***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: The purpose of the present study was to examine the effects of active warm-up duration on the diurnal fluctuations in anaerobic performances . Twelve physical education students performed a medical stress test ( progressive test up to exhaustion ) and four Wingate tests ( measurement of peak power [ Ppeak ] , mean power [ Pmean ] , and fatigue index during an all-out 30 s cycling exercise ) . The tests were performed in separate sessions ( minimum interval = 36 h ) in a balanced and r and omized design at 08:00 and 18:00 h , either after a 5 min ( 5-AWU ) or a 15 min active warm-up ( 15-AWU ) . AWU consisted of pedaling at 50 % of the power output at the last stage of the stress exhausting test . Rectal temperature was collected throughout the sessions . A two-way ANOVA ( warm-up × time of day ) revealed a significant interaction for Ppeak ( F(1.11 ) = 6.48 , p < 0.05 ) and Pmean ( F(1.11 ) = 5.84 , p < 0.05 ) : the time-of-day effect was significant ( p < 0.001 ) in contrast with the effect of warm-up duration ( p > 0.05 ) . Ppeak and Pmean improved significantly from morning to afternoon after both 5-AWU and 15-AWU , but the effect of warm-up duration was significant in the morning only . Indeed , the values of Ppeak or Pmean were the same after both warm-up protocol s in the afternoon . For rectal temperature , there was no interaction between time-of-day and warm-up duration . Rectal temperature before and after both the warm-up protocol s was higher in the afternoon , and the effect of warm-up duration on temperature was similar at 08:00 and 18:00 h. In conclusion , the interpretation of the results of the anaerobic performance tests should take into account time-of-day and warm-up procedures . Longer warm-up protocol s are recommended in the morning to minimize the diurnal fluctuations of anaerobic performances . ( Author correspondence : n_souissi@yahoo.fr This investigation was conducted to determine the effect of high- and low-intensity warm-ups on physiological responses , lactate accumulation , and high-intensity freestyle and tethered swimming performance .  Ten male collegiate swimmers were tested for maximal oxygen uptake ( VO2 max ) followed by two series of three warm-up protocol s performed in a r and omized order at least 2 days apart . The warm-up protocol s were : ( 1 ) no warm-up ( NWU ) , ( 2 ) a 366-m swim at 70 % VO2 max ( LWU ) and ( 3 ) four 46-m swims at 1-min intervals at a speed corresponding to 110 % VO2 max ( HWU ) . Five minutes after each warm-up in the first series , the swimmers swam a 183-m st and ardized freestyle swim at a velocity corresponding to 110 % VO2 max , and 5 min after each warm-up in the second series the swimmers completed a tethered swim to exhaustion with a weight attached to the tether to elicit fatigue at about 2 min . Three minutes after each warm-up and 3 min after each st and ardized and tethered swim , a finger-prick blood sample for lactate measurement was obtained . Heart rate and VO2 were also measured during the warm-up and the st and ardized and tethered swims . The performance times in the tethered swim were not significantly different between the three conditions ( 116.8 + /- 46.8 , 137 + /- 53.3 and 122.94 + /- 37.2 s for the NWU , LWU and HWU , respectively ) . ( ABSTRACT TRUNCATED AT 250 WORDS The purpose of this study was to determine the effect of different static and dynamic stretch protocol s on 20-m sprint performance . The 97 male rugby union players were assigned r and omly to 4 groups : passive static stretch ( PSS ; n = 28 ) , active dynamic stretch ( ADS ; n = 22 ) , active static stretch ( ASST ; n = 24 ) , and static dynamic stretch ( SDS ; n = 23 ) . All groups performed a st and ard 10-minute jog warm-up , followed by two 20-m sprints . The 20-m sprints were then repeated after subjects had performed different stretch protocol s. The PSS and ASST groups had a significant increase in sprint time ( p ≤ 0.05 ) , while the ADS group had a significant decrease in sprint time ( p ≤ 0.05 ) . The decrease in sprint time , observed in the SDS group , was found to be nonsignificant ( p ≥ 0.05 ) . The decrease in performance for the 2 static stretch groups was attributed to an increase in the musculotendinous unit ( MTU ) compliance , leading to a decrease in the MTU ability to store elastic energy in its eccentric phase . The reason why the ADS