***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: Evidence -based practice involves the use of evidence from systematic review s and r and omised controlled trials , but the extent of this evidence in physiotherapy has not previously been surveyed . The aim of this survey is to describe the quantity and quality of r and omised controlled trials and the quantity of systematic review s relevant to physiotherapy . The Physiotherapy Evidence Data base ( PEDro ) was search ed . The quality of trials was assessed with the PEDro scale . The search identified a total of 2,376 r and omised controlled trials and 332 systematic review s. The first trial was published in 1955 and the first review was published in 1982 . Since that time , the number of trials and review s has grown exponentially . The mean PEDro quality score has increased from 2.8 in trials published between 1955 and 1959 to 5.0 for trials published between 1995 and 1999 . There is a substantial body of evidence about the effects of physiotherapy . However , there remains scope for improvements in the quality of the conduct and reporting of clinical trials We reported , using a unilateral resistance training ( RT ) model , that training with high or low loads ( mass per repetition ) result ed in similar muscle hypertrophy and strength improvements in RT-naïve subjects . Here we aim ed to determine whether the same was true in men with previous RT experience using a whole-body RT program and whether postexercise systemic hormone concentrations were related to changes in hypertrophy and strength . Forty-nine resistance-trained men ( 23 ± 1 yr , mean ± SE ) performed 12 wk of whole-body RT .  Subjects were r and omly allocated into a higher-repetition ( HR ) group who lifted loads of ∼30 - 50 % of their maximal strength ( 1RM ) for 20 - 25 repetitions/set ( n = 24 ) or a lower-repetition ( LR ) group ( ∼75 - 90 % 1RM , 8 - 12 repetitions/set , n = 25 ) , with all sets being performed to volitional failure . Skeletal muscle biopsies , strength testing , dual-energy X-ray absorptiometry scans , and acute changes in systemic hormone concentrations were examined pretraining and posttraining . In response to RT , 1RM strength increased for all exercises in both groups ( P < 0.01 ) , with only the change in bench press being significantly different between groups ( HR , 9 ± 1 , vs. LR , 14 ± 1 kg , P = 0.012 ) . Fat- and bone-free ( lean ) body mass and type I and type II muscle fiber cross-sectional area increased following training ( P < 0.01 ) with no significant differences between groups . No significant correlations between the acute postexercise rise in any purported anabolic hormone and the change in strength or hypertrophy were found . In congruence with our previous work , acute postexercise systemic hormonal rises are not related to or in any way indicative of RT-mediated gains in muscle mass or strength . Our data show that in resistance-trained individuals , load , when exercises are performed to volitional failure , does not dictate hypertrophy or , for the most part , strength gains & NA ; Physical therapists seeking to use evidence to guide their practice may have limited time to read research reports . One way to reduce the time required to identify and read about the research that is relevant to a particular clinical question is to read a systematic review that summarizes multiple studies . This paper explains the process that is used to conduct systematic review s , which includes the establishment of a protocol , comprehensive search ing , appraisal of the quality of the included studies , data extraction and meta analysis , and consideration of the clinical and research implication s of the findings . We also consider how the reader of a systematic review can determine whether the review is likely to provide an unbiased ( believable ) estimate of the treatment effect . A systematic review of r and omized trials of a  cardiopulmonary physical therapy intervention is used as an example . The issue of appraisal of quality is then discussed further , with a demonstration of how one vali date d tool for quality appraisal ‐‐the PEDro scale‐‐can be used to evaluate a r and omized trial in cardiopulmonary physical therapy We have reported that the acute postexercise increases in muscle protein synthesis rates , with differing