***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 purpose of this study was to investigate the effect of concurrent strength and endurance training on strength , endurance , endocrine status and muscle fibre properties . A total of 45 male and female subjects were r and omly assigned to one of four groups ; strength training only ( S ) , endurance training only ( E ) , concurrent strength and endurance training ( SE ) , or a control group ( C ) . Groups S and E trained 3 days a week and the SE group trained 6 days a week for 12 weeks . Tests were made before and after 6 and 12 weeks of training . There was a similar increase in maximal oxygen consumption ( V˙O2max ) in both groups E and SE ( P < 0.05 ) . Leg press and knee extension one repetition maximum ( 1 RM ) was increased in groups S and SE ( P < 0.05 ) but the gains in knee extension 1 RM were greater for group S compared to all other groups ( P < 0.05 ) . Types I and II muscle fibre area increased after 6 and 12 weeks of strength training and after 12 weeks of combined training in type II fibres only ( P < 0.05 ) . Groups SE and E had an increase in succinate dehydrogenase activity and group E had a decrease in adenosine triphosphatase after 12 weeks of training ( P < 0.05 ) . A significant increase in capillary per fibre ratio was noted after 12 weeks of training in group SE . No changes were observed in testosterone , human growth hormone or sex hormone binding globulin concentrations for any group but there was a greater urinary cortisol concentration in the women of group SE and decrease in the men of group E after 12 weeks of training ( P < 0.05 ) . These findings would support the contention that combined strength and endurance training can suppress some of the adaptations to strength training and augment some aspects of capillarization in skeletal muscle Purpose To compare the increases in upper- and lower-body muscle strength in premenopausal women performing resistance training ( RT ) alone or alongside concurrent high-intensity interval training ( CT ) .  Methods Sixteen women ( 26–40 years ) were r and omly assigned into two groups that performed either RT or CT . Both groups performed the same RT program ; however , CT performed additional high-intensity interval training ( HIIT ) on a bicycle ergometer before RT . The study lasted 8 weeks and the participants were tested for ten repetition maximum ( 10RM ) load in elbow flexion ( barbell biceps curl ) and knee extension exercises pre- and post-intervention . RT was performed with 10–12 repetitions to self-determined repetition maximum in the first four weeks and then progressed to 8–10 . During CT , HIIT was performed before RT with six 1-min bouts at 7–8 of perceived subjective exertion ( RPE ) and then progressed to eight bouts at 9–10 RPE . Results Analysis of variance revealed significant increases in upper and lower body strength for both the RT and CT  groups . Biceps barbell curl 10RM load increased from 12.9 ± 3.2 kg to 14 ± 1.5 kg in CT ( p < 0.05 ) and from 13 ± 1.8 kg to 15.9 ± 2.5 kg in RT ( p < 0.05 ) , with no significant between-groups differences . Knee extension 10RM increase from 31.9 ± 11.6 kg to 37.5 ± 8.5 kg for CT ( p < 0.05 ) and from 30.6 ± 8.6 kg to 41.2 ± 7.4 kg for RT ( p < 0.05 ) . Conclusion In conclusion , performing HIIT on a cycle ergometer before resistance training does not seem to impair muscle strength increases in the knee extensors or elbow flexors of pre-menopausal women . This information should be considered when prescribing exercise sessions , since both activities may be combined without negative effects in muscle strength Resistance exercise and amino acids are two major factors that influence muscle protein turnover . Here , we examined the effects of resistance exercise and branched-chain amino acids ( BCAA ) , individually and in combination , on the expression of anabolic and catabolic genes in human skeletal muscle . Seven subjects performed two sessions of unilateral leg press exercise with r and omized supplementation with BCAA or flavored water . Biopsies were collected from the vastus lateralis muscle of both the resting and exercising legs before and repeatedly after exercise to determine levels of mRNA , protein phosphorylation , and amino acid concentrations . Intake of BCAA reduced ( P < 0.05 ) MAFbx mRNA by 30 and 50 % in the resting and exercising legs , respectively . The level of MuRF-1 mRNA was elevated ( P < 0.05 ) in the exercising leg two- and threefold under the placebo and BCAA conditions , respectively , whereas MuRF-1 total protein increased by 20 % ( P < 0.05 ) only in the placebo condition . Phosphorylation of p70(S6k ) increased to a larger extent ( ∼2-fold ; P < 0.05 ) in the early recovery period with BCAA supplementation , whereas the expression of genes regulating mTOR activity was not influenced by BCAA . Muscle levels of phenylalanine and tyrosine were reduced ( 13 - 17 % ) throughout recovery ( P < 0.05 ) in the placebo condition and to a greater extent ( 32 - 43 % ; P < 0.05 ) following BCAA supplementation in both resting and exercising muscle . In conclusion , BCAA ingestion reduced MAFbx mRNA and prevented the exercise-induced increase in MuRF-1 total protein in both resting and exercising leg . Further-more , resistance exercise differently influenced MAFbx and MuRF-1 mRNA expression , suggesting both common and divergent regulation of these two ubiquitin ligases Combining endurance and strength training in the same session has been reported to reduce the anabolic response to the latter form of exercise . The underlying mechanism , based primarily on results from rodent muscle , is proposed to involve AMPK-dependent inhibition of mTORC1 signaling . This hypothesis was tested in eight trained male subjects who in r and omized order performed either resistance exercise only ( R ) or interval cycling followed by resistance exercise ( ER ) . Biopsies taken from the vastus lateralis before and after endurance exercise and repeatedly after resistance exercise were assessed