Concentric Muscle Strength Research Articles

Achilles Tendon Open Repair Augmented With Distal Turndown Tendon Flap and Posterior Crural Fasciotomy.

The aim of the present study was to investigate the outcomes after open repair of Achilles tendon rupture augmented with a distal turndown gastrocnemius flap and deep posterior crural fasciotomy based on the modified Lindholm technique. Twenty-three patients with acute Achilles tendon injury underwent open end-to-end tendon repair augmented with a distal turndown gastrocnemius flap and deep posterior compartment fasciotomy. The concentric and eccentric muscle strength was measured using a functional squat system, and dynamic balance was assessed using the Y-balance test with anterior, posteromedial, and posterolateral reach distances. Jump performance was assessed using the vertical jump and 1-leg hop tests. All patients returned to their preinjury activity level, and their mean American Orthopaedic Foot and Ankle Society hindfoot scale score was 98.2±2.3 after surgery. No significant difference was found between the involved and uninvolved extremities in terms of concentric and eccentric muscle strength (p=.82 and p=.53, respectively). In addition, no significant differences were seen between legs in the vertical jump (p=.16), one-leg hop (p=.15), and balance (p>.05) tests. Open end-to-end repair of the Achilles tendon rupture with augmentation and fasciotomy of the deep posterior compartment healed without any major complications. Functional performance of the involved leg after recovery was similar to that of the uninvolved leg. The modified Lindholm surgical technique described in our report appears to be a useful intervention for acute Achilles tendon rupture.

Kinesio Taping does not improve the symptoms or function of older people with knee osteoarthritis: a randomised trial.

Does Kinesio Taping reduce pain and swelling, and increase muscle strength, function and knee-related health status in older people with knee osteoarthritis? Randomised, controlled trial with concealed allocation, intention-to-treat analysis and blinded assessment. Seventy-six older people with knee osteoarthritis. The experimental group received three simultaneous Kinesio Taping techniques to treat pain, strength and swelling. The control group received sham taping. All participants kept the taping on for 4 days. The outcomes were: concentric muscle strength of knee extensors and flexors, measured by isokinetic dynamometry with an angular velocity of 60 deg/second normalised for body mass [(Nm/kg) x 100 (%)]; pressure pain threshold via digital pressure algometry (kgf/cm(2)); lower-limb swelling via volumetry (l) and perimetry (cm); physical function via the Lysholm Knee Scoring Scale (0 = worst to 100=best); and knee-related health status via the Western Ontario and McMaster (WOMAC) osteoarthritis index (0=best to 96=worst). Outcomes were measured at Day 4 (end of the taping period) and Day 19 (follow-up) after the start of the treatment. At Day 4, there were no significant between-group differences for knee extensor muscle strength (MD -1%, 95% CI -7 to 5), knee flexor muscle strength (MD 2%, 95% CI -3 to 7), the pressure pain threshold at any measured point, volumetry (MD 0.05 L, 95% CI -0.01 to 0.11), perimetry at any measured point, Lysholm score (MD -4 points, 95% CI -9 to 2), or WOMAC score (MD -2 points, 95% CI -8 to 4). The lack of significant between-group difference was also seen at the follow-up assessment on Day 19. The Kinesio Taping techniques investigated in this study provided no beneficial effects for older people with knee osteoarthritis on any of the assessed outcomes. Brazilian Registry of Clinical Trials, RBR-36r3t5. [Wageck B, Nunes GS, Bohlen NB, Santos GM, de Noronha M (2016) Kinesio Taping does not improve the symptoms or function of older people with knee osteoarthritis: a randomised trial.Journal of Physiotherapy62: 153-158].