group improved performance is less clear , but could be linked to the rehearsal of specific movement patterns , which may help increase coordination of subsequent movement . It was concluded that static stretching as part of a warm-up may decrease short sprint performance , whereas active dynamic stretching seems to increase 20-m sprint performance PURPOSE The purpose of the present study was to determine the effect of three different warm-up regimes on cycling work output during a 7-min performance trial . METHODS After habituation to the experimental methods , 12 well-trained cyclists completed a series of 7-min performance trials , involving 2 min of constant-work rate exercise at approximately 90 % VO2max and a further 5 min during which subjects attempted to maximize power output . This trial was performed without prior intervention and 10 min after bouts of moderate , heavy , or sprint exercise in a r and om order . Pulmonary gas exchange was measured breath by breath during all performance trials . RESULTS At the onset of the performance trial , baseline blood [ lactate ] was significantly elevated after heavy and sprint but not moderate exercise ( mean + /- SD : control , 1.0 + /- 0.3 mM ; moderate , 1.0 + /- 0.2 mM ; heavy , 3.0 + /- 1.1 mM ; sprint , 5.9 + /- 1.5 mM ) . All three interventions significantly increased the amplitude of the primary VO2 response ( control , 2.59 + /- 0.28 L x min(-1 ) ; moderate , 2.69 + /- 0.27 L x min(-1 ) ; heavy , 2.78 + /- 0.26 L x min(-1 ) ; sprint , 2.78 + /- 0.30 L x min(-1 ) ) . Mean power output was significantly increased by prior moderate and heavy exercise but not significantly reduced after sprint exercise ( control , 330 + /- 42 W ; moderate , 338 + /- 39 W ; heavy , 339 + /- 42 W ; sprint , 324 + /- 45 W ) . CONCLUSIONS These data indicate that priming exercise performed in the moderate- and heavy-intensity domains can improve severe-intensity cycling performance by ~2 - 3 % , the latter condition doing so despite a mild lactacidosis being present at exercise onset Warm-up and stretching are widely used as techniques in preparation for intense physical activity , yet there is little information available to compare their effectiveness in relation to athletic performance . Fourteen elite Under-19 year old rugby league footballers undertook each of four preparation protocol s ( no preparation , stretching only , warm-up only , warm-up and stretching ) in four successive testing sessions . Protocol s were r and omly allocated to players in a counterbalanced design so that each type of preparation occurred equally on each day of testing . During each session , athletes performed three solo sprint trials at maximum speed . Sprints were of 40-m distance and were electronically timed with wind speed and direction recorded . Preparation involving warm-up result ed in significantly faster sprint times compared to preparations having no warm-up , with a diminishing effect over the three trials . On the first trial , warm-up result ed in a mean advantage of 0.97 m over 40 m. Stretching result ed in a mean disadvantage of 0.18 m on the first trial , and no significant effect overall despite significant wind assistance . Warm-up was effective at improving immediate sprint performance , whereas an equivalent duration of lower limb stretching had no effect Curry , BS , Chengkalath , D , Crouch , GJ , Romance , M , and Manns , PJ . Acute effects of dynamic stretching , static stretching and light aerobic activity on muscular performance in women . J Strength Cond Res 23(6 ) : 1811 - 1819 , 2009-The purpose of this study was to compare three warm-up protocol s-static stretching , dynamic stretching , and light aerobic activity-on selected measures of range of motion and power in untrained females and to investigate the sustained effects at 5 and 30 minutes after warm-up . A total of 24 healthy females ( ages 23 - 29 years ) attended one familiarization session and three test sessions on nonconsecutive days within 2 weeks . A within-subject design protocol with the testing investigators blinded to the subjects ' warm-up was followed . Each session started with 5 minutes of light aerobic cycling followed by pretest baseline measures . Another 5 minutes of light aerobic cycling was completed and followed by one of the three r and omly selected warm-up interventions ( static stretching , dynamic stretching , or light aerobic activity ) . The