***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: Background . Previous research has shown that children can increase their muscular strength and muscular endurance as a result of regular participation in a progressive resistance training program . However , the most effective exercise prescription regarding the number of repetitions remains question able . Objective . To compare the effects of a low repetition – heavy load resistance training program and a high repetition – moderate load resistance training program on the development of muscular strength and muscular endurance in children . Design . Prospect i ve , controlled trial . Setting . Community-based youth fitness center . Subjects . Eleven girls and 32 boys between the ages of 5.2 and 11.8 years . Intervention . In twice-weekly sessions of resistance training for 8 weeks , children performed 1 set of 6 to 8 repetitions with a heavy load ( n = 15 ) or 1 set of 13 to 15 repetitions with a moderate load ( n = 16 ) on child-size exercise machines . Children in the control group ( n = 12 ) did not resistance train . One repetition maximum ( RM ) strength and muscular endurance ( repetitions performed posttraining with the pretraining 1-RM load ) were determined on the leg extension and chest press exercises . Results . One RM leg extension strength significantly increased in both exercise groups compared with that in the control subjects . Increases of 31.0 % and 40.9 % , respectively , for the low repetition – heavy load and high repetition – moderate load groups were observed . Leg extension muscular endurance significantly increased in both exercise groups compared with that in the control subjects , although gains result ing from high repetition – moderate load training ( 13.1 ± 6.2 repetitions ) were significantly greater than those result ing from low repetition – heavy load training ( 8.7 ± 2.9 repetitions ) . On the chest press exercise , only the high repetition – moderate load exercise group made gains in 1-RM strength ( 16.3 % ) and muscular endurance ( 5.2 ± 3.6 repetitions ) that were significantly greater than gains in the control subjects . Conclusion . These findings support the concept that muscular strength and muscular endurance can be improved during the childhood years and favor the prescription of higher repetition – moderate load resistance training programs during the initial adaptation period AIM The aim of this study was to compare the effects of plyometric training versus basketball technique training on improving neuro-muscular performance . METHODS Thirty-six ( age 14.9±0.9 years , body height 164.0±7.6 cm , body weight 54.0±8.7 kg , BMI 20.1±2.4 kg·m-2 ) basketball players girls were r and omly allocated to 2 groups : Basketball Plyometric Training ( BPT  , N.=18 ) and Basketball Technique Training ( BTT  , N.=18 ) . The players were tested by two specific tests : counter movement jump ( CMJ ) and squat jump ( SJ ) before and after 6 training weeks . RESULTS The jump height , as dependent variable , showed a different trend as an effect of the different training protocol s , in contrast with the current knowledge . Manova did not show significant interactions between the two groups for the height of jumps , while significant differences were found for interaction time × training ( P<0.05 ) and for main effect × time ( P<0.001 ) . After training , the BPT group increased significantly CMJ performance by 11.3 % ( P<0.05 ) , whereas the BTT group increased by 4.6 % . Likewise , the BPT group demonstrated a significant greater improvement of jump height than BTT group ( an increase of 15.4 % vs. 7.5 % , P<0.01 ; respectively ) . CONCLUSION These results suggest that both training protocol s proposed in this study improved vertical jump performance . However , a combination of the two protocol s , plyometric training and sport-specific-exercises , could be useful to optimize performance by an easy transition from controlled a-specific to sport-specific performance requirements . In conclusion , BPT is a safe and effective method of achieving a favourable neuro-muscular performance than BTT in female basketball players The aim of this study was to determine the effectiveness of two different resistance training programs on lower limb explosive and reactive strength in young female athletes . Fifty seven rhythmic gymnasts were r and omly assigned to unspecific resistance training with dumbbells ( 12 repetition maximum squats )  ( n = 19 ; age = 12.0 + /- 1.8 years ) or to specific resistance training with weighted belts ( 6 % of body mass ; n = 18 ; age = 11.9 + /- 1.0 years ) . Squat jump test , counter movement jump test , hopping test , flexibility of the hip , and anthropometric measures were assessed before and after six weeks training . The main result was that both unspecific resistance training and