rotation. An appropriate combination of thoracic, scapular, and humeral motion during throwing is important to prevent such injuries, but it is unclear how thoracic posture contributes to shoulder motion during throwing.Research questionThe purpose of this study, therefore, was to clarify the influence of thoracic posture on scapulothoracic and glenohumeral motion during shoulder external rotation.MethodsEccentric external rotation at 90° of shoulder abduction in thoracic flexion and extension postures was performed by 15 asymptomatic participants. Three-dimensional scapulothoracic and glenohumeral movements were measured with an electromagnetic tracking device at 75°, 80°, 85°, and maximum shoulder external rotation. The thoracic angle and maximum shoulder external rotation in absolute coordination were measured with a three-dimensional motion capture system.ResultsThe results showed that scapular posterior tilting and external rotation in the thoracic extension posture were significantly greater than those in the flexion posture (p < 0.05). Glenohumeral horizontal extension was significantly less in the thoracic extension posture than in the flexion posture (p < 0.05), whereas maximum shoulder external rotation was significantly greater (p < 0.01). Thus, thoracic extension increased scapulothoracic posterior tilting and external rotation and reduced glenohumeral horizontal extension during shoulder external rotation, as well as increasing maximum shoulder external rotation.SignificanceThese findings suggest that thoracic extension may contribute to reduction of mechanical demand in the glenohumeral joint during throwing, potentially reducing shoulder injuries.     

Shoulder position sense in volleyball players with infraspinatus atrophy secondary to suprascapular nerve neuropathy

Isolated infraspinatus atrophy (IIA ) is a common condition among overhead‐activity athletes, which affects the hitting shoulder and is caused by suprascapular nerve injury. As the suprascapular nerve is a mixed nerve, such damage could lead to reduced afferent proprioceptive information and impaired shoulder sensorimotor control. This study aimed to evaluate the proprioception of the shoulder with IIA , through the assessment of shoulder position sense. The shoulder position sense was assessed in 24 professional volleyball players (12 players with IIA and 12 healthy players) with a blind dynamic shoulder repositioning test (all participants were blindfolded during the test). Three functional glenohumeral movements were tested as follows: abduction, forward flexion, and a combination of abduction and external rotation. In all three tested movements, the affected shoulder of players with isolated infraspinatus atrophy showed significantly higher hand position error than the healthy contralateral (P <10⁻³, for all movements) and the healthy control group hitting shoulder (P <10⁻³, for abduction and flexion; P =.02, for combined movement of abduction and external rotation). The study highlights a reduced sense of position of the hitting shoulder in professional volleyball players with IIA secondary to suprascapular nerve palsy. The higher hand position error of the pathologic shoulder suggests an impairment of the shoulder sensorimotor control system, which likely results from reduced afferent proprioceptive information. Deficient afferent proprioceptive information may result in poor accuracy in descending motor commands and impairment of the shoulder neuromuscular function, leading to reduced shoulder functional stability and increased risk of injury.     

The gait profile score characterises walking performance impairments in young stroke survivors

BackgroundThe Gait Profile Score (GPS) provides a composite measure of the quality of joint movement during walking, but the relationship between this measure and metabolic cost, temporal (e.g. walking speed) and spatial (e.g. stride length) parameters in stroke survivors has not been reported.Research Question: The aims of this study were to compare the GPS (paretic, non-paretic, and overall score) of young stroke survivors to the healthy able-bodied control and determine the relationship between the GPS and metabolic cost, temporal (walking speed, stance time asymmetry) and spatial (stride length, stride width, step length asymmetry) parameters in young stroke survivors to understand whether the quality of walking affects walking performance in stroke survivors.MethodsThirty-nine young stroke survivors aged between 18 and 65years and 15 healthy age-matched able-bodied controls were recruited from six hospital sites in Wales, UK. Joint range of motion at the pelvis, hip, knee and ankle, and temporal and spatial parameters were measured during walking on level ground at self-selected speed with calculation of the Gait Variable Score and then the GPS.ResultsGPS for the paretic leg (9.40° (8.60–10.21) p < 0.001), non-paretic leg (11.42° (10.20–12.63) p < 0.001) and overall score (11.18° (10.26–12.09) p < 0.001)) for stroke survivors were significantly higher than the control (4.25° (3.40–5.10), 5.92° (5.11 (6.73)). All parameters with the exception of step length symmetry ratio correlated moderate to highly with the GPS for the paretic, non-paretic, and/or overall score (ρ = <−0.732 (p < 0.001)).SignificanceThe quality of joint movement during walking measured via the GPS is directly related to the speed and efficiency of walking, temporal (stance time symmetry) and spatial (stride length, stride width) parameters in young stroke survivors.     

