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Concept: Excess post-exercise oxygen consumption


Ferley, DD, Osborn, RW, and Vukovich, MD. The effects of uphill vs. level-grade high-intensity interval training on V[Combining Dot Above]O2max, Vmax, VLT, and Tmax in well-trained distance runners. J Strength Cond Res 27(6): 1549-1559, 2013-Uphill running represents a frequently used and often prescribed training tactic in the development of competitive distance runners but remains largely uninvestigated and unsubstantiated as a training modality. The purpose of this investigation included documenting the effects of uphill interval training compared with level-grade interval training on maximal oxygen consumption (V[Combining Dot Above]O2max), the running speed associated with V[Combining Dot Above]O2max (Vmax), the running speed associated with lactate threshold (VLT), and the duration for which Vmax can be sustained (Tmax) in well-trained distance runners. Thirty-two well-trained distance runners (age, 27.4 ± 3.8 years; body mass, 64.8 ± 8.9 kg; height, 173.6 ± 6.4 cm; and V[Combining Dot Above]O2max, 60.9 ± 8.5 ml·min·kg) received assignment to an uphill interval training group (GHill = 12), level-grade interval training group (GFlat = 12), or control group (GCon = 8). GHill and GFlat completed 12 interval and 12 continuous running sessions over 6 weeks, whereas GCon maintained their normal training routine. Pre- and posttest measures of V[Combining Dot Above]O2max, Vmax, VLT, and Tmax were used to assess performance. A 3 × 2 repeated measures analysis of variance was performed for each dependent variable and revealed a significant difference in Tmax in both GHill and GFlat (p < 0.05). With regard to running performance, the results indicate that both uphill and level-grade interval training can induce significant improvements in a run-to-exhaustion test in well-trained runners at the speed associated with V[Combining Dot Above]O2max but that traditional level-grade training produces greater gains.

Concepts: Variance, Analysis of variance, High-intensity interval training, Running, VO2 max, Interval training, Excess post-exercise oxygen consumption, Long slow distance


Wahl, P, Zinner, C, Grosskopf, C, Rossmann, R, Bloch, W, and Mester, J. Passive recovery is superior to active recovery during a high-intensity shock microcycle. J Strength Cond Res 27(5): 1384-1393, 2013-The purpose was to examine the effects of a 2-week high-intensity shock microcycle on maximal oxygen consumption and parameters of exercise performance in junior triathletes on the one hand and to evaluate the long-term effects of active (A) vs. passive (P) recovery on the other hand. Sixteen healthy junior triathletes participated in the study. For the assignment to the A or P group, the subjects were matched according to age and performance. Within 2 weeks, a total of 15 high-intensity interval sessions within three 3-day training blocks were performed. Before and 1 week after the last training session, the athletes performed a ramp test to determine V[Combining Dot Above]O2max, a time trial (TT) and a Wingate test. Furthermore, total hemoglobin (Hb) mass was determined. The results of the whole group, independent of the arrangement of recovery, were analyzed at first; second, the A and P groups were analyzed separately. Peak power output (PPO) during the ramp test and TT performance significantly increased in the whole group. The comparison of the 2 groups revealed increases for the mentioned parameters and for V[Combining Dot Above]O2 and power output at VT2 for the P group only. The V[Combining Dot Above]O2max did not change. Wingate performance increased in the A group only. The tHb mass slightly decreased. The main finding of this study was that a 14-day shock microcycle is able to improve TT performance and PPO in junior triathletes in a short period of time. Furthermore, not only the intensity but also the arrangement of interval training seems to be important as well, because only the P group showed improvements in endurance performance, despite a slightly lower training volume. These findings might be relevant for future arrangements of high-intensity interval training.