specific resistance training protocol s positively affected the jumping performance , with an increase of the lower limb explosive strength of 6 - 7 % , with no side effects . Counter movement jump flight time increased significantly ( p < 0.01 ) while hopping test ground contact time significantly decreased ( p < 0.01 ) . No significant differences were detected among groups for flexibility , body mass , calf and thigh circumferences . Therefore , six weeks of resistance training that integrates different elements of rhythmic gymnastics training enhance jumping ability in young female athletes Abstract Ramírez-Campillo , R , Gallardo , F , Henriquez-Olguín , C , Meylan , CMP , Martínez , C , Álvarez , C , Caniuqueo , A , Cadore , EL , and Izquierdo , M. Effect of vertical , horizontal , and combined plyometric training on explosive , balance , and endurance performance of young soccer players . J Strength Cond Res 29(7 ) : 1784–1795 , 2015—The aim of this study was to compare the effects of 6 weeks of vertical , horizontal , or combined vertical and horizontal plyometric training on muscle explosive , endurance , and balance performance .  Forty young soccer players aged between 10 and 14 years were r and omly divided into control ( CG ; n = 10 ) , vertical plyometric group ( VG ; n = 10 ) , horizontal plyometric group ( HG ; n = 10 ) , and combined vertical and horizontal plyometric group ( VHG ; n = 10 ) . Players performance in the vertical and horizontal countermovement jump with arms , 5 multiple bounds test ( MB5 ) , 20-cm drop jump reactive strength index ( RSI20 ) , maximal kicking velocity ( MKV ) , sprint , change of direction speed ( CODS ) , Yo-Yo intermittent recovery level 1 test ( Yo-Yo IR1 ) , and balance was measured . No significant or meaningful changes in the CG , apart from small change in the Yo-Yo IR1 , were observed while all training programs result ed in meaningful changes in explosive , endurance , and balance performance . However , only VHG showed a statistically significant ( p ⩽ 0.05 ) increase in all performance test and most meaningful training effect difference with the CG across tests . Although no significant differences in performance changes were observed between experimental groups , the VHG program was more effective compared with VG ( i.e. , jumps , MKV , sprint , CODS , and balance performance ) and HG ( i.e. , sprint , CODS , and balance performance ) to small effect . The study demonstrated that vertical , horizontal , and combined vertical and horizontal jumps induced meaningful improvement in explosive actions , balance , and intermittent endurance capacity . However , combining vertical and horizontal drills seems more advantageous to induce greater performance improvements Abstract Santos , EJAM and Janeira , MAAS . The effects of resistance training on explosive strength indicators in adolescent basketball players . J Strength Cond Res 26(10 ) : 2641–2647 , 2012—The purpose of this study was to assess the effects of a lower- and upper-body 10-week in-season resistance training program on explosive strength development in young basketball players . Twenty-five adolescent male athletes , aged 14–15 years old , were r and omly assigned to an experimental group ( EG ; n = 15 ) and a control group ( CG ; n = 10 ) . The subjects were assessed at baseline and after training for  squat jump ( SJ ) , countermovement jump ( CMJ ) , Abalakov test , drop jump , and seated medicine ball throw ( MBT ) . The EG showed significant increases ( p < 0.05 ) in all the variable scores . Conversely , the CG significantly decreased ( p < 0.05 ) in SJ , CMJ , and Abalakov test scores and significantly increased in the results of MBT test ( p < 0.05 ) . The groups were similar on pretest , but significant differences ( p < 0.05 ) occurred on posttest in all the variables . The results of this study show that a 10-week in-season resistance training program with moderate volume and intensity loads increased vertical jump and MBT performance in adolescent male basketball players . Coaches should know that such a short resistance training program specifically design ed for young basketball players induce increased explosivity levels , which are essential to a better basketball performance , with no extra overload on adolescents ' skeletal muscle development Abstract Ferrete , C , Requena , B , Suarez-Arrones , L , and Sáez de Villarreal , E. Effect of strength and high-intensity training on jumping , sprinting , and intermittent endurance performance in prepubertal soccer players . J Strength Cond Res 28(2 ) : 413–422 , 2014—The purpose of this study was to examine the effects of a 26-week on-field combined strength and high-intensity training on the physical performance capacity among prepubertal soccer players who were undertaking a competitive phase of training . Twenty-four