Relationships between the Fibromyalgia Impact Questionnaire, pain severity, psychological profile and Muscle Strength in Female Patients with Fibromyalgia

The aim of this study was to compare various performances between women with fibromyalgia (FM) and healthy female controls and to assess the relationship between muscular function, pain intensity, disease severity and psychological profile in the fibromyalgia. We included forty-six women divided into two groups: the first group included 21 fibromyalgia patients and the second group included 25 healthy controls. All subjects had an evaluation of the trunk and knee muscular strength in the dominant limb using an isokinetic dynamometer. This assessment involved a measurement of the maximal concentric isokinetic muscle strength of the knee flexors and extensors at both 60°/s and 180°/s angular velocity, and a measurement of the maximal concentric isokinetic muscle strength of the trunk flexors and extensors at 60 and 150°/s. Muscular resistance to fatigue is assessed when the subject has performed 30 chained concentric contractions of maximum intensity at an angular velocity of 180°/s. The measured parameters were the peak of torque and the cumulative work. We evaluated the pain intensity both at rest and during exercise using visual analogical scale, the psychological profile via HAD scale, and the disease severity using the fibromyalgia impact questionnaire (FIQ). The strength and endurance of knee and trunk muscles were lower in fibromyalgia. The difference between these groups was significant ( P < 0.05). The isokinetic trunk deficit predominated on the trunk extensors ( P < 0.001). Mean decrease were 34.5% ( P < 0.05) for trunk flexors, 70% ( P < 0.05) for the trunk extensors, 20% ( P < 0.05) for the knee flexors and extensors, and 75% ( P < 0.001) for fatigue resistance. There were no significant correlations between isokinetic parameters, FIQ, pain intensity and psychological profile. Muscular strength and endurance were decreased in both knee and trunk muscles in fibromyalgia patients. The relationship between muscular strength, psychological profile and disease severity is weak. This implies that separate evaluations and treatments for every single co-morbidity are imposed.

Factors Associated With Dynamic Balance in People With Knee Osteoarthritis

ObjectiveTo identify potential neuromuscular factors associated with dynamic balance in individuals with knee osteoarthritis (OA). DesignCross-sectional observational study; backward stepwise multiple linear regression was used to identify factors associated with dynamic balance in 2 statistical models. SettingUniversity clinical research laboratory. ParticipantsIndividuals aged ≥50 years (N=52) with osteoarthritic changes on radiograph participated. InterventionsNot applicable. Main Outcome MeasuresDynamic balance was assessed using the Community Balance and Mobility Scale (CB&M). Potentially modifiable neuromuscular factors associated with dynamic balance were measured, including the sum of concentric and eccentric lower-extremity muscle strength, 2 quadriceps-hamstrings muscle strength ratios, knee joint proprioception (joint position sense), anticipatory postural control velocity, and knee joint range of motion. ResultsThe first model for explaining variance in CB&M scores consisted of eccentric lower-extremity muscle strength and knee joint range of motion as factors. The model containing these 2 variables explained 50% of the variance in CB&M scores. The second model adjusted for descriptive variables, including age, body mass index, and knee pain, contained only the neuromuscular variables eccentric lower-extremity muscle strength, and explained 68% of the variance in CB&M scores. ConclusionsThese results suggest that muscle strength and, to a lesser extent, knee joint range of motion are important factors associated with dynamic balance as measured by the CB&M and should be considered in dynamic balance interventions.

The Effect of Glenohumeral Internal-Rotation Deficit on Functional Rotator-Strength Ratio in Adolescent Overhead Athletes.

Glenohumeral (GH) internal-rotation deficit (GIRD) and lower eccentric external-rotator (ER) to concentric internal-rotator (IR) strength (ER:IR) ratio have been documented as risk factors for shoulder injuries, but there is no information on whether GIRD has an adverse effect on ER:IR ratio in adolescent overhead athletes. The aim of this study was to investigate the effects of GIRD on functional ER:IR ratio of the adolescent overhead athletes. Cross-sectional study. University research laboratory. 52 adolescent overhead athletes. To determine GIRD, the range of GH IR and ER motion was measured with a digital inclinometer. An isokinetic dynamometer was used to assess eccentric and concentric IR and ER muscle strength of the dominant and nondominant shoulders. One-way ANCOVA where sport type was set as a covariate was used to analyze the difference between athletes with and without GIRD. After standardized examinations of all shoulders, the athletes were divided into 2 groups, shoulders with (n = 27) and without GIRD (n = 25). There was a significant difference between groups in functional ER:IR ratio (P < .001). Athletes with GIRD had lower ER:IR ratio (0.56) than athletes without GIRD (0.83). As GIRD has an adverse effect on functional ratio of the shoulder-rotator muscles, interventions for adolescent overhead athletes should include improving GH-rotation range of motion.