nutritional support , are predictive of longer-term training-induced muscle hypertrophy . Here , we aim ed to test whether the same was true with acute exercise-mediated changes in muscle protein synthesis . Eighteen men ( 21 ± 1 yr , 22.6 ± 2.1 kg/m(2 ) ; means ± SE ) had their legs r and omly assigned to two of three training conditions that differed in contraction intensity [ % of maximal strength ( 1 repetition maximum ) ] or contraction volume ( 1 or 3 sets of repetitions ) : 30%-3 , 80%-1 , and 80%-3 . Subjects trained each leg with their assigned regime for a period of 10 wk , 3 times/wk . We made pre- and posttraining measures of strength , muscle volume by magnetic resonance ( MR ) scans , as well as pre- and posttraining biopsies of the vastus lateralis , and a single postexercise ( 1 h ) biopsy following the first bout of exercise , to measure signaling proteins . Training-induced increases in MR-measured muscle volume were significant ( P < 0.01 ) , with no difference between groups : 30%-3 = 6.8 ± 1.8 % , 80%-1 = 3.2 ± 0.8 % , and 80%-3= 7.2 ± 1.9 % , P = 0.18 . Isotonic maximal strength gains were not different between 80%-1 and 80%-3 , but were greater than 30%-3 ( P = 0.04 ) , whereas training-induced isometric strength gains were significant but not different between conditions ( P = 0.92 ) . Biopsies taken 1 h following the initial resistance exercise bout showed increased phosphorylation ( P < 0.05 ) of p70S6 K only in the 80%-1 and 80%-3 conditions . There was no correlation between phosphorylation of any signaling protein and hypertrophy . In accordance with our previous acute measurements of muscle protein synthetic rates a lower load lifted to failure result ed in similar hypertrophy as a heavy load lifted to failure Purpose To determine if muscle growth is important for increasing muscle strength or if changes in strength can be entirely explained from practicing the strength test . Methods Thirty-eight untrained individuals performed knee extension and chest press exercise  for 8 wk . Individuals were r and omly assigned to either a high-volume training group ( HYPER ) or a group just performing the one repetition maximum ( 1RM ) strength test ( TEST ) . The HYPER group performed four sets to volitional failure ( ~8RM–12RM ) , whereas the TEST group performed up to five attempts to lift as much weight as possible one time each visit . Results Data are presented as mean ( 90 % confidence interval ) . The change in muscle size was greater in the HYPER group for both the upper and lower bodies at most but not all sites . The change in 1RM strength for both the upper body ( difference of −1.1 [ −4.8 , 2.4 ] kg ) and lower body ( difference of 1.0 [ −0.7 , 2.8 ] kg for dominant leg ) was not different between groups ( similar for nondominant ) . Changes in isometric and isokinetic torque were not different between groups . The HYPER group observed a greater change in muscular endurance ( difference of 2 [ 1,4 ] repetitions ) only in the dominant leg . There were no differences in the change between groups in upper body endurance . There were between-group differences for exercise volume ( mean [ 95 % confidence interval ] ) of the dominant ( difference of 11,049.3 [ 9254.6–12,844.0 ] kg ) leg ( similar for nondominant ) and chest press with the HYPER group completing significantly more total volume ( difference of 13259.9 [ 9632.0–16,887.8 ] kg ) . Conclusions These findings suggest that neither exercise volume nor the change in muscle size from training contributed to greater strength gains compared with just practicing the test Background In this study , we investigated the effects of resistance training protocol s with different loads on muscle hypertrophy and strength . Methods Twenty-one participants were r and omly assigned to 1 of 3 ( n = 7 for each ) resistance training ( RT ) protocol s to failure : High load 80 % 1RM ( 8–12 repetitions ) ( H group ) , low load 30 % 1RM ( 30–40 repetitions ) ( L group ) and a mixed RT protocol ( M group ) in which the participants switch from H to L every 2 weeks . RT consisted of three sets of unilateral preacher curls performed with the left arm 3 times/week with 90 s rest intervals between sets . The right arm served as control . Maximum voluntary contraction ( MVC ) of the elbow flexors ( elbow angle : 90 ° ) and rate of