prepubertal soccer players between the age of 8 and 9 years were r and omly assigned to 2 groups : a control ( C ; n = 13 ) and an experimental group ( S ; n = 11 ) . Both groups performed an identical soccer-training program , whereas the S group also performed combined strength and high-intensity training before the soccer-specific training . The 15-m sprint time ( seconds ) , countermovement jump ( CMJ ) displacement , Yo-Yo intermittent endurance test ( Yo-Yo IE ) , and Sit and Reach flexibility were each measured before ( baseline ) and after 9 ( T2 ) , 18 ( T3 ) , and 26 weeks ( posttest ) of training . There were no significant differences between the groups in any of the variables tested at baseline . After 26 weeks , significant improvements were found in the CMJ ( 6.72 % ; effect size [ ES ] = 0.37 ) , Yo-Yo IE ( 49.57 % , ES = 1.39 ) , and Flexibility ( 7.26 % ; ES = 0.37 ) variables for the S group . Conversely , significant decreases were noted for the CMJ ( −10.82 % ; ES = 0.61 ) and flexibility ( −13.09 % ; ES = 0.94 ) variables in the C group . A significant negative correlation was found between 15-m sprint time and CMJ ( r = −0.77 ) and Yo-Yo IE ( r = −0.77 ) in the S group . Specific combined strength and high-intensity training in prepubertal soccer players for 26 weeks produced a positive effect on performance qualities highly specific to soccer . Therefore , we propose modifications to current training methodology for prepubertal soccer players to include strength and high-intensity training for athlete preparation in this sport PURPOSE To analyze the effects of low-load , high-velocity resistance training ( RT ) combined with plyometrics on physical performance in pre-peak-height-velocity ( PHV ) soccer players . METHODS Thirty young soccer players from the same academy were r and omly assigned to either a strength training ( STG , n = 15 ) or a control group ( CG , n = 15 ) . Strength training consisted of full squat exercise with low load ( 45 - 58 % 1RM ) and low volume ( 4 - 8 repetitions/set ) combined with jumps and sprints twice a week over 6 wk of preseason . The effect of the training protocol was assessed using sprint performance over 10 and 20 m , countermovement jump , estimated 1-repetition maximum , and average velocity attained against all loads common to pre- and posttests in full squat . RESULTS STG showed significant improvements ( P = .004-.001 ) and moderate to very large st and ardized effects ( ES = 0.71 - 2.10 ) in all variables measured , whereas no significant gains were found in CG ( ES = -0.29 to 0.06 ) . Moreover , significant test × group interactions ( P < .003-.001 ) and greater between-groups ESs ( 0.90 - 1.97 ) were found for all variables in favor of STG compared with CG . CONCLUSION Only 6 wk of preseason low-volume and low-load RT combined with plyometrics can lead to relevant improvements in strength , jump , and sprint performance . Thus , the combination of field soccer training and lightweight strength training could be used for a greater development of the tasks critical to soccer performance in pre-PHV soccer players Abstract Radnor , JM , Lloyd , RS , and Oliver , JL . Individual response to different forms of resistance training in school-aged boys . J Strength Cond Res 31(3 ) : 787–797 , 2017—The aim of this study was to examine individual responses to different forms of resistance training on measures of jumping and sprinting performance in school-aged boys . Eighty boys were categorized into 2 maturity groups ( pre- or post – peak height velocity [ PHV ] ) and r and omly assigned to a plyometric training , resistance training , combined training , or control group . Intervention groups participated in training twice weekly for 6 weeks , with measures of acceleration , maximal running velocity , squat jump height , and reactive strength index ( RSI ) collected preintervention and postintervention . In the pre-PHV cohort , plyometric training and combined training result ed in significantly more positive responders than the other 
    Output:
    
The meta- analysis showed small to moderate magnitude changes for training specificity with jump measures .
In other words , power training was more effective than strength training for improving youth jump height .
For sprint measures , strength training was more effective than power training with youth .
Furthermore , strength training exhibited consistently large magnitude changes to lower body strength measures , which contrasted with the generally trivial , small and moderate magnitude training improvements of power training upon lower body strength , sprint and jump measures , respectively .
Maturity related inadequacies in eccentric strength and balance might influence the lack of training specificity with the unilateral l and ings and propulsions associated with sprinting .