Acute effects of static stretching on peak and end-range hamstring-to-quadriceps functional ratios.

To evaluate if static stretching influences peak and end-range functional hamstring-to-quadriceps (H/Q) strength ratios in elite women athletes. Eleven healthy female athletes in an elite competitive level participated to the study. All the participants fulfilled the static stretching or non-stretching (control) intervention protocol in a randomized design on different days. Two static unassisted stretching exercises, one in standing and one in sitting position, were used to stretch both the hamstring and quadriceps muscles during these protocols. The total time for the static stretching was 6 ± 1 min. The isokinetic peak torque measurements for the hamstring and quadriceps muscles in eccentric and concentric modes and the calculations for the functional H/Q strength ratios at angular velocities of 60°/s and 180°/s were made before (pre) and after (post) the control or stretching intervention. The strength measurements and functional strength ratio calculations were based during the entire- and end-range of knee extension. The pre-test scores for quadriceps and hamstring peak torque and end range values were not significantly different between the groups (P > 0.05). Subsequently, although the control group did not exhibit significant changes in quadriceps and hamstring muscle strength (P > 0.05), static stretching decreased eccentric and concentric quadriceps muscle strength at both the 60°/s and 180°/s test speeds (P < 0.01). Similarly, static stretching also decreased eccentric and concentric hamstring muscle strength at both the 60°/s and 180°/s test speeds (P < 0.01). On the other hand, when the functional H/Q strength ratios were taken into consideration, the pre-intervention values were not significant different between the groups both during the entire and end range of knee extension (P > 0.05). Furthermore, the functional H/Q strength ratios exhibited no significant alterations during the entire and end ranges of knee extension both in the static stretching or the control intervention (P > 0.05). According to our results, static stretching routine does not influence functional H/Q ratio. Athletes can confidently perform static stretching during their warm-up routines.

Effects of hamstring-emphasized neuromuscular training on strength and sprinting mechanics in football players.

The objective of this study was to examine the effects of a neuromuscular training program combining eccentric hamstring muscle strength, plyometrics, and free/resisted sprinting exercises on knee extensor/flexor muscle strength, sprinting performance, and horizontal mechanical properties of sprint running in football (soccer) players. Sixty footballers were randomly assigned to an experimental group (EG) or a control group (CG). Twenty-seven players completed the EG and 24 players the CG. Both groups performed regular football training while the EG performed also a neuromuscular training during a 7-week period. The EG showed a small increases in concentric quadriceps strength (ES = 0.38/0.58), a moderate to large increase in concentric (ES = 0.70/0.74) and eccentric (ES = 0.66/0.87) hamstring strength, and a small improvement in 5-m sprint performance (ES = 0.32). By contrast, the CG presented lower magnitude changes in quadriceps (ES = 0.04/0.29) and hamstring (ES = 0.27/0.34) concentric muscle strength and no changes in hamstring eccentric muscle strength (ES = -0.02/0.11). Thus, in contrast to the CG (ES = -0.27/0.14), the EG showed an almost certain increase in the hamstring/quadriceps strength functional ratio (ES = 0.32/0.75). Moreover, the CG showed small magnitude impairments in sprinting performance (ES = -0.35/-0.11). Horizontal mechanical properties of sprint running remained typically unchanged in both groups. These results indicate that a neuromuscular training program can induce positive hamstring strength and maintain sprinting performance, which might help in preventing hamstring strains in football players.