Concepts: Time, Exercise, English-language films, High-intensity interval training, Interval training, Excess post-exercise oxygen consumption, Arrangement, Long slow distance


It has been hypothesized that exercise-induced changes in metabolites and ions are crucial in the adaptation of contracting muscle. We tested this hypothesis by comparing adaptations to two different interval-training protocols (differing only in the rest duration between intervals), which provoked different perturbations in muscle metabolites and acid-base status. Prior to and immediately after training, 12 women performed the following tests: (1) a graded exercise test to determine peak oxygen uptake ( ); (2) a high-intensity exercise bout (followed 60 s later by a repeated-sprint-ability test; and (3) a repeat of the high-intensity exercise bout alone with muscle biopsies pre-exercise, immediately postexercise and after 60 s of recovery. Subjects performed 5 weeks (3 days per week) of training, with either a short (1 min; HIT-1) or a long rest period (3 min; HIT-3) between intervals; training intensity and volume were matched. Muscle [H(+)] (155 ± 15 versus 125 ± 8 nmol l(-1); P < 0.05) and muscle lactate content (84.2 ± 7.9 versus 46.9 ± 3.1 mmol (g wet weight)(-1)) were both higher after HIT-1, while muscle phosphocreatine (PCr) content (52.8 ± 8.3 versus 63.4 ± 9.8 mmol (g wet weight)(-1)) was lower. There were no significant differences between the two groups regarding the increases in , repeated-sprint performance or muscle Na(+),K(+)-ATPase content. Following training, both groups had a significant decrease in postexercise muscle [H(+)] and lactate content, but not postexercise ATP or PCr. Postexercise PCr resynthesis increased following both training methods. In conclusion, intense interval training results in marked improvements in muscle Na(+),K(+)-ATPase content, PCr resynthesis and . However, manipulation of the rest period during intense interval training did not affect these changes.

Concepts: Exercise, Following, English-language films, Lactic acid, High-intensity interval training, Interval training, Excess post-exercise oxygen consumption, Long slow distance


Ho, SR, Smith, RM, Chapman, PG, Sinclair, PJ, and Funato, K. Physiological and physical characteristics of elite dragon boat paddlers. J Strength Cond Res 27(1): 137-145, 2013-The objectives of this study were to profile the physiological and physical characteristics of elite dragon boat paddlers, to identify characteristics that predict race performance and to quantify the metabolic energy contributions to simulated 200-m and 500-m dragon boat racing. Eleven, national level, male, Japanese dragon boat paddlers completed a battery of tests on a paddling ergometer including an incremental maximal aerobic capacity test, a 2-minute maximal accumulated oxygen deficit (MAOD) test, and simulated 200-m and 500-m races. A physiological and physical profile of subjects was compiled. Results showed that 200-m race performance correlated with flexed arm girth and excess postexercise oxygen consumption (EPOC) measured in the 30 minutes after the MAOD test, whereas 500-m race performance correlated with body fat percentage, relaxed and flexed arm girth, MAOD, EPOC, and peak power during the MAOD test. Stepwise multiple regression revealed that flexed arm girth was the most powerful predictor of 200-m and 500-m race performance, followed by EPOC with the combination of these 2 factors able to explain 74% and 68% of the variance in 200-m and 500-m race performance, respectively. Aerobic energy contributions for 200-m (50 seconds) and 500-m (1 minute 50 seconds) races were (mean (95% confidence intervals)) 52.1% (range, 47.4-56.8%) and 67.5% (range, 60.1-77.8%), respectively. In conclusion, coaches should develop training programs targeted at developing upper-body musculature and increasing anaerobic capacity because these factors are the strongest predictors of 200-m and 500-m race performance. Given the substantial aerobic energy contributions even for a 200-m race event, coaches should aim to increase the maximal aerobic capacity of the paddler in preparation for both 200-m and 500-m events.

Concepts: Adipose tissue, Exercise physiology, Aerobic exercise, Excess post-exercise oxygen consumption, Anaerobic exercise, Canoe, Chinese dragon, Dragon boat


Previous research combining Calcium β-hydroxy-β-methylbutyrate (CaHMB) and running high-intensity interval training (HIIT) have shown positive effects on aerobic performance measures. The purpose of this study was to examine the effect of β-hydroxy-β-methylbutyric free acid (HMBFA) and cycle ergometry HIIT on maximal oxygen consumption (VO2peak), ventilatory threshold (VT), respiratory compensation point (RCP) and time to exhaustion (Tmax) in college-aged men and women.