Developing reliable measures of the passive torque-angle relationship for shoulder internal and external rotation: Implications for overhead athletics

Objectives1) Thoroughly assess shoulder flexibility by establishing the passive torque-angle relationship for internal and external rotation with the arm in an overhead athletics position (abducted 90°) and 2) test the reliability of four passive torque-angle measures.DesignReliability study.SettingData were collected in a university biomechanics laboratory.ParticipantsBilateral shoulder flexibility of 15 male college students (20.7 ± 1.1 y) was evaluated twice in two sessions over 7–10 days.Main outcome measuresFor both ER and IR, reliability was assessed bilaterally (intra-session, inter-session, and inter-tester) for the traditional range of motion measure and three novel kinetic measures: torque at end ROM, resistance onset angle, rotational stiffness. This resulted in 48 total assessments.ResultsThirty-four assessments had good to excellent reliability (ICC ≥ 0.8), 10 had fair reliability (0.7 ≤ ICC < 0.8), and 4 had poor reliability (ICC< 0.7). Three of the four flexibility measures had a good overall ICC score: ROM (0.83), torque at end ROM (0.84), and resistance onset angle (0.81). The fourth, stiffness, had a fair overall reliability score (0.74).ConclusionsThe passive torque-angle measures should be assimilated into clinical and research settings to determine the relevance to injury, rehabilitation, and performance.     

Normative reference values for handgrip strength,shoulder and ankle range of motion and upper-limb and lower limb stability for 137 youth judokas of both sexes

ObjectivesTo provide reference values for handgrip strength, shoulder and ankle range of motion (ROM) and upper-limb and lower limb stability for youth judokas of both sexes and investigate the effects of sex and side dominance.DesignCross-sectional.MethodsA total of 137 youth judokas from under-18 (n = 60) and under-21 (n = 77) categories of both sexes were assessed. Handgrip strength was assessed using a Jamar dynamometer, ankle ROM was measured by lunge test, shoulder ROM was assessed by an inclinometer and upper-limb and lower limb stability were assessed by the Closed Kinetic Chain Upper Extremity Stability Test and by the Modified Star Excursion Balance Test (mSEBT).ResultsIn both categories, males had greater handgrip strength. In the under-18 category, the dominant side had greater handgrip strength, the non-dominant side of females had smaller shoulder external rotation ROM than the dominant side and also than both sides of males, and females had greater shoulder IR ROM. In the under-21 category, the dominant side of females had greater ankle dorsiflexion ROM than the dominant side of males, the dominant sides and females had greater shoulder ER ROM, and males had better performance in the mSEBT.ConclusionsThis study provided reference values for handgrip strength, shoulder and ankle ROM, upper and lower limb stability for youth judokas, which can be used to guide assessment during preseason. Sex influenced on shoulder ER and IR ROM, handgrip strength and lower limb stability. In addition, side dominance influenced on shoulder ER ROM and on handgrip strength.     

