***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The objective of the study was to evaluate the effectiveness of functional progressive resistance exercise ( PRE ) training on walking ability in children with cerebral palsy ( CP ) . Fifty-one ambulant children with spastic CP ( mean age 10 years 5 months , 29 boys ) were r and omized to an intervention ( n=26 ) or control group ( n=25 , receiving usual care ) . The intervention consisted of 12 weeks functional PRE circuit training , for 3 times a week . Main outcome measures were walking ability and participation . Secondary outcomes were muscle strength and anaerobic muscle power . Possible adverse outcomes were spasticity and passive range of motion ( ROM ) . Muscle strength increased significantly in the training group compared to the control group , but walking ability , participation and anaerobic muscle power did not change . Spasticity and ROM remained unchanged , except for a significant decrease in rectus femoris length in the intervention group . It is concluded that twelve weeks of functional PRE-training does not improve walking ability , despite improved muscle strength AIM The aim of this study was to investigate whether individualized resistance training improves the physical mobility of young people with cerebral palsy ( CP ) . METHOD Forty-eight participants with spastic diplegic CP ( 26 males , 22 females ; mean age 18y 1mo , SD 1y 11mo ) classified as level II or III on the Gross Motor Function Classification System were allocated r and omly to progressive resistance training or usual-care control . Resistance training was completed twice weekly for 12 weeks at a community gymnasium under the supervision of a physiotherapist . Exercises were based on instrumented gait analysis and targeted muscles contributing to walking difficulties . Outcomes at 12 weeks and 24 weeks included objective measures of mobility ( 6-min walk test , instrumented gait analysis , and Gross Motor Function Measure dimensions D and E ) , participant-rated measures of mobility ( Functional Mobility Scale and Functional Assessment Question naire ) , and muscle performance . RESULTS The strength of targeted muscles increased by 27 % ( 95 % CI 8 - 46 % ) compared with control group . There were no between-group differences in any objective measure of mobility at 12 weeks ( 6-min walk test : mean difference 0.1 m ; 95 % CI -21 to 21 m ) or at 24 weeks . Participant-rated mobility improved ( Functional Mobility Scale at 5 m : mean 0.6 units ; 95 % CI 0.1 - 1.1 units ; Functional Assessment Question naire : 0.8 units ; 95 % CI 0.1 - 1.6 units ) compared with control group at 12 weeks . INTERPRETATION Individualized progressive resistance training increased strength in adolescents and young adults with spastic diplegic CP . Despite participant-rated benefits , the increased strength did not result in objective improvements in mobility AIM The aim of the present study was to assess and compare the improvements of muscle strength and power induced by a 16-week resistive programme in a population of 16 older men aged 65 - 81 years . METHODS Training was performed three times per week at an intensity of 80 % of one repetition maximum ( 1RM ) and consisted of both calf raise and leg press exercises . Before- , during- and after-training , maximum isometric and isokinetic torques , maximum power , 1RM , muscle cross-sectional area ( CSA ) and electromyographic activity ( EMG ) of the plantar flexors ( PF ) and knee extensors ( KE )  were examined . RESULTS For the KE and PF , respectively , training result ed in a 29.9 + /- 4.4 % ( mean + /- SE ) and 21.6 + /- 5.4 % increase in 1RM ( P < 0.001 - 0.01 ) , a 19.4 + /- 4.3 and 12.4 + /- 4.7 % ( P < 0.001 - 0.05 ) increase in maximum isometric torque , and a 24.1 + /- 6.3 and 33.1 + /- 10.9 % ( P < 0.05 ) increase in maximum muscle power , calculated from torque-angular velocity curves . The large increase in torque and power was partly accounted by a significant increase in the CSA of the PF ( 5.0 + /- 0.7 % ) and KE ( 7.4 + /- 0.7 % ) , while no significant changes in integrated EMG activity of vastus lateralis and soleus muscles , and in extrapolated maximum shortening velocity were found . After training , a significant increase in torque/CSA ( 10.3 + /- 4 % , P < 0.05 ) was found for the KE but not for the PF . CONCLUSION Hence , hypertrophy can not alone justify the increase in torque , and other factors , such as an increase in individual fibre-specific tension ( in the case of KE ) , a decrease in antagonist muscles ' coactivation , an improved co-ordination and an increased neural drive of the other heads of quadriceps may have contributed to the increments in strength . The significant increase in muscle power