force development ( RFD , 0–50 , 50–100 , 100–200 and 200–300 ms ) were measured . Cross-sectional area ( CSA ) of the elbow flexors was measured via magnetic resonance imaging ( MRI ) . All measurements were conducted before and after the 8 weeks of RT ( 72–96 h after the last RT ) . Statistical evaluations were performed with two-way repeated measures ( time × group ) . Results After 8 weeks of 3 weekly RT sessions , significant increases in the left elbow flexor CSA [ H : 9.1 ± 6.4 % ( p = 0.001 ) , L : 9.4 ± 5.3 % ( p = 0.001 ) , M : 8.8 ± 7.9 % ( p = 0.001 ) ] have been observed in each group , without significant differences between groups . Significant changes in elbow flexor isometric MVC have been observed in the H group ( 26.5 ± 27.0 % , p = 0.028 ) , while no significant changes have been observed in the M ( 11.8 ± 36.4 % , p = 0.26 ) and L ( 4.6 ± 23.9 % , p = 0.65 ) groups . RFD significantly increased during the 50–100 ms phase in the H group only ( p = 0.049 ) . Conclusions We conclude that , as long as RT is conducted to failure , training load might not affect muscle hypertrophy in young men . Nevertheless , strength and RFD changes seem to be load-dependent . Furthermore , a non-linear RT protocol switching loads every 2 weeks might not lead to superior muscle hypertrophy nor strength gains in comparison with straight RT protocol Abstract Schoenfeld , BJ , Peterson , MD , Ogborn , D , Contreras , B , and Sonmez , GT . Effects of low- vs. high-load resistance training on muscle strength and hypertrophy in well-trained men . J Strength Cond Res 29(10 ) : 2954–2963 , 2015—The purpose of this study was to compare the effect of low- versus high-load resistance training ( RT ) on muscular adaptations in well-trained subjects . Eighteen young men experienced in RT were matched according to baseline strength and then r and omly assigned to 1 of 2 experimental groups : a low-load RT routine ( LL ) where 25–35 repetitions were performed per set per exercise ( n = 9 ) or a high-load RT routine ( HL ) where 8–12 repetitions were performed per set per exercise ( n = 9 ) . During each session , subjects in both groups performed 3 sets of 7 different exercises representing all major muscles . Training was performed 3 times per week on nonconsecutive days , for a total of 8 weeks . Both HL and LL conditions produced significant increases in thickness of the elbow flexors ( 5.3 vs. 8.6 % , respectively ) , elbow extensors ( 6.0 vs. 5.2 % , respectively ) , and quadriceps femoris ( 9.3 vs. 9.5 % , respectively ) , with no significant differences noted between groups . Improvements in back squat strength were significantly greater for HL compared with LL ( 19.6 vs. 8.8 % , respectively ) , and there was a trend for greater increases in 1 repetition maximum ( 1RM ) bench press ( 6.5 vs. 2.0 % , respectively ) . Upper body muscle endurance ( assessed by the bench press at 50 % 1RM to failure ) improved to a greater extent in LL compared with HL ( 16.6 vs. −1.2 % , respectively ) . These findings indicate that both HL and LL training to failure can elicit significant increases in muscle hypertrophy among well-trained young men ; however , HL training is superior for maximizing strength adaptations Muscle adaptations can be induced by high-resistance exercise . Despite being potentially more suitable for older adults , low-resistance exercise protocol s have been less investigated . We compared the effects of high- and low-resistance training on muscle volume , muscle strength , and force-velocity characteristics . Fifty-six older adults were r and omly assigned to 12 weeks of leg press and leg extension training at either HIGH ( 2 × 10 - 15 repetitions at 80 % of one repetition maximum ( 1RM ) ) , LOW ( 1 × 80 - 100 repetitions at 20 % of 1RM ) , or LOW+ ( 1 × 60 repetitions at 20 % of 1RM , followed by 1 × 10 - 20 repetitions at 40 % of 1RM ) . All 
    Output:
    
Gains in 1RM strength were significantly greater in favor of high- vs. low-load training , whereas no significant differences were found for isometric strength between conditions .
Changes in measures of muscle hypertrophy were similar between conditions .
The findings indicate that maximal strength benefits are obtained from the use of heavy loads while muscle hypertrophy can be equally achieved across a spectrum of loading ranges