***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 The effect of altering the rest period on adaptations to high-repetition resistance training is not well known . Eighteen active females were matched according to leg strength and repeated-sprint ability and r and omly allocated to one of two groups . One group performed resistance training with 20-s rest intervals between sets , while the other group employed 80-s rest intervals between sets . Both groups performed the same total training volume and load . Each group trained 3 days a week for 5 weeks [ 15- to 20-repetition maximum ( RM ) , 2 – 5 sets ] . Repeated-sprint ability ( 5 × 6-s maximal cycle sprints ) , 3-RM leg press strength , and anthropometry were determined before and after each training programme . There was a greater improvement in repeated-sprint ability after training with 20-s rest intervals ( 12.5 % ) than after training with 80-s rest intervals ( 5.4 % ) ( P = 0.030 ) . In contrast , there were greater improvements in strength after training with 80-s rest intervals ( 45.9 % ) than after training with 20-s rest intervals ( 19.6 % ) ( P = 0.010 ) . There were no changes in anthropometry for either group following training . These results suggest that when training volume and load are matched , despite a smaller increase in strength , 5 weeks of training with short rest periods results in greater improvements in repeated-sprint ability than the same training with long rest periods The purpose of this study was to compare the ability of various body-composition assessment techniques to detect changes in soft tissue in older , weight-stable women ( 50 - 70 y of age ) completing a 1-y r and omized , controlled trial of progressive resistance training . The intervention group ( n = 20 ) performed high-intensity strength-training 2 d/wk with five different exercises ; the control group ( n = 19 ) was untreated .  Hydrostatic weighing , 24-h urinary creatinine , computed tomography of thigh sections , total body potassium , and tritium dilution techniques were used to measure increases in total fat-free mass ( FFM ) and the muscle and water components of FFM . A decrease in fat mass ( by hydrostatic weighing ) was seen in the strength-trained women compared with the control subjects ( P - 0.01 - 0.0001 ) . Anthropometry , bioelectric impedance , dual-energy X-ray absorptiometry , and total body nitrogen and carbon did not measure any significant change in soft tissue . The choice of a body-composition technique is important when design ing a study expected to affect soft tissue , because not all techniques available are precise enough to detect small changes Piirainen , JM , Tanskanen , M , Nissilä J , Kaarela , J , Väärälä , A , Sippola , N , and Linnamo , V. Effects of a heart rate-based recovery period on hormonal , neuromuscular , and aerobic performance responses during 7 weeks of  strength training in men . J Strength Cond Res 25(8 ) : 2265 - 2273 , 2011—The purpose of this study was to compare hormonal , neuromuscular , and aerobic performance changes between a constant 2-minute interset recovery time and an interset recovery time based on individual heart rate ( HR ) responses during a 7-week ( 3 sessions per week , 3 × 10 repetition maximum [ RM ] ) hypertrophic strength training period . The HR-dependent recovery time was determined with a Polar FT80 HR monitor , whereas the control groups used constant 2-minute periods between sets . From 24 male subjects who were divided in 2 equal groups , 21 completed the study ( FT80 , n = 12 ; CONTROL , n = 9 ) . Serum blood sample s analyzed for testosterone ( TES ) and cortisol ( COR ) were taken before and after the 7-week training period at rest . Concentric knee extension 1RM was measured before , after 4 weeks , and at the end of the training period . Concentric knee extension and knee flexion 10RM , central activation ratio ( CAR ) , and max&OV0312;o2 were measured before and after the training . Serum TES concentrations were significantly higher after the training period in FT80 ( p < 0.001 ) , whereas no significant changes were observed in the CONTROL . Serum COR and max&OV0312;o2 were unchanged in both groups . In FT80 ( p < 0.001 ) , the increase in 10RM was higher ( p < 0.05 ) than in CONTROL ( p < 0.001 ) . Central activation ratio increased in both groups , with the significant increase observed in FT80 ( p < 0.05 ) . The higher TES responses , 10RM , and CAR development in FT80 suggest that an HR-based recovery period system of the FT80 may be more efficient in this type of hypertrophic strength training ( 3 × 10RM ) . The protocol in this study may be considered as a metabolic training cycle that coaches and trainers can use within a longer periodized training program To examine endogenous anabolic hormone and growth factor responses to various  heavy resistance exercise protocol s ( HREPs ) , nine male subjects performed each of six r and omly assigned HREPs  , which consisted of identically ordered exercises carefully design ed to control for load [ 5 vs. 10 repetitions maximum ( RM ) ] , rest period length ( 1 vs. 3 min ) , and total work effects . Serum human growth hormone ( hGH ) , testosterone ( T ) , somatomedin-C ( SM-C ) , glucose , and whole blood lactate ( HLa ) concentrations were determined preexercise , midexercise ( i.e. , after 4 of 8 exercises ) , and at 0 , 5 , 15 , 30 , 60 , 90 , and 120 min postexercise . All HREPs produced significant ( P less than 0.05 ) temporal increases in serum T concentrations , although the magnitude and time point of occurrence above resting values varied across HREPs . No differences were observed for T when integrated areas under the curve ( AUCs ) were compared . Although not all HREPs produced increases in serum hGH , the highest responses were observed consequent to the H10/1 exercise protocol ( high total work , 1 min rest , 10-RM load ) for both temporal and time integrated ( AUC ) responses . The pattern of SM-C increases varied among HREPs and did not consistently follow hGH changes . Whereas temporal changes were observed , no integrated time ( AUC ) differences between exercise protocol s occurred . These data indicate that the release patterns ( temporal or time integrated ) observed are complex functions of the type of HREPs utilized and the physiological mechanisms involved with determining peripheral circulatory concentrations ( e.g. , clearance rates , transport , receptor binding ) . All HREPs may not affect muscle and connective tissue growth in the same manner because of possible differences in hormonal and growth factor release Purpose To determine if 8 weeks of periodized strength resistance training ( RT ) utilizing relatively short rest interval lengths ( RI ) in between sets ( SS ) would induce greater improvements in body composition and muscular performance , compared to the same RT program utilizing extended RI ( SL ) . Methods 22 male volunteers ( SS : n = 11 , 65.6 ± 3.4 years ; SL : n = 11 , 70.3 ± 4.9 years ) were assigned to one of two strength RT groups , following 4 weeks of periodized hypertrophic RT ( PHRT ) : strength RT with 60-s RI ( SS ) or strength RT with 4-min RI ( SL ) . Prior to r and omization , all 22 study participants trained 3 days/week , for 4 weeks , targeting hypertrophy ; from week 4 to week 12 , SS and SL followed the same periodized strength RT program for 8 weeks , with RI the only difference in their RT prescription . Results Following PHRT , all study participants experienced increases in lean body mass ( LBM ) ( p < 0.01 ) , upper and lower body strength ( p < 0.001 ) , and dynamic power ( p < 0.001 ) , as well as decreases in percentage body fat ( p < 0.05 ) . Across the 8-week strength RT phase , SS experienced significantly greater increases in LBM ( p = 0.001 ) , flat machine bench press 1-RM ( p < 0.001 ) , bilateral leg press 1-RM ( p < 0.001 ) , narrow/neutral grip lat pulldown ( p < 0.01 ) , and Margaria stair-climbing power ( p < 0.001 ) , compared to SL . Conclusions This study suggests 8 weeks of periodized high-intensity strength RT with shortened RI induces significantly greater enhancements in body composition , muscular performance , and functional performance , compared to the same RT prescription with extended RI , in older men . Applied professionals may optimize certain RT-induced adaptations , by incorporating shortened RI de Souza Jr , TP , Fleck , SJ , Simão , R , Dubas , JP , Pereira , B , de Brito Pacheco , EM , da Silva , AC , and de Oliveira , PR . Comparison between constant and decreasing rest intervals : influence on maximal strength and hypertrophy . J Strength Cond Res 24(7 ) : 1843 - 1850 , 2010-Most resistance training programs use constant rest period lengths between sets and exercises , but some programs use decreasing rest period lengths as training progresses . The aim of this study was