High-intensity Warm-up Research Articles

Effects of High-Intensity Warm-Up on 5000-Meter Performance Time in Trained Long-Distance Runners.

Warm-up protocols with high intensities before continuous running provide potential benefits for middle-distance runners. Nevertheless, the effect of high-intensity warm-ups on long-distance runners remains unclear. The purpose of this study was to verify the effect of a high-intensity warm-up protocol on 5000 m performance in trained runners. Thirteen male runners (34 ± 10 years, 62 ± 6 kg, 62.7 ± 5.5 ml/kg/min) performed two 5000 m time trials, preceded by two different warm-ups. One high-intensity warm up (HIWU: 1x 500 m (70% of the running intensity) + 3x 250 m (100% of the running intensity) and one low-intensity warm up (LIWU: 1x 500 m (70% of the running intensity) + 3x 250 m (70% of the running intensity)), where the running intensities were calculated using the results obtained in the Cooper test. Physiological and metabolic responses, and endurance running performance parameters, were evaluated by the Counter Movement Jump (CMJ), running rating of perceived exertion (RPE), blood lactate concentration (BLa), and performance running. Total time for the 5000 m was lower using HIWU when compared to LIWU (1141.4 ± 110.4 s vs. 1147.8 ± 111.0 s; p = 0.03; Hedges' g = 0.66). The HIWU warm-up led to an improvement in pacing strategy during the time trial. After warm-up protocols, the performance on the CMJ was improved only when applying HIWU (p = 0.008). Post warm-up BLa was significantly higher for HIWU vs. LIWU (3.5 ± 1.0 mmol·L-1 vs. 2.3 ± 1.0 mmol·L-1; p = 0.02), with similar behavior for the RPE (p = 0.002), internal load of the session (p = 0.03). The study showed that a high-intensity warm-up protocol can improve performance in the 5000 m in trained endurance runners.

Effects of an experimental short-time high-intensity warm-up on explosive muscle strength performance in soccer players: A pilot study.

Objective: This study aimed to evaluate the effects of an experimental short-time warm-up consisting of a small number of intermittent high-intensity sprints on explosive muscle strength performance in soccer players and to identify recovery times after performing the sprints. Furthermore, we evaluated the reliability of a smartphone app in jumping performance. Methods: Twenty male soccer players were given the following tests: 1) the counter-movement jump (CMJ) test with the Microgate system, 2) the counter-movement jump (CMJ) test with the MyJump smartphone app, and 3) the handgrip strength test. The experimental short-time high-intensity warm-up was carried out 1 week after test administration. The warm-up consisted of three maximum sprints over 60 m with 120 s of recovery between sprints. Then, the tests were administered again: the vertical jump height (VJH) performances (five trials) were measured 90 s after the last sprint; the handgrip strength performances (three trials) were measured 120 s after the last vertical jump test. Results: The maximum VJH was found in the third trial of the CMJ test, 330 s after the last sprint (p < 0.01), the result closest to the baseline. The lowest VJH was found in the first trial of the CMJ test, 90 s after the last sprint (p < 0.05). Pearson’s analysis between the CMJ test with the Microgate system and the CMJ test with MyJump showed a strong correlation (R = 0.96). Lin’s concordance correlation coefficient showed a substantial concordance (ρc = 0.959) between measures. Conclusion: This experimental short-time warm-up of high-intensity intermittent sprints appears to be a simple, quick, and efficient activity to accelerate soccer players’ optimal performance.

Warm-Up Intensity and Time-Course Effects on Jump Height under Cold Conditions.

With this study, we aimed to investigate the effects of different warm-up intensities on counter-movement jump (CMJ) performance over time under cold conditions. Eleven male collegiate athletes volunteered. The participants performed high-intensity warm-up (HWU) at 80% VO2max and moderate-intensity warm-up (MWU) at 60% VO2max for 15 min on a bicycle ergometer in a laboratory room at 10 °C. CMJ height, vastus lateralis muscle temperature, heart rate, and perceived fatigue were measured before warm-up (Pre), immediately after (Post 0), 10 min after (Post 10), and 20 min after (Post 20). Significant main effects and interactions were found for CMJ height (time, p < 0.001 and ηp2 = 0.859; interaction, p = 0.007 and ηp2 = 0.327). HWU significantly increased CMJ height at Post 0 to Post 20 compared to that at Pre (p < 0.01), whereas MWU increased CMJ height at Post 0 only compared to that at Pre (p < 0.001). The results indicate that HWU achieved an increase in CMJ height for 20 min. MWU changed CMJ height instantly, but the change did not last compared to HWU in a cold environment.