The 45-second anterior knee pain provocation test: A quick test of knee pain and sporting function in 10–14-year-old adolescents with patellofemoral pain

ObjectiveTo test 1) if the 45-second Anterior Knee Pain Provocation Test (AKPP-test) could differentiate between adolescents with patellofemoral pain (PFP) and pain-free controls and; 2) whether improvements in the AKPP-test over 12 weeks were associated with improvements in self-reported knee function and pain.DesignProspective cohort.Patients151 with PFP and 50 pain-free controls (age 10–14 years).OutcomesThe AKPP-test was performed at baseline, 4- and 12-week follow-up. Pain and function were collected using Knee Injury and Osteoarthritis Outcome Score (KOOS).ResultsAt baseline, the AKPP-test provoked pain to a median of 5 points (IQR: 3–7) on the 0–10 Numeric Pain Rating Scale in adolescents with PFP, compared to 0 (IQR 0-0) in controls. Higher pain during the AKPP-test was associated with worse KOOS-Sport/Rec (r = −0.33, P < 0.001), worse KOOS-Pain (r = −0.47, P < 0.001), and pain intensity (worst pain last 24 hours) (r = −0.39, P < 0.001) at baseline. Improvements in the AKPP-test over 12 weeks were associated with improvements in KOOS Pain (r = 0.48, P < 0.001) and KOOS Sport/Rec (r = 0.40, P < 0.001).ConclusionsImprovements in the AKPP-test were associated with improvements in self-report knee pain and limitations in sports, suggesting the AKPP-test may be a clinically responsive test of knee pain and sporting function in adolescents with PFP.     

Stretching position can affect levator scapular muscle activity,length, and cervical range of motion in people with a shortened levator scapulae

ObjectivesLevator scapulae (LS) muscle stretching exercises are a common method of lengthening a shortened muscle; however, the appropriate stretching position for lengthening the LS in people with a shortened LS remains unclear. The purpose of this study was to compare the effects of different stretching exercise positions on the LS and introduce effective stretching exercise methods to clinicians.ParticipantsTwenty-four university students (12 men, 12 women) with a shortened LS were recruited.MethodsLS muscle activity, LS index (LSI), and cervical range of motion (ROM) were measured pre (baseline) and post three different stretching exercise positions (sitting, quadruped, and prone).ResultsThe LSI and cervical ROM exceeded the minimal detectable change and had significant changes. The LSI was greater in the sitting position than at the baseline (p = 0.01), quadruped position (p < 0.01); the LSI in the prone position presented a higher increase than the quadruped position (p = 0.01). The cervical ROM increased in the sitting position when compared to the baseline (p < 0.01) and quadruped position (p < 0.01).ConclusionsStretching the LS in the sitting position was the most effective exercise for improving LS muscle length and cervical ROM.     

The relationship between joint range of motion,muscular strength,and race time for sub-elite flat water kayakers

Upper body strength and flexibility are common training activities in elite flat water kayaking yet the relationship between joint range of motion, muscular strength, and race time is unclear. The aim of this research was to firstly quantify the flexibility and strength of sub-elite kayakers and then determine the relationship of this data to performance race times. Twenty-nine national standard kayak paddlers were assessed for shoulder and pelvic flexibility, upper body strength, and performance time. The shoulder internal and external rotation range of movement for kayak paddlers was reduced in comparison to other populations. For the female paddlers significant (p < 0.01) and strong correlations (r > 0.70) were found between shoulder flexion range of movement, shoulder strength, and strength endurance. Strength scores for kayak paddlers are reported for the first time showing the Pull:Push strength ratio for male kayak paddlers was 129%, and for females 147%. The strength ratio was significantly different (p < 0.01) across gender and also different to published ratios from other sports. Several other measures were also significantly different across gender. All paddlers showed significant and strong correlations between the three 8RM shoulder strength exercises, highlighting the importance of maintaining balance of strength for the muscles acting on the shoulder. There was only one measure, the strength endurance Bench-Pull-Max-Power for females that significantly and strongly correlated to the on-water performances; identifying the poor relationship between current dry land training activities and race performance. No single strength or ROM measure correlated strongly with on-water performances for either sex, as a sport kayaking appears to reduce the ROM about the shoulder joint.