seems particularly noteworthy with respect to daily activities involving the displacement of the body over time , namely , the generation of muscle power Abstract The aims of this study were to assess changes in muscle architecture , isometric and dynamic strength of the leg extensor muscles , result ing from dynamic resistance training , and the relationships between strength and muscle architecture variables . The participants ( n = 30 ) were r and omly assigned to one of two groups . The training group ( n = 16 ; age 21.8 ± 2.3 years , body mass 74.8 ± 9.2 kg , height 1.75 ± 0.08 m ) performed dynamic resistance training for 13 weeks . The control group ( n = 14 ; age 19.9 ± 1.5 years , body mass 74.0 ± 8.5 kg , height 1.76 ± 0.05 m )  did not perform any resistance training .  Maximal dynamic and isometric strength were tested in both groups , before and after the training period . The members of the training group used the free-weight squat lift ( 90 ° ) as their training exercise . The concentric phase of the squat was performed explosively . Skeletal muscle architecture of the vastus lateralis was visualized using ultrasonography . At the end of the study , significant increases in vastus lateralis muscle thickness ( + 6.9 % , P < 0.001 ) , fascicle length ( + 10.3 % , P < 0.05 ) , one-repetition maximum ( + 8.2 % , P < 0.05 ) , rate of force development ( + 23.8 % , P < 0.05 ) and average force produced in the first 500 ms ( + 11.7 % , P < 0.05 ) were seen only in the training group . Adaptations to the muscle architecture in the training group limited the loss of fibre force , and improved the capacity for developing higher velocities of contraction . The architectural changes in the training group were similar to those seen in studies where high-speed training was performed . In conclusion , dynamic resistance training with light loads leads to increases in muscle thickness and fascicle length , which might be related to a more efficient transmission of fibre force to the tendon BACKGROUND Fascicle length and fascicle excursion measurements in children with cerebral palsy have yielded inconsistent results . The purpose of this study was to measure in vivo passive fascicle lengths and fascicle excursions in the Medial Gastrocnemius muscle of children with cerebral palsy and typically developing controls . METHODS We measured 11 children with spastic cerebral palsy and 14 controls between the ages of 9 and 16years .  Ultrasound imaging was used to measure fascicle lengths while a dynamometer moved the ankle joint through the range of motion . A common range of motion for all subjects was used for analysis of fascicle excursion . FINDINGS Fascicle lengths in children with cerebral palsy were 43 % smaller than those for control subjects throughout the range of motion . The relative fascicle excursion was 92 % greater on average for the cerebral palsy compared to the control group children . The muscle excursion for the control group children was greater than for the cerebral palsy group children . INTERPRETATION Since the fascicles in children with spastic cerebral palsy are shorter , but they go through the same excursion as fascicles in typically developing children , sarcomeres within the medial gastrocnemius muscle must be working over a larger range of sarcomere lengths . Combined with findings of overstretched sarcomeres in spastic muscles reported in the literature , our results suggest that the increased passive forces and the weakness found in spastic muscles may be caused by a decrease in contractile filament overlap as sarcomeres are pulled to extreme lengths in children with cerebral palsy Background . Everyday activities for youth with cerebral palsy ( CP ) require muscle power , but the velocity component of muscle contraction is neglected with traditional strength training ( ST ) . Objective . To determine whether velocity training ( VT ) , which includes resistance training at increasingly higher velocities , would induce specific muscle adaptations not observed with ST . Methods . Sixteen ambulatory youth with CP were r and omized to VT or ST . Participants trained the knee extensors 3 times per week for 24 sessions on a Biodex dynamometer . At each session , 6 sets of 5 concentric repetitions were performed either at 30 deg/s ( ST group ) or progressively higher velocities from 30 deg/s to 120 deg/s ( VT group ) . Outcomes included muscle architecture , power , strength , walking speed , and functional walking performance . Results . A significant increase in rectus femoris fascicle length was observed after VT with a decrease after ST . Rectus femoris cross-sectional area increased in both groups . Both showed significant increases in isokinetic strength at all tested speeds ; however , peak velocity and power improved after VT only . Self-selected and fast walking speed and functional walking performance improved after VT only . Conclusions . Muscle architecture in CP is capable of adapting differentially to the training stimulus . VT was equally effective as traditional ST in improving isokinetic strength of the knee extensors but more effective in improving velocity of movement , muscle power , and walking performance . Differences may be partially attributed to specificity of training effects on muscle architecture , such as the increase in fascicle length after VT . Strengthening interventions involving higher velocity movements should be incorporated into clinical practice Background . To date , no reports have investigated neuromuscular electrical stimulation ( NMES ) to increase muscle force production of children with cerebral palsy ( CP ) using high-force contractions and low repetitions . Objective . The aims of this study were to determine if isometric NMES or volitional training in children with CP could increase muscle strength and walking speed and to examine the mechanisms that may contribute to increased force production . Methods . Eleven children with spastic diplegia were assigned to an NMES training group or to a volitional training group . Participants in the NMES group had electrodes implanted percutaneously to activate the quadriceps femoris and triceps surae muscles . The volitional group trained with maximal effort contractions . Both groups performed a 12-week isometric strength-training program .  Maximum voluntary isometric contraction ( MVIC ) force , voluntary muscle activation , quadriceps and triceps surae cross-sectional area ( CSA ) , and walking speed were measured pre- and post-strength training . Results . The NMEStrained group had greater increases in normalized force production for both the quadriceps femoris and triceps surae . Similarly , only the NMES group showed an increase in walking speed after training . Changes in voluntary muscle activation explained approximately 67 % and 37 % of the changes seen in the MVIC of the NMES and volitional groups , respectively . Quadriceps femoris maximum CSA increased significantly for the NMES group only . Conclusions . This study was the first to quantitatively show strength gains with the use of NMES in children with CP . These results support the need for future experimental studies that will examine the clinical effectiveness of NMES strength training OBJECTIVE : To test the feasibility of creating a valid and reliable checklist with the following features : appropriate for assessing both r and omised and non-r and omised studies ; provision of both an overall score for study quality and a profile of scores not only for the quality of reporting , internal validity ( bias and confounding ) and power , but also for external validity . DESIGN : A pilot version was first developed , based on epidemiological principles , review s , and existing checklists for r and omised studies . Face and content validity were assessed by three experienced review ers and reliability was determined using two raters assessing 10 r and omised and 10 non-r and omised studies . Using different raters , the checklist was revised and tested for internal consistency ( Kuder-Richardson 20 ) , test-retest and inter-rater reliability ( Spearman correlation coefficient and sign rank test ; kappa statistics ) , criterion validity , and respondent burden . MAIN RESULTS : The performance of the checklist improved considerably after revision of a pilot version . The Quality Index had high internal consistency ( KR-20 : 0.89 ) as did the subscales apart from external validity ( KR-20 : 0.54 ) . Test-retest ( r 0.88 ) and inter-rater ( r 0.75 ) reliability of the Quality Index were good . Reliability of the subscales varied from good ( bias ) to poor ( external validity ) . The Quality Index correlated highly with an existing , established instrument for assessing r and omised studies ( r 0.90 ) . There was little difference between its performance with non-r and omised and with r and omised studies . Raters took about 20 minutes to assess each paper ( range 10 to 45 minutes ) . CONCLUSIONS : This study has shown that it is feasible to develop a checklist that can be used to assess the method o 
    Output:
    
A large effect was found on muscle cross-sectional area following strength training , with small to moderate effects on muscle volume and thickness .
CONCLUSION AND IMPLICATION S There is preliminary evidence that strength training leads to hypertrophy in children and adolescents with CP .
A paucity of studies exist measuring morphological and architectural parameters following strength training in these individuals .