A High-Intensity Warm-Up Increases Thermal Strain But Does Not Affect Repeated Sprint Performance in Athletes With a Cervical Spinal Cord Injury.

To compare the effects of typical competition versus high-intensity intermittent warm-up (WU) on thermoregulatory responses and repeated sprint performance during wheelchair rugby game play. An intermittent sprint protocol (ISP) simulating the demands of wheelchair rugby was performed by male wheelchair rugby players (7 with cervical spinal cord injury [SCI] and 8 without SCI) following 2 WU protocols. These included a typical competition WU (control) and a WU consisting of high-intensity efforts (INT). Core temperature (Tcore), thermal sensation, and thermal comfort were recorded. Wheelchair performance variables associated to power, speed, and fatigue were also calculated. During the WU, Tcore was similar between conditions for both groups. During the ISP, a higher Tcore was found for SCI compared to NON-SCI (38.1 [0.3] vs 37.7 [0.3] °C: P = .036, d = 0.75), and the SCI group experienced a higher peak Tcore for INT compared with control (39.0 [0.4] vs 38.6 [0.6] °C; P = .004). Peak Tcore occurred later in the ISP for players with SCI (96 [5.8] vs 48 [2.7]min; P < .001). All players reported a higher thermal sensation and thermal comfort following INT (P < .001), with no differences between conditions throughout the ISP. No significant differences were found in wheelchair performance variables during the ISP between conditions (P ≥ .143). The high-INT WU increased thermal strain in the SCI group during the ISP, potentially due to increased metabolic heat production and impaired thermoregulation, while not impacting on repeated sprint performance. It may be advisable to limit high-INT bouts during a WU in players with SCI to mitigate issues related to hyperthermia in subsequent performance.

High-Intensity Warm-Up Increases Anaerobic Energy Contribution during 100-m Sprint.

Simple SummaryCertain exercise performances or movements cause sudden changes (or increases) in metabolic response. Track and field running events that require explosive energy in the shortest time, such as a 100-m sprint, need an immediate energy supply. Referring to the relevant studies to date, metabolic responses to submaximal exercise have been well documented, while information on the metabolic responses of short-term sprint performance is relatively insufficient. In this regard, based on the evidence that the human body relies on anaerobic energy metabolism during intense, short-term exercise, we investigated anaerobic energy contributions following the acute effect of a high-intensity warm-up during a 100 m-sprint. The main finding of our study revealed that a high-intensity warm-up (HIW) increases the contribution of the anaerobic system, probably by activating key regulatory enzymes related to anaerobic energy metabolism, compared to a low-intensity warm-up, for a 100-m sprint. Therefore, an HIW is effective in increasing anaerobic energy contribution during a 100-m sprint, which can be a useful strategy for coaches and athletes in the field.This study aimed to evaluate the effects of warm-up intensity on energetic contribution and performance during a 100-m sprint. Ten young male sprinters performed 100-m sprints following both a high-intensity warm-up (HIW) and a low-intensity warm-up (LIW). Both the HIW and LIW were included in common baseline warm-ups and interventional warm-ups (eight 60-m runs, HIW; 60 to 95%, LIW; 40% alone). Blood lactate concentration [La−], time trial, and oxygen uptake (VO2) were measured. The different energy system contribution was calculated by using physiological variables. [La−1]Max following HIW was significantly higher than in LIW (11.86 ± 2.52 vs. 9.24 ± 1.61 mmol·L−1; p < 0.01, respectively). The 100-m sprint time trial was not significantly different between HIW and LIW (11.83 ± 0.57 vs. 12.10 ± 0.63 s; p > 0.05, respectively). The relative (%) phosphagen system contribution was higher in the HIW compared to the LIW (70 vs. 61%; p < 0.01, respectively). These results indicate that an HIW increases phosphagen and glycolytic system contributions as compared to an LIW for the 100-m sprint. Furthermore, an HIW prior to short-term intense exercise has no effect on a 100-m sprint time trial; however, it tends to improve times (decreased 100-m time trial; −0.27 s in HIW vs. LIW).