to compare the effect on strength and hypertrophy of 8 weeks of resistance training using constant rest intervals ( CIs ) and decreasing rest intervals ( DIs ) between sets and exercises . Twenty young men recreationally trained in strength training were r and omly assigned to either a CI or DI training group . During the first 2 weeks of training , 3 sets of 10 - 12 repetition maximum ( RM ) with 2-minute rest intervals between sets and exercises were performed by both groups . During the next 6 weeks of training , the CI group trained using 2 minutes between sets and exercises ( 4 sets of 8 - 10RM ) , and the DI group trained with DIs ( 2 minutes decreasing to 30 seconds ) as the 6 weeks of training progressed ( 4 sets of 8 - 10RM ) . Total training volume of the bench press and squat were significantly lower for the DI compared to the CI group ( bench press 9.4 % , squat 13.9 % ) and weekly training volume of these same exercises was lower in the DI group from weeks 6 to 8 of training . Strength ( 1RM ) in the bench press and squat , knee extensor and flexor isokinetic measures of peak torque , and muscle cross-sectional area ( CSA ) using magnetic resonance imaging were assessed pretraining and posttraining . No significant differences ( p ≤ 0.05 ) were shown between the CI and DI training protocol s for CSA ( arm 13.8 vs. 14.5 % , thigh 16.6 vs. 16.3 % ) , 1RM ( bench press 28 vs. 37 % , squat 34 vs. 34 % ) , and isokinetic peak torque . In conclusion , the results indicate that a training protocol with DI is just as effective as a CI protocol over short training periods ( 6 weeks ) for increasing maximal strength and muscle CSA ; thus , either type of program can be used over a short training period to cause strength and hypertrophy Regular performance of  resistance exercise induces an increase in skeletal muscle mass , however , the molecular mechanisms underlying this effect are not yet fully understood . The purpose of the present investigation was to examine acute changes in molecular signalling in response to resistance exercise involving different training volumes . Eight untrained male subjects carried out one , three and five sets of 6 repetition maximum ( RM ) in leg press exercise in a r and om order . Muscle biopsies were taken from the vastus lateralis both prior to and 30 min after each training session and the effect on protein signalling was studied . Phosphorylation of Akt was not altered significantly after any of the training protocol s , whereas that of the mammalian target of rapamycin was enhanced to a similar extent by training at all three volumes . The phosphorylation of p70S6 kinase ( p70S6k ) was elevated threefold after 3 × 6 RM and sixfold after 5 × 6 RM , while the phosphorylation of S6 was increased 30- and 55-fold following the 3 × 6 RM and 5 × 6 RM exercises , respectively . Moreover , the level of the phosphorylated form of the gamma isoform of p38 MAPK was enhanced three to fourfold following each of the three protocol s , whereas phosphorylation of ERK1/2 was unchanged 30 min following exercise . These findings indicate that when exercise is performed in a fasted state , the increase in phosphorylation of signalling molecules such as p70S6k and the S6 ribosomal protein in human muscle depends on the exercise volume Abstract In its last position st and about strength training , the American College of Sports Medicine recommends a rest interval ( RI ) between sets ranging between 1 and 3 min , varying in accordance with the objective . However , there is no consensus regarding the optimal recovery between sets , and most studies have investigated fixed intervals . Therefore , the aim of this study was to analyse the effects of fixed versus self-suggested RI between sets in lower and upper body exercises performance . Twenty-seven healthy subjects ( 26 ± 1.5 ; 75 ± 15 kg ; 175 ± 12 cm ) were r and omly assigned into two groups : G1 : lower body exercises and G2 : upper body exercises . Squat and leg press 1 repetition maximum ( 1RM ) were tested for the G1 and bench press and bice 
    Output:
    
Current evidence indicates that both short and long inter-set rest intervals may be useful when training for achieving gains in muscle hypertrophy .
Novel findings involving trained participants using measures sensitive to detect changes in muscle hypertrophy suggest a possible advantage for the use of long rest intervals to elicit hypertrophic effects .