following posttest outcome measures were collected 5 and 30 minutes following the intervention : modified Thomas test , countermovement jump , and isometric time to peak force knee extension measured by dynamometer . Analysis of the data revealed significant time effects on range of motion and countermovement jump changes . No significant differences ( p > 0.05 ) were found between the warm-up conditions on any of the variables . The variation in responses to warm-up conditions emphasizes the unique nature of individual reactions to different warm-ups ; however , there was a tendency for warm-ups with an active component to have beneficial effects . The data suggests dynamic stretching has greater applicability to enhance performance on power outcomes compared to static stretching Herman , SL and Smith , DT . Four-week dynamic stretching warm-up intervention elicits longer term performance benefits . J Strength Cond Res 22 : 1286 - 1297 , 2008-The purpose of this study was to determine whether a dynamic-stretching warm-up ( DWU ) intervention performed daily over 4 weeks positively influenced power , speed , agility , endurance , flexibility , and strength performance measures in collegiate wrestlers when compared to a static-stretching warm-up ( SWU ) intervention .  Twenty-four male National Collegiate Athletic Association Division I wrestlers were r and omly assigned to complete either a 4-week treatment condition ( DWU ) ( n = 11 ) or an active control condition ( SWU ) ( n = 13 ) prior to their daily preseason practice s. Anthropometric and performance measures were conducted before and after the 4-week experimental period ( i.e. , DWU or SWU ) . Measures included peak torque of the quadriceps and hamstrings , medicine ball underh and throw , 300-yd shuttle , pull-ups , push-ups , sit-ups , broad jump , 600-m run , sit- and -reach test , and trunk extension test . Wrestlers completing the 4-week DWU intervention had several performance improvements , including increases in quadriceps peak torque ( 11 % ) , broad jump ( 4 % ) , underh and medicine ball throw ( 4 % ) , sit-ups ( 11 % ) , and push-ups ( 3 % ) . A decrease in the average time to completion of the 300-yd shuttle ( -2 % ) and the 600-m run ( -2.4 % ) was suggestive of enhanced muscular strength , endurance , agility , and anaerobic capacity in the DWU group . In contrast to the DWU intervention , there was no observed improvement in the SWU group for peak torque of the quadriceps , broad jump , 300-yd shuttle run , medicine ball underh and throw for distance , sit-ups , push-ups , or 600-m run , and decrements in some performance measures occurred . The findings suggest that incorporation of this specific 4-week DWU intervention into the daily preseason training regimen of wrestlers produced longer-term or sustained power , strength , muscular endurance , anaerobic capacity , and agility performance enhancements This study aim ed to examine whether athletes are able to self-select their optimal warm up and to propose a method ological approach in investigating the effects of warm up on performance . Nine male subjects underwent a free field warm up ( FWU )  at a self-selected intensity and duration during which heart rate ( HR ) and rectal temperature ( Tre ) were monitored . The intensity of this warm up was subsequently estimated from the HR obtained during an incremental test to determine maximal power ( Pmax ) . Performance ( cycle time to exhaustion at Pmax ) , HR and Tre , were then examined following either : NWU ( no warm up ) ; RWU ( reference warm up based on FWU ) ; RWU-10 ( warm up intensity diminished by 10 % compared to RWU ) ; and RWU+10 ( warm up intensity increased by 10 % compared to RWU ) . Results showed no significant difference in HR ( P = 0.37 ) and Tre increase ( P= 0.77 ) between FWU and RWU . Performance improvement after warm up conditions gave RWU ( 56 % ; ie , 5/9 subjects ) > RWU-10 ( 33 % ; ie , 3/9 ) > RWU+10 ( 11 % ; ie , 1/9 ) > NWU with significant differences between RW 
    Output:
    
Cardiovascular warm-ups increased sprint/running time , but dynamic stretching and dynamic warm-ups had the most positive outcome for the various exercise tests examined .
Systematic ally , static stretching had no beneficial or detrimental effect on exercise performance but did improve range of movement exercises .
CONCLUSIONS Selected warm-up exercise may increase PFT and possibly CFT scores .