Achilles Tendon Open Repair Augmented with Volar Turndown Tendon Flap and Deep Posterior Crural Fasciotomy

Objectives:The aim of the study was to investigate the outcomes after open repair of Achilles tendon rupture with augmented volar turndown gastrocnemius flap and deep posterior crural fasciotomy.Methods:Twenty-three (22male/1female) patients with acute Achilles tendon injury were operated. Open end to end repair and augmentation with a volar turndown gastrocnemius flap and fasciotomy of the deep posterior compartment was performed in each patient. Home physiotherapy program was instructed for each patient. Muscle strength, balance and jump performance were assessed.Results:All patients returned to their preinjury activity level and repairs healed without any major complication. One patient had serous drainage who did not require surgical intervention (4,3%). There was no significant difference between involved and uninvolved leg in terms of concentric and eccentric muscle strength (p=0.82 and p=0.53, respectively). In Y balance test, there was no significant difference between involved and uninvolved legs in anterior (p=0.06), posteromedial (p=0.97) and posterolateral (p=1.00). In addition, there were no significant differences between leg in vertical jump (p=0.16) and one leg hop (p=0.15) tests. AOFAS Hindfoot score was 98.6±2.3 (93-100).Conclusion:Open end to end repair of the Achilles tendon rupture with augmentation and fasciotomy of the deep posterior compartment healed without any major complication. Fasciotomy of the deep posterior compartment decreased the tension at the skin repair site while decompressing the supeficial compartment anteriorly. Additionally, the augmented bulky repair construct of the Achilles tendon cambered volarly through the deep posterior compartment and decreased irritation sense during and after tendon healing.

Functional Strength Ratio in Athletes with and Without Glenohumeral Internal Rotation Deficit (GIRD)

Objectives:Eccentric external rotator (ER) and concentric internal rotator (IR) strength is expressed as a functional strength ratio (ER:IR) for shoulder. The difference in functional strength ratio has been well documented in athletes, but no one compared the functional ratio in athletes with glenohumeral internal rotation deficit (GIRD). The aim of this study was to investigate the effects of GIRD on functional ER:IR strength ratio of the adolescent athletes.Methods:Fifty-three adolescent athletes (12-18 years) from basketball and volleyball teams participated in the study. All the athletes were filled a questionnaire to obtain demographic information and information about their sporting activity. To determine the GIRD, the range of glenohumeral internal rotation motion was measured with the use of a digital inclinometer. An isokinetic dynamometer was used for the assessment of eccentric and concentric muscle strength of the dominant and non-dominant shoulders. Student-t test was used to assess the difference on ER:IR strength ratio between groups.Results:After the clinical examination of all shoulders the athletes were divided into 2 different groups, which were shoulders with glenohumeral internal rotation deficit (Group 1, n=34) and shoulders without GIRD (Group 2, n=22). There was a significant difference among groups on functional ER: IR strength ratio (t=-2.172, p=0.034). The ratio was lower in shoulders with GIRD.Conclusion:GIRD has an adverse effect on functional shoulder ratio, which is one of the causes of shoulder injuries in adolescent athletes. Therefore, GIRD should be treated to prevent future injuries.

Anterior cruciate ligament injury after more than 20 years. II. Concentric and eccentric knee muscle strength

The long-term consequences on knee muscle strength some decades after rupture of the anterior cruciate ligament (ACL) are not established. The aims of our study were to examine peak torque more than 20 years after ACL injury and to compare their knee muscle strength to that of healthy controls. We tested 70 individuals with unilateral ACL injury 23 ± 2 years after injury, whereof 33 (21 men) were treated with physiotherapy in combination with ACL reconstruction (ACLR ) and 37 (23 men) with physiotherapy alone (ACLPT ). These were compared with 33 age- and gender-matched controls (21 men). A Kin-Com(®) dynamometer (90°/s) was used to measure peak torque in knee flexion and extension in both concentric and eccentric contractions. Knee extension peak torque, concentric and eccentric, was ∼10% lower for the injured leg compared with the non-injured leg for both ACLR (P < 0.001; P < 0.001) and ACLPT (P = 0.007; P = 0.002). The ACLPT group also showed reduced eccentric knee flexion torque of the injured leg (P = 0.008). The strength of the non-injured leg in both ACL groups was equal to that of controls. No difference was seen for those with no-or-low degree of knee osteoarthritis compared to those with moderate-to-high degree of osteoarthritis. ACL injury may lead to a persistent reduction of peak torque in the injured leg, which needs to be considered across the lifespan.

