***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: 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 Hammami , M , Negra , Y , Aouadi , R , Shephard , RJ , and Chelly , MS . Effects of an in-season plyometric training program on repeated change of direction and sprint performance in the junior soccer player . J Strength Cond Res 30(12 ) : 3312–3320 , 2016—We aim ed to determine the gains in explosive movements of male junior soccer players induced by incorporating an 8-week plyometric training program ( PTP ) into a st and ard soccer conditioning regimen 5 months after the beginning of the competitive season . Our hypothesis was that PTP would enhance explosive movements , and thus sprint running , repeated shuttle sprint ability ( RSSA ) , agility and the ability to make repeated changes of direction ( RCOD ) .  A group of junior soccer players were r and omly divided into 2 groups : an  experimental group ( E , n = 15 , age 15.7 ± 0.2 years ) and a  control group ( C , n = 13 , age 15.8 ± 0.2 years ) . The participants in E and C performed training exercises and matches together , but for an 8-week period in the latter part of the season , the experimental group replaced a part of the normal regimen ( the tactical session ) by a biweekly course of PTP ( hurdle and drop jumps ) . Two familiarization sessions were held 2 weeks before definitive testing . The ability of the players was assessed by 3 agility tests ( a sprint test with 180 ° turns , a 9 - 3 - 6 - 3 - 9 m sprint with backward and forward running , and a four 5-m sprint test with turns ) ; 2 repeated sprint tests ( RSSA and RCOD ) ; and running times over 5- , 10- , 20- , 30- , and 40-m distances . Participants in E showed gains relative to C in sprint times ( p ⩽ 0.05 for 5 , 10 , and 20 m ) , and 2 of 3 the RCOD parameters ( RCOD best , p ⩽ 0.001 ; RCOD total , p ⩽ 0.05 ) . However , with the pattern of plyometric training that we adopted , and perhaps because participants were in good initial physical condition , the agility and RSSA test scores remained unchanged . Nevertheless , we conclude that our PTP can be commended to junior soccer players as a means of improving important components of their physical performance Thomas , K , French , D , and Hayes , PR . The effect of two plyometric training techniques on muscular power and agility in youth soccer players . J Strength Cond Res 23(1 ) : 332 - 335 , 2009-The aim of this study was to compare the effects of two plyometric training techniques on power and agility in youth soccer players . Twelve males from a semiprofessional football club 's academy ( age = 17.3 ± 0.4 years , stature = 177.9 ± 5.1 cm , mass = 68.7 ± 5.6 kg ) were r and omly assigned to 6 weeks of depth jump ( DJ ) or countermovement jump ( CMJ ) training twice weekly . Participants in the DJ group performed drop jumps with instructions to minimize ground-contact time while maximizing height . Participants in the CMJ group performed jumps from a st and ing start position with instructions to gain maximum jump height . Posttraining , both groups experienced improvements in vertical jump height ( p < 0.05 ) and agility time ( p < 0.05 ) and no change in sprint performance ( p > 0.05 ) . There were no differences between the treatment groups ( p > 0.05 ) . The study concludes that both DJ and CMJ plyometrics are worthwhile training activities for improving power and agility in youth soccer players Meylan , C and Malatesta D. Effects of in-season plyometric training within soccer practice on explosive actions of young players . J Strength Cond Res 23(9 ) : 2605 - 2613 , 2009-In soccer , explosive actions such as jumping , sprinting , and changes of direction are essential to optimal performance not only in adults , but also in children 's games . The purpose of the present investigation was to determine the influence of a short-term plyometric training within regular soccer practice on explosive actions of early pubertal soccer players during the in-season . Fourteen children ( 13.3 ± 0.6 years ) were selected as the training group ( TG ) and 11 children ( 13.1 ± 0.6 years ) were defined as the control group ( CG ) . All children were playing in the same league and trained twice per week for 90 minutes with the same soccer drills . The TG followed an 8-week plyometric program ( i.e. , jumping , hurdling , bouncing , skipping , and footwork ) implemented as a substitute for some soccer drills to obtain the same session duration as CG . At baseline and after training , explosive actions were assessed with the following 6 tests : 10-meter sprint , agility test , 3 vertical jump tests ( squat jump [ SJ ] , countermovement jump [ CMJ ] , contact test [ CT ] and multiple 5 bounds test [ MB5 ] ) . Plyometric training was associated with significant decreases in 10-m sprint time ( −2.1 % ) and agility test time ( −9.6 % ) and significant increases in jump height for the CMJ ( + 7.9 % ) and CT ( + 10.9 % ) . No significant changes in explosive actions after the 8-week period were recorded for the CG . The current study demonstrated that a plyometric program within regular soccer practice improved explosive actions of young players compared to conventional soccer training only . Therefore , the short-term plyometric program had a beneficial impact on explosive actions , such as sprinting , change of direction , and jumping , which are important determinants of match-winning actions in soccer performance Abstract Sáez de Villarreal , E , Suarez-Arrones , L , Requena , B , Haff , GG , and Ferrete , C. Effects of plyometric and sprint training on physical and technical skill performance in adolescent soccer players . J Strength Cond Res 29(7 ) : 1894–1903 , 2015—To determine the influence of a short-term combined plyometric and sprint training ( 9 weeks ) within regular soccer practice on explosive and technical actions of pubertal soccer players during the in-season . Twenty-six players were r and omly assigned to 2 groups : control group ( CG ) ( soccer training only ) and combined group ( CombG ) ( plyometric + acceleration + dribbling + shooting ) . All players trained soccer 4 times per week and the experimental groups supplemented the soccer training with a proposed plyometric-sprint training program for 40 minutes ( 2 days per weeks ) . Ten-meter sprint , 10-m agility with and without ball , CMJ and Abalakov vertical jump , ball-shooting speed , and Yo-Yo intermittent endurance test were measured before and after training . The experimental group followed a 9-week plyometric and sprint program ( i.e. , jumping , hurdling , bouncing , skipping , and footwork ) implemented before the soccer training . Baseline-training results showed no significant differences between the groups in any of the variables tested . No improvement was found in the CG ; however , meaningful improvement was found in all variables in the experimental group : CMJ ( effect size [ ES ] = 0.9 ) , Abalakov vertical jump ( ES = 1.3 ) , 10-m sprint ( ES = 0.7–0.9 ) , 10-m agility ( ES = 0.8–1.2 ) , and ball-shooting speed ( ES = 0.7–0.8 ) . A specific combined plyometric and sprint training within regular soccer practice improved explosive actions compared with conventional soccer training only . Therefore , the short-term combined program had a beneficial impact on explosive actions , such as sprinting , change of direction , jumping , and ball-shooting speed which are important determinants of match-winning actions in soccer performance . Therefore , we propose modifications to current training methodology for pubertal soccer players to include combined plyometric and speed training for athlete preparation in this sport Abstract Campillo , RR , And rade , DC , and Izquierdo , M. Effects of plyometric training volume and training surface on explosive strength . J Strength Cond Res 27(10 ) : 2714–2722 , 2013—The purpose of this study is to examine the effects of different volume and training surfaces during a short-term plyometric training program on neuromuscular performance .  Twenty-nine subjects were r and omly assigned to 4 groups : control group ( CG , n = 5 ) , moderate volume group ( MVG , n = 9 , 780 jumps ) , moderate volume hard surface group ( MVGHS , n = 8 , 780 jumps ) , and high volume group ( HVG , n = 7 , 1,560 jumps ) . A series of tests were performed by the subjects before and after 7 weeks of plyometric training . These tests were measurement of maximum strength ( 5 maximum repetitions [ 5RMs ] ) , drop jumps ( DJs ) of varying heights ( 20 , 40 , and 60 cm ) , squat and countermovement jumps ( SJ and CMJ , respectively ) , timed 20-m sprint , agility , body weight , and height . The results of the present study suggest that high training volume leads to a significant increase in explosive performance that requires fast stretch-shortening cycle ( SSC ) actions ( such as DJ and sprint ) in comparison to what is observed after a moderate training volume regimen . Second , when plyometric training is performed on a hard training surface ( high-impact reaction force ) , a moderate training volume induces optimal stimulus to increase explosive performance requiring fast SSC actions ( e.g. , DJ ) , maximal dynamic strength enhancement , and higher training efficiency . Thus , a finding of interest in the study was that after 7 weeks of plyometric training , performance enhancement in maximal strength and in actions requiring fast SSC ( such as DJ and sprint ) were dependent on the volume of training and the surface on which it was performed . This must be taken into account when using plyometric training on different surfaces Abstract Ramírez-Campillo , R , Meylan , CMP , Álvarez-Lepín , C , Henriquez-Olguín , C , Martinez , C , And rade , DC , Castro-Sepúlveda , M , Burgos , C , Baez , EI , and Izquierdo , M. The effects of interday rest on adaptation to 6 weeks of plyometric training  in young soccer players . J Strength Cond Res 29(4 ) : 972–979 , 2015—The purpose of this study was to determine the effects of short-term plyometric training interposed with 24 or 48 hours of rest between training sessions on explosive and endurance adaptations in young soccer players . A total of 166 players , between 10 and 17 years of age , were r and omly divided into 3 groups : a control group ( CG ; n = 55 ) and 2 plyometric training groups with 24 hours ( PT24 ; n = 54 ) and 48 hours ( PT48 ; n = 57 ) of rest between training sessions . Before and after intervention , players were measured in squat jump , countermovement jump , 20 ( RSI20 ) cm drop jump reactive strength index , broad long jump , 20-m sprint time , 10 × 5-m agility time , 20-m multistage shuttle run test , and sit- and -reach test .  The plyometric training program was applied during 6 weeks , 2 sessions per week , with a load from 140 to 260 
    Output:
    
In conclusion , PT  improves COD ability in youths , with meaningfully greater effects in older youths .
Two PT sessions per week , with 1,400 moderate-intensity jumps for 7 weeks , seems to be an adequate dose