The effects of high-intensity warm-up sets on bench press strength

Abstract Aims: Movement specific warm-up is a widely accepted practice in the sports environment; however, little is known regarding the ideal intensity of its performance. To verify the effects of adding high-intensity sets to the warm-up on strength, muscular electrical activity, and body temperature in the bench press exercise. Methods: Twelve men (21±1.7 years, 23.9±3.5 kg.m2) were evaluated by a maximal repetition test (1-RM), after which the volunteers performed three procedures: Low-intensity warm-up (LIW), low-intensity warm-up with high-intensity sets (WHI), and no warm-up (CON). Next, they performed maximal isometric voluntary contractions (MIVC) of the chest press to assess the electromyographic activity of the pectoralis major, peak rate of force, development (RFDpeak), and maximum strength (Smax). The skin temperature was evaluated before starting the test. Results: No between-condition differences (p≤0.05) were found for Smax (CON = 320.3±83.8 N; LIW = 300.1±131.6 N, HIW = 327.0±113.9 N; p = 0.689), RFDpeak (CON = 4399±1776 Ns-1; LIW = 3476±1905 Ns-1; HIW = 4715±2184 Ns-1; p = 0.243), skin temperature (CON = 34.0±1.0 °C, LIW = 34.9±0.8 °C, HIW = 34.8±1.1 °C; p = 0.078) or myoelectric activity according to the root mean square index of sternocostal (p = 0.402) and clavicular (p = 0.535) heads, as well as the median frequency data of sternocostal (p = 0.169) and clavicular heads (p = 0.456). Conclusion: In conclusion, the proposed warm-up protocols were not able to modify strength, muscle electrical activity, or skin temperature in the bench press exercise.

Correction: Effects of High-intensity Warm-ups on Running Performance.

Correction: Effects of High-intensity Warm-ups on Running Performance.

Effects of High-intensity Warm-ups on Running Performance.

The objective of this study was to determine the effects of high-intensity warm-ups (WUs) on performance, physiological, neuromuscular and biomechanical parameters. Three randomized cross-over 105%vVO2max time limit trials (TLimT) were performed by 11 well-trained runners following three different WU protocols. These included two experimental high-intensity variants and one control WU variant: (i) 9x20-sec level strides (105%vVO2max; 1% gradient) with 60 s of recovery (level); (ii) 6x6-sec uphill strides (105%vVO2max; 5% gradient), with the same recovery (uphill) and (iii) 7 min at 60%vVO2max as control condition (control). The uphill and level WUs resulted in a greater performance during TLimT (160.0±6.62 s and 152.64±10.88 s, respectively) compared to control WUs (144.82±6.60 s). All WU conditions reduced the energy cost (EC) of running, respiratory exchange ratio, and step frequency (SF) after the experimental and control phases of WU, while blood lactate (BLC) increased in uphill and level WUs and decreased in control WUs. Changes in kinematic variables were found without differences between WU conditions during TLimT. BLC rose at conclusion of TLimT without differences between WU conditions. Both high-intensity WUs show a longer TLimT. EC is deteriorated after the high-intensity WU exercise due to a change of substrate utilization, increase of BLC and SF. A long transient phase (18 min) is necessary to avoid impairing the performance.

Effects of work-matched moderate- and high-intensity warm-up on power output during 2-min supramaximal cycling.

We tested the hypothesis that compared with a moderate-intensity warm-up, a work-matched high-intensity warm-up improves final-sprint power output during the last 30 s of a 120-s supramaximal exercise that mimics the final sprint during events such as the 800-m run, 1,500-m speed skate, or Keirin (cycling race). Nine active young males performed a 120-s supramaximal cycling exercise consisting of 90 s of constant-workload cycling at a workload that corresponds to 110% peak oxygen uptake (VO2peak) followed by 30 s of maximal cycling. This exercise was preceded by 1) no warm-up (control), 2) a 10-min cycling warm-up at a workload of 40% VO2peak (moderate-intensity), or 3) a 5-min cycling warm-up at a workload of 80% VO2peak (high-intensity). Total work was matched between the two warm-up conditions. Both warm-ups increased 5-s peak (observed within 10 s at the beginning of maximal cycling) and 30-s mean power output during the final 30-s maximal cycling compared to no warm-up. Moreover, the high-intensity warm-up provided a greater peak (577±169 vs. 541±175 W, P=0.01) but not mean (482±109 vs. 470±135W, P=1.00) power output than the moderate-intensity warm-up. Both VO2 during the 90-s constant workload cycling and the post-warm-up blood lactate concentration were higher following the high-intensity than moderate-intensity warm-up (all P≤0.05). We show that work-matched moderate- (~40% VO2peak) and high- (~80% VO2peak) intensity warm-ups both improve final sprint (~30 s) performance during the late stage of a 120-s supramaximal exercise bout, and that a high-intensity warm-up provides greater improvement of short-duration (<10 s) maximal sprinting performance.