Targeted physiotherapy treatment for patellofemoral osteoarthritis: a randomised clinical trial

Targeted physiotherapy treatment for patellofemoral osteoarthritis: a randomised clinical trial

Minimizing Preoperative and Postoperative Limping in Patients After Total Hip Arthroplasty

The aim of this study was to test the hypothesis that hip muscle function (strength and endurance) improves after total hip arthroplasty and is important for minimizing limping gait. Fifty-two patients who underwent total hip arthroplasty were assessed before and 6 mos after receiving a unilateral total hip endoprosthesis (Adaptiva stem with a Harris-Galante acetabular component). Severity of limping was assessed using a 4-point ordinal scale. Pain was assessed using a standardized ordinal scale. Eccentric, concentric, and isometric muscle strength and endurance of the hip extensors, flexors, adductors, and abductors were measured using a dynamometer. Postoperative limping severity and pain were significantly lower and postoperative muscle strength and endurance were significantly higher than the preoperative values (P < 0.05). The association between impaired muscle strength and endurance and limping severity was stronger postoperatively than preoperatively. This association was stronger for the hip extensor and flexor muscles than for the hip adductor and abductor muscles. Pain level was not associated with postoperative limping severity. Hip extensor and flexor muscle strength and endurance seem to be relevant for minimizing postoperative limping in patients after total hip arthroplasty. Rehabilitation programs should include exercises aimed at improving hip extensor and flexor strength and endurance to improve gait function.

Effects of Fitness and Vibration Training on Muscle Quality: A 1-Year Postintervention Follow-Up in Older Men

ObjectiveTo evaluate the residual effects of fitness and whole-body vibration (WBV) training in older men 1 year after completion of the interventions. DesignA 1-year follow-up of a randomized controlled trial comparing the effects of 1 year of fitness training, including combined resistance and aerobic (R+A) training and WBV training, with a control (CON) group. SettingUniversity training center. ParticipantsAdult men (N=72) between 60 and 80 years of age. Response rate was 80%, 92%, and 90% in the R+A training (n=20), WBV training (n=23), and CON (n=29) groups, respectively. InterventionsThe intervention groups exercised 3 times weekly during 1 year. The R+A training group performed a standard training program, combining resistance exercises and aerobic training, following the American College of Sports Medicine guidelines. The WBV training group performed unloaded static and dynamic leg exercises on a vibration platform. The CON group did not participate in any training program. Main Outcome MeasuresMuscle volume, isometric and concentric muscle strength, muscle quality, and muscle power. ResultsBoth interventions had resulted in comparable increases in muscle quality characteristics. No significant changes had been found in the CON group. During the 1-year follow-up period, the R+A (−4.05%, P=.006) and WBV (−2.45%, P<.0001) training groups had lost most of their gains in muscle volume. However, isometric muscle strength was preserved in the R+A training group (+1.65%, P=.745), resulting in an increase in muscle quality (+7.97%, P=.034). In the WBV training group, muscle power decreased (−6.10%, P<.0001) but remained significantly higher than at baseline (P=.038). Except for a strong decrease in muscle power, no significant changes were found in the CON group. ConclusionsOne year of R+A and/or WBV training can equally reverse the adverse effects of aging on muscle quality in older men, but their residual impact after follow-up is different.