for glycogen content , kinase activity , protein phosphorylation , and gene expression . Mixed muscle fractional synthetic rate was measured at rest and during 3 h of recovery using the stable isotope technique . In ER , AMPK activity was elevated immediately after both endurance and resistance exercise ( ∼90 % , P < 0.05 ) but was unchanged in R. Thr(389 ) phosphorylation of S6K1 was increased severalfold immediately after exercise ( P < 0.05 ) in both trials and increased further throughout recovery . After 90 and 180 min recovery , S6K1 activity was elevated ( ∼55 and ∼110 % , respectively , P < 0.05 ) and eukaryotic elongation factor 2 phosphorylation was reduced ( ∼55 % , P < 0.05 ) with no difference between trials . In contrast , markers for protein catabolism were differently influenced by the two modes of exercise ; ER induced a significant increase in gene and protein expression of MuRF1 ( P < 0.05 ) , which was not observed following R exercise only . In conclusion , cycling-induced elevation in AMPK activity does not inhibit mTOR complex 1 signaling after subsequent resistance exercise but may instead interfere with the hypertrophic response by influencing key components in protein breakdown & NA ; Dupont , G. , K. Akakpo , and S. Berthoin . The effect of in‐season , high‐intensity interval training in soccer players . J. Strength Cond . Res . 18(3):584–589 . 2004.—The effects of inseason , high‐intensity interval training on professional male soccer players ’ running performances were investigated . Twentytwo subjects participated in 2 consecutive training periods of 10 weeks . The first period was considered a control period and was compared with a period where 2 high‐intensity interval training exercises were included in the usual training program . Intermittent runs consisted of 12–15 runs lasting 15 seconds at 120 % of maximal aerobic speed alternated with 15 seconds of rest . Sprint repetitions consisted of 12–15 all‐out 40‐m runs alternated with 30 seconds of rest . Results from the high‐intensity interval training have shown that maximal aerobic speed was improved ( + 8.1 ± 3.1 % ; p < 0.001 ) and that the time of the 40‐m sprint was decreased ( ‐3.5 ± 1.5 % ; p < 0.001 ) , whereas no change in either parameters were observed during the control period . This study shows that improvements in physical qualities can be made during the in‐season period Reports concerning the effect of endurance exercise on the anabolic response to strength training have been contradictory . This study re-investigated this issue , focusing on training effects on indicators of protein synthesis and degradation . Two groups of male subjects performed 7 weeks of resistance exercise alone ( R ; n = 7 ) or in combination with preceding endurance exercise , including both continuous and interval cycling ( ER ; n = 9 ) .  Muscle biopsies were taken before and after the training period . Similar increases in leg-press 1 repetition maximum ( 30 % ; P<0.05 ) were observed in both groups , whereas maximal oxygen uptake was elevated ( 8 % ; P<0.05 ) only in the ER group . The ER training enlarged the areas of both type I and type II fibers , whereas the R protocol increased only the type II fibers . The mean fiber area increased by 28 % ( P<0.05 ) in the ER group , whereas no significant increase was observed in the R group . Moreover , expression of Akt and mTOR protein was enhanced in the ER group , whereas only the level of mTOR was elevated following R training . Training-induced alterations in the levels of both Akt and mTOR protein were correlated to changes in type I fiber area ( r = 0.55–0.61 , P<0.05 ) , as well as mean fiber area ( r = 0.55–0.61 , P<0.05 ) , reflecting the important role played by these proteins in connection with muscle hypertrophy . Both training regimes reduced the level of MAFbx protein ( P<0.05 ) and tended to elevate that of MuRF-1 . The present findings indicate that the larger hypertrophy observed in the ER group is due more to pronounced stimulation of anabolic rather than inhibition of catabolic processes PURPOSE To assess the impact of 2 high-intensity interval-training ( HIT ) programs ( short interval vs sprint interval training ) on muscle strength and aerobic performances in a concurrent training program in amateur rugby sevens players . METHODS Thirty-six amateur rugby sevens players were r and omly assigned to strength and short interval training ( INT ) , strength and sprint interval training ( SIT ) , or a strength-only training group ( CON ) during an 8-wk period . Maximal strength and power tests , aerobic measurements ( peak oxygen uptake [ VO2peak ] and maximal aerobic velocity ) , and a specific repeated-sprint ability ( RSA ) test were conducted before and immediately after the overall training period . RESULTS From magnitude-based inference and effect size ( ES ± 90 % confidence limit ) analyses , the current study revealed substantial gains in maximal strength and jump-height performance in all groups . The difference in change of slow concentric torque production was greater in CON than in SIT ( 0.65 ± 0.72 , moderate ) . VO2peak and , consequently , mean performance in the RSA test were improved in the SIT group only ( 0.64 ± 0.29 , moderate ; -0.54 ± 0.35 , moderate ) . CONCLUSIONS The study did not emphasize interference on strength development after INT but showed a slight impairment of slow concentric torque production gains after SIT . Compared with INT , SIT would appear to be more effective to develop VO2peak and RSA but could induce lower muscle-strength gains , especially at low velocity 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 
    Output:
    
Compared to RT alone , concurrent HIIT and RT led to similar changes in muscle hypertrophy and upper body strength .
Data suggests concurrent HIIT and RT does not negatively impact hypertrophy or upper body strength , and that any possible negative effect on lower body strength may be ameliorated by incorporating running based HIIT and longer inter-modal rest periods