The Effects Of A Low And High Intensity Warm-up On Running Economy In Distance Runners

An effective warm-up may improve running economy (RE, steady-state consumption of oxygen (VO2)) in runners prior to competition due to acute increases in VO2, blood lactate (BL), and heart rate (HR), which may lead to increased performance. PURPOSE: The purpose of this study was to compare the effects of a short (3 min) high-intensity (HI, 85% of VO2max) warm-up to a longer (15 minutes) low-intensity (LI, 60% of VO2max) warm-up on physiological factors (RE, VO2, BL, and HR) associated with improved performance. METHODS: Ten, young (mean ± SD, 27.9 ± 2.0y) trained (VO2max, 65.4 ± 4.7 ml/kg/min) male distance performed a HI and LI warm-ups in a counterbalanced randomized order separated by 7d. Immediately after performing each warm-up, subjects stood for 10 minutes to mimic the typical rest period before the start of a race followed by a 30 minute RE test at 75% VO2max. RE, expressed as the steady-state VO2, BL, and HR were determined pre warm-up, following a 10 minute rest period, and minutes 10 and 30 of the RE test. RESULTS: Both warm up significantly increased pre-economy run VO2 by ∼22 ± 5.0% with no difference between warm-up types (P>0.05). Pre-economy run BL was significantly (P>0.05) higher in the HI (55.5 ± 61.6%) compared to the LI (16.4 ± 20.1%) protocol. However, neither had a significant effect (P>0.05) on improving RE at either minute 10 (49.2 ± 3.7 to 48.9 ± 3.5 ml/kg/min) or 30 (49.7 ± 3.6 to 49.2 ± 3.5 ml/kg/min) of the economy run. CONCLUSION: Performing either a LI or HI intensity warm-up improves factors associated with increased RE but return to pre warm-up levels after only a few minutes of rest (<5min), therefore, reducing the impact on improving RE. Therefore we recommend that rest periods following warm-up to the start of the race be minimized (<5min) to maximize the effect of the warmup.

Day 2. Posters – Sport and Performance

Research investigating the most effective warm-up intensity for subsequent running performance is somewhat varied. When compared to a low-intensity warm-up, Ingham et al. (2013, International Journal of Sports Physiology and Performance, 8, 77–83) found that a high-intensity warm-up significantly improved 800-m running performance in trained runners, whereas Wittekind and Beneke (2008, Journal of Science and Medicine in Sport, 12, 480–484) found that a high-intensity warm-up did not improve run time to exhaustion. The aim of this study was to assess whether a high-intensity warm-up results in a quicker 5-km running time compared to a low-intensity or no warm-up. Eight male recreational competitive runners (23.3 ± 3.6 years, 73 ± 6.4 kg, 178 ± 4.4 cm) completed a timed 5-km treadmill run after completing three warm-up protocols in randomised order, including control condition (C) (no warm-up), a low-intensity (LI) warm-up (5-min self-paced jogging), and a high-intensity (HI) warm-up (5-min self-paced jogging plus four 15-s sprints). Heart rate, ratings of perceived exertion (RPE) and running speed were measured after each kilometre. Blood lactate was measured after each warm-up protocol and upon completing 5-km performances. Ethical approval was granted by the local ethics committee. There was no significant difference (ANOVA: P = 0.80) in 5-km times between trials (HI: 22:13 ± 3:33; LI: 21:54 ± 3:30; C: 22:09 ± 3:20 min) though HI ran the slowest 5 km; running speed was not significantly different after each kilometre, although HI had the highest running speed after 1 km (HI: 14.7 ± 2.7; LI: 14.4 ± 2.3; C: 14 ± 2.4 km · h−1) and slowest at 5 km. Blood lactate concentrations were significantly different (P = 0.02) post warm-up between trials (HI: 3.7 ± 1.1; LI: 2.6 ± 0.7; C: 1 ± 0.1 mmol · l−1), but not significantly different (P = 0.42) after completing 5 km (HI: 6.5 ± 0.9; LI: 6.2 ± 0.9; C: 6.3 ± 0.7 mmol · l−1). Heart rate was similar at each kilometre (P > 0.05); RPE was highest for HI at each kilometre but was only significantly higher (Wilcoxon: P = 0.03; effect size 0.513) at 1 km for HI (14.4 ± 1.1) compared to LI (13.2 ± 0.9). The findings of the study indicate that a high-intensity warm-up does not benefit running performance, similar to findings previously reported (e.g. Wittekind and Beneke, 2008). It is possible that HI resulted in participants starting the 5-km run at too fast a pace coinciding with elevated RPE; this pace could not be maintained and was detrimental to pace later in the run.