Association between shoulder proprioception and muscle strength in water polo players

This study aimed to investigate the association between shoulder proprioception and shoulder rotators strength in water polo players. Twenty male water polo players aged 20.2 ± 2.3y participated in the study. Shoulder proprioception was evaluated by assessing joint position sense (JPS) at 30 ◦ of external rotation and at 30 ◦ of internal rotation. Shoulder external and internal rotators concentric and eccentric muscle strength was evaluated isokinetically at 120 ◦ /s. JPS acuity at 30 ◦ of external rotation (4.7 (3.5 ◦ )) was similar to that observed at 30 ◦ of internal rotation (4.0 (5.3 ◦ )). The external/internal rotators strength ratio were 0.67 (0.23) and 0.66 (0.18), respectively for concentric and eccentric efforts while the dynamic control ratio was 0.69 (0.16). Negative and significant correlations were found between relative error at 30 ◦ of external rotation and concentric and eccentric external rotators PT:r = �0.445 and r = �0.483, respectively, and the eccentric strength ratio of the external to internal rotators (r = �0.505). In addition the dynamic control ratio was lower than the recommended values for overhead athletes, which may expose/predispose the players to shoulder injury.

Concentric hip muscle function and quadriceps-hamstring ratio in athletes with and without patellofemoral pain syndrome

Background: Patellofemoral pain syndrome (PFPS) is a commonly seen condition in athletes. Several potential contributing factors have been postulated. Although hip muscle strength has been suggested to play a major role, concentric hip muscle function in athletes with PFPS has not been formally investigated. Objectives: We aimed to compare the concentric hip muscle strength in athletes with PFPS with that of controls, and to derive a concentric knee extension-to-flexion (quadriceps: hamstring) ratio Subjects and Methods: University athletes with PFPS (n=25) and asymptomatic controls (n = 25) were studied. Concentric torque of the hip abductors, adductors, flexors and extensors along with concentric knee extensors and flexors torque were assessed. Participants rated their knee pain in the week before the study on a visual analog scale and a self-administered anterior knee pain scale (AKPS). Strength testing was performed at 60°/s. Results: Participants with PFPS exhibited much lower concentric hip abduction, adduction, flexion and extension peak torque compared to controls. The concentric hip abduction to adduction and extension to flexion ratios showed no difference. Quadriceps:hamstring ratio was higher for PFPS participants. Conclusion: We propose that concentric hip muscle strength is significantly affected in PFPS. Clinicians are urged to include concentric strengthening exercises for the hip along with quadriceps and hamstring muscles during the rehabilitation of athletes with PFPS.

Inter- and Intrarater Reliability of Isokinetic Thigh Muscle Strength Tests in Postmenopausal Women With Osteopenia

Eitzen I, Hakestad KA, Risberg MA. Inter- and intrarater reliability of isokinetic thigh muscle strength tests in postmenopausal women with osteopenia. ObjectiveTo evaluate inter- and intrarater reliability of isokinetic muscle strength measurements during knee extension and flexion in postmenopausal women with osteopenia. DesignReliability study assessing inter- and intrarater reliability. SettingGeneral community. ParticipantsA convenience sample of 27 postmenopausal women (mean age ± SD, 68.2±7.3y) with defined osteopenia from a bone mineral density T score of less than 1.5 and a wrist fracture within the last 2 years. InterventionsNot applicable. Main Outcome MeasuresIsokinetic concentric muscle strength during knee extension and flexion was measured for 2 test conditions: 5 repetitions at 60°/s, and 25 repetitions at 180°/s. Agreement between tests was evaluated with the intraclass correlation coefficient (ICC2,1). Mean difference between tests, standard error of measurement (SEM and SEM%), and smallest real difference (SRD and SRD%) were calculated with 95% confidence intervals. SRD% and SEM% are emphasized in the results to allow congruent comparisons between the different test conditions. ResultsICC2,1 reflected high agreement both for inter- and intrarater reliability, with most of the values .90 or greater. There were no significant differences between the left and the right leg at any of the 3 tests. Some differences were apparent between the test sessions, but these were not systematic. Agreements were overall higher for assessments during knee extension than knee flexion. The SEM% was between 3.5% and 10.2% for knee extension, and 7.0% and 17.7% for knee flexion. SRD% was suggested to be between 15% and 20% for knee extension, and 25% and 30% for knee flexion. ConclusionsIsokinetic assessments of thigh muscle strength in postmenopausal women with osteopenia are of high reliability, with a level of agreement comparable to the levels found in previous reliability studies concerning both the healthy elderly and elderly with different health conditions. The measurement errors are small to moderate. The established SRD% provides thresholds for whether observed changes in strength in this patient group represent true change, which allows evaluations of minimal clinical importance in future studies.

Isokinetic Measurement of a Concentric and Eccentric Strength of the Rotators in Throwing

The shoulder injury was resulted from muscle imbalance between acceleration and deceleration during the throwing. The agonist-antagonist muscle strength relationship for throwing was formerly described as functional ratios of eccentric external rotator to concentric internal rotator moments and eccentric internal rotator to concentric external rotator moments. The purpose of this study was to measure the ratio of concentric and eccentric strength of the shoulder rotators by isokinetic muscle performance in Korean throwing college athletes for descriptive data. On 10 dominant shoulders of asymptomatic throwing college athletes applying Cybex II isokinetic dynamometer, concentric and eccentric muscle strength of the rotators were measured at the speed of 90/s, 180/s, 240/s. Maximal torque ratio of the eccentric strength of the external rotator against the concentric strength of the internal rotator was 1.25, 1.13, 1.21 at the each speed. The functional external eccentric-to-internal concentric ratio was similar with previous published studies. There was no significant difference between each speed. Eccentric strength of the external rotator was higher than concentric strength of the internal rotator during internal and external rotation at all speeds. This functional assessment of strength testing that reflected the importance of eccentric external rotation strength for the dynamic shoulder joint stability during the throwing. Therefore, the increase of the eccentric strength of the external rotator would be helpful to prevent the shoulder injury and to treat for rehabilitation of injured shoulder.

Relationships Between Lower Limb Muscle Strength and Locomotor Capacity in Children and Adolescents with Cerebral Palsy Who Walk Independently

ABSTRACTThis study aimed to quantify relationships between lower limb muscle strength and locomotor capacity for children and adolescents with cerebral palsy (CP) to identify key muscle groups for strength training. Fifty 6- to 16-year-olds with CP (Gross Motor Function Classification System level I or II) participated. Isometric muscle strength of hip flexor and abductor, knee flexor and extensor, and ankle dorsiflexor muscles was measured using hand-held dynamometry. Ankle plantar flexor concentric muscle strength was assessed as the maximal number of unilateral heel rises. Locomotor capacity was evaluated by the 6-min walk test (6MWT), 10-meter Shuttle Run Test (10mSRT), and Timed Up and Down Stairs Test (TUDS). With control for age, sex, and height, hip flexor and ankle plantar flexor strength explained 47.8% of the variance in the 6MWT and 32.9% of variance in the TUDS and hip abductor isometric strength explained 43.5% of the variance in the 10mSRT. Avenues for future research include randomized controlled trials that specifically target hip flexor muscles, as this has not previously been done, and determining factors other than strength that are likely related to locomotor capacity of children and adolescents with CP.

Physical self‐concept and physical fitness in elderly individuals

This investigation examined the relations between physical self-concept and physical fitness (endurance, balance, muscle strength, muscle power) for gaining knowledge about the interrelationship between subjective ratings and objective fitness scores in the elderly in three steps: (1) detecting correlations and changes in time, (2) clarifying the influence of gender, and (3) of a skiing intervention lasting 12 weeks. Physical self-concept was assessed using a modified version of the Physical Self-Concepts (PSK) scales (Stiller et al., 2004) reflecting three first-order factors (endurance, strength, general sportiness) and one second-order factor (global fitness). Objective fitness scores were obtained by VO(2 max), counter movement jump, concentric muscle strength, and static balance. The results reveal that elderly individuals' global physical self and general sportiness are mainly linked to VO(2 max) and concentric muscle strength. Global physical self is predicted by VO(2 max) in females and by physical strength (concentric muscle strength) in males, indicating gender differences. Over time, correlations between subjective ratings and objective fitness scores become stronger in the sense of convergent validity in the skiing intervention group, whereas convergent and divergent validity cannot be supported by data of the control group. In sum, physical self-concept is an important factor in the context of physical intervention programs in the elderly.

ACL Research Retreat V

ACL Research Retreat V