Improvement of 800-m Running Performance With Prior High-Intensity Exercise

Prior high-intensity exercise increases the oxidative energy contribution to subsequent exercise and may enhance exercise tolerance. The potential impact of a high-intensity warm-up on competitive performance, however, has not been investigated. To test the hypothesis that a high-intensity warm-up would speed VO2 kinetics and enhance 800-m running performance in well-trained athletes. Eleven highly trained middle-distance runners completed two 800-m time trials on separate days on an indoor track, preceded by 2 different warm-up procedures. The 800-m time trials were preceded by a 10-min self-paced jog and standardized mobility drills, followed by either 6 × 50-m strides (control [CON]) or 2 × 50-m strides and a continuous high-intensity 200-m run (HWU) at race pace. Blood [La] was measured before the time trials, and VO2 was measured breath by breath throughout exercise. 800-m time-trial performance was significantly faster after HWU (124.5 ± 8.3 vs CON, 125.7 ± 8.7 s, P < .05). Blood [La] was greater after HWU (3.6 ± 1.9 vs CON, 1.7 ± 0.8 mM; P < .01). The mean response time for VO2 was not different between conditions (HWU, 27 ± 6 vs CON, 28 ± 7 s), but total O2 consumed (HWU, 119 ± 18 vs CON, 109 ± 28 ml/kg, P = .05) and peak VO2 attained (HWU, 4.21 ± 0.85 vs CON, 3.91 ± 0.63 L/min; P = .08) tended to be greater after HWU. These data indicate that a sustained high-intensity warm-up enhances 800-m time-trial performance in trained athletes.

Effect of Warm-Up Exercise on Exercise-Induced Bronchoconstriction

Exercise-induced bronchoconstriction (EIB) occurs when vigorous exercise induces bronchoconstriction. Preexercise warm-up routines are frequently used to elicit a refractory period and thus reduce or prevent EIB. This study aimed to conduct a systematic review to evaluate the effectiveness of preexercise routines to attenuate EIB. A comprehensive literature search was performed, with steps taken to avoid publication and selection bias. Preexercise warm-up routines were classified into four groups: interval high intensity, continuous low intensity, continuous high intensity, and variable intensity (i.e., a combination of low intensity up to very high intensity). The EIB response was measured by the percent fall in the forced expiratory volume in 1 s (FEV1) after exercise, and the mean differences (MDs) and 95% confidence intervals (CI) are reported. Seven randomized studies met the inclusion criteria. The pooled results showed that high intensity (MD = -10.6%, 95% CI = -14.7% to -6.5%) and variable intensity (MD = -10.9%, 95% CI = -14.37% to -7.5%) exercise warm-up attenuated the fall in FEV1. However, continuous low-intensity warm-up (MD = -12.6%, 95% CI = -26.7% to 1.5%) and continuous high-intensity warm-up (MD = -9.8%, 95% CI = -26.0% to 6.4%) failed to result in a statistically significant reduction in bronchoconstriction. The most consistent and effective attenuation of EIB was observed with high-intensity interval and variable intensity preexercise warm-ups. These findings indicate that an appropriate warm-up strategy that includes at least some high-intensity exercise may be a short-term nonpharmacological strategy to reducing EIB.

High-intensity warm-ups elicit superior performance to a current soccer warm-up routine

Objectives: This study investigated the acute effects of a currently implemented team-sport warm-up and two alternative, high-intensity, short-duration protocols – 5 repetition maximum leg press and small-sided games. Design: Ten male soccer players participated in a randomised, cross-over study. Methods: Participants performed a team-sport, a leg-press, or a small-sided game warm-up. Subsequent performance tests included counter-movement jump, reactive agility, and 15 × 20 m sprints embedded in an intermittent exercise task. Physiological measures included core temperature, blood lactate concentration, heart rate and rating of perceived exertion. Data were analysed using the effect size statistic with 90% confidence intervals, and percentage change, to determine magnitude of effects. Results: Counter-movement jump height improved following the small-sided game (6%, ES: 0.8 ± 0.8) and leg-press warm-up (2%, ES: 0.3 ± 0.5), but not after the team-sport warm-up (‘unclear’ effect). Reactive agility improved after the small-sided game (4%, ES: 0.8 ± 0.7) and leg-press warm-ups only (5%, ES: 1.1 ± 0.7), when compared to baseline. Mean 20-m sprint times during the intermittent exercise task improved following the leg-press warm-up, when compared with the small-sided game (9%, ES: 0.9 ± 0.3) and team-sport warm-ups (7%, ES: 0.6 ± 0.6). Core temperature was lower following the leg-press warm-up compared to small-sided game (1%, ES: 0.9 ± 0.7) and the team-sport WUs (2%, ES: 2.4 ± 0.8). Blood lactate was highest following the small-sided game (67%, ES: 2.7 ± 0.8) and team-sport warm-ups (66%, ES: 2.9 ± 0.9). Conclusions: A leg-press and small-sided game warm-up may improve acute team-sport performance tests when compared to a traditional warm-up protocol.

The Effects of High Intensity Warm-Up on Shot Put Performance

The Effects of High Intensity Warm-Up on Shot Put Performance

Effects of three warm‐up regimens of equal distance onV̇o2kinetics during supramaximal exercise in Thoroughbred horses

Several studies have indicated that even low-intensity warm-up increases O(2) transport kinetics and that high-intensity warm-up may not be needed in horses. However, conventional warm-up exercise for Thoroughbred races is more intense than those utilised in previous studies of equine warm-up responses. To test the hypothesis that warm-up exercise at different intensities alters the kinetics and total contribution of aerobic power to total metabolic power in subsequent supramaximal (sprint) exercise in Thoroughbred horses. Nine well-trained Thoroughbreds ran until fatigue at 115% of maximal oxygen consumption (VO2max) 10 min after warming-up under each of 3 protocols of equal running distance: 400 s at 30% VO2max (LoWU), 200 s at 60% VO2max (MoWU) and 120 s at 100% VO2max (HiWU). Variables measured during exercise were rates of O(2) and CO(2) consumption/production (VO2,VO2), respiratory exchange ratio (RER), heart rate, blood lactate concentration and accumulation rate and blood gas variables. VO2 was significantly higher in HiWU than in LoWU at the onset of the sprint exercise and HR was significantly higher in HiWU than in LoWU throughout the sprint. Accumulation of blood lactate, RER, P(a)CO(2) and PvCO2 in the first 60 s were significantly lower in HiWU than in LoWU and MoWU. There were no significant differences in stroke volume, run time or arterial-mixed venous O(2) concentration. These results suggest HiWU accelerates kinetics and reduces reliance on net anaerobic power compared with LoWU at the onset of the subsequent sprint.

Effects of warm-up intensity on oxygen transport during supramaximal exercise in horses

To determine whether warm-up exercise at different intensities alters kinetics and total contribution of aerobic power to total metabolic power in subsequent supramaximal exercise in horses. 11 horses. Horses ran at a sprint until fatigued at 115% of maximal oxygen consumption rate (VO(2max)), beginning at 10 minutes following each of 3 warm-up protocols: no warmup (NoWU), 1 minute at 70% VO(2max) (moderate-intensity warm-up [MoWU]), or 1 minute at 115% VO(2max) (high-intensity warm-up [HiWU]). Cardiopulmonary and blood gas variables were measured during exercise. The VO(2) was significantly higher in HiWU and MoWU than in NoWU throughout the sprint exercise period. Blood lactate accumulation rate in the first 60 seconds was significantly lower in MoWU and HiWU than in NoWU. Specific cardiac output after 60 seconds of sprint exercise was not significantly different among the 3 protocols; however, the arterial mixed-venous oxygen concentration difference was significantly higher in HiWU than in NoWU primarily because of decreased mixed-venous saturation and tension. Run time to fatigue following MoWU was significantly greater than that with NoWU, and there was no difference in time to fatigue between MoWU and HiWU. HiWU and MoWU increased peak values for VO(2) and decreased blood lactate accumulation rate during the first minute of intense exercise, suggesting a greater use of aerobic than net anaerobic power during this period.

Comparative Effects of a High-Intensity Interval Warm-Up and Salbutamol on the Bronchoconstrictor Response to Exercise in Asthmatic Athletes

Comparative Effects of a High-Intensity Interval Warm-Up and Salbutamol on the Bronchoconstrictor Response to Exercise in Asthmatic Athletes

Comparative Effects of a High-Intensity Interval Warm-Up and Salbutamol on the Bronchoconstrictor Response to Exercise in Asthmatic Athletes

Approximately half of all asthmatics become refractory to exercise-induced bronchoconstriction (EIB) with repeated challenges. Exercise refractoriness has been utilized by asthmatic athletes to reduce the bronchoconstrictor response to exercise prior to competition, and this has led to the observation that some asthmatic athletes can "run through" their asthma. The main aim of this study was to investigate the efficacy of short high-intensity, repeated warm-ups compared with salbutamol (a commonly used inhaled beta (2)-agonist) on the severity of EIB. Eight moderately trained (.VO(2peak), 51.9 +/- 2.3 ml . kg (-1) . min (-1)) recreational asthmatic athletes with documented EIB were tested under 4 experimental conditions: 1) control (CON) condition; 2) an interval warm-up (WU) consisting of 8 x 30-sec runs at peak treadmill speed, with 45-sec recovery between each sprint; 3) inhaling 200 microg of salbutamol (Ventolin, GlaxoSmithKline, Uxbridge, Middlesex, U.K.) (IH); and 4) combining both the WU and IH session. All 4 experimental sessions were followed by an exercise challenge test (85-90 % predicted maximum heart rate for 8 min). Pulmonary function was measured pre-exercise and at 1, 5, 10, 15 min postexercise. The mean maximum percent fall in pre- to postexercise forced expiratory volume in 1-sec (FEV (1)) for all 8 asthmatic subjects during the EIB screening test (CON session) was - 18.25 +/- 4.01 %. The mean maximum percent decrease in postexercise FEV (1) significantly decreased (p < 0.05) to only - 9.1 +/- 0.6 % following the WU condition, which is below the EIB diagnostic threshold of a 10 % fall in postexercise FEV (1). The IH and WU + IH condition resulted in a substantial postexercise bronchodilation as shown by a significant increase (p < 0.05) in the mean maximum percent change in postexercise FEV (1) following the IH (+ 8.9 +/- 6.1 %) and WU + IH (+ 15.2 +/- 4.6 %) condition. Similar changes as a result of experimental condition were observed for FEF (25-75 %). These data indicate that repeated high-intensity warm-ups can lessen the bronchoconstrictor response to exercise. In addition, combining the interval warm-up with salbutamol prior to exercise resulted in substantial bronchodilation and conferred a greater protective effect against developing EIB than either intervention alone.

The effect of an intermittent, high-intensity warm-up on supramaximal kayak ergometer performance

It has previously been shown that the metabolic acidaemia induced by a continuous warm-up at the 'lactate threshold' is associated with a reduced accumulated oxygen deficit and decreased supramaximal performance. The aim of this study was to determine if an intermittent, high-intensity warm-up could increase oxygen uptake (V02) without reducing the accumulated oxygen deficit, and thus improve supramaximal performance. Seven male 500 m kayak paddlers, who had represented their state, volunteered for this study. Each performed a graded exercise test to determine V02max and threshold parameters. On subsequent days and in a random, counterbalanced order, the participants then performed a continuous or intermittent, high-intensity warm-up followed by a 2 min, all-out kayak ergometer test. The continuous warm-up consisted of 15 min of exercise at approximately 65% V02max. The intermittent, high-intensity warm-up was similar, except that the last 5 min was replaced with five 10 s sprints at 200% V02max, separated by 50 s of recovery at ~55% V02max. Significantly greater (P<0.05) peak power (intermittent vs continuous: 629 ± 199 vs 601 ± 204W) and average power (intermittent vs continuous: 328±39.0 vs 321 ±42.4 W) were recorded after the intermittent warm-up. There was no significant difference between conditions for peak V02, total V02 or the accumulated oxygen deficit. The results of this study indicate that 2 min all-out kayak ergometer performance is significantly better after an intermittent rather than a continuous warm-up.