Concepts: Protein, Cellular respiration, Exercise physiology, High-intensity interval training, Running, Interval training, Excess post-exercise oxygen consumption, Long slow distance


The purpose of this study was to compare the effectiveness of a novel exercise protocol we developed for kettlebell high-intensity interval training (KB-HIIT) by comparing the cardiorespiratory and metabolic responses to a standard sprint interval cycling (SIC) exercise protocol. Eight men volunteered for the study and completed two preliminary sessions, followed by two 12-minute sessions of KB-HIIT and SIC in a counterbalanced fashion. In the KB-HITT session, three circuits of four exercises were performed using a Tabata regimen. In the SIC session, three 30-second sprints were performed, with 4-minutes of recovery in between the first two sprints and 2.5-minutes of recovery after the last sprint. A within-subjects design over multiple time points was used to compare oxygen consumption (VO2), respiratory exchange ratio (RER), tidal volume (TV), breathing frequency (f), minute ventilation (VE), caloric expenditure rate (kcalmin), and heart rate (HR) between the exercise protocols. Additionally, total caloric expenditure was compared. A significant group effect, time effect, and group x time interaction were found for VO2, RER, and TV, with VO2 being higher and TV and RER being lower in the KB-HIIT compared to the SIC. Only a significant time effect and group x time interaction were found for f, VE, kcalmin, and HR. Additionally, total caloric expenditure was found to be significantly higher during the KB-HIIT. The results of the present study suggest that KB-HIIT may be more attractive and sustainable than SIC, and can be effective in stimulating cardiorespiratory and metabolic responses that could improve health and aerobic performance.

Concepts: Comparison, Effectiveness, Exercise, Comparisons, High-intensity interval training, Interval training, Excess post-exercise oxygen consumption, Long slow distance


Subjects performed high-intensity interval training (HIIT) and continuous moderate-intensity training (END) to evaluate 24-h oxygen consumption. Oxygen consumption during HIIT was lower versus END; however, total oxygen consumption over 24 h was similar. These data demonstrate that HIIT and END induce similar 24-h energy expenditure, which may explain the comparable changes in body composition reported despite lower total training volume and time commitment.

Concepts: Adenosine triphosphate, Fundamental physics concepts, Exercise, High-intensity interval training, Endurance, Interval training, Excess post-exercise oxygen consumption, Long slow distance


BACKGROUND: The purpose of this study was to reveal any association between cardiorespiratory fitness level and excess post-exercise oxygen consumption (EPOC) using three cycling protocols with varying degrees of exercise intensity, i.e., sprint interval training (SIT), high-intensity interval aerobic training (HIAT), and continuous aerobic training (CAT). FINDINGS: Ten healthy men, aged 20 to 31 years, attended a cross-over experiment and completed three exercise sessions: SIT consisting of 7 sets of 30-s cycling at 120% VO2max with a 15-s rest between sets; HIAT consisting of 3 sets of 3-min cycling at 80~90% VO2max with a 2-min active rest at 50% VO2max between sets; and CAT consisting of 40 min of cycling at 60~65% VO2max. During each session, resting VO2, exercise VO2, and a 180-min post-exercise VO2 were measured. The net exercise VO2 during the SIT, HIAT, and CAT averaged 14.7 +/- 1.5, 31.8 +/- 4.1, and 71.1 +/- 10.0 L, and the EPOCs averaged 6.8 +/- 4.0, 4.5 +/- 3.3, and 2.9 +/- 2.8 L, respectively. The EPOC with SIT was greater than with CAT (P < 0.01) and HIAT (P = 0.12). Correlation coefficients obtained between subjects' VO2max and the ratio of EPOC to net exercise VO2 for SIT, HIAT, and CAT were -0.61 (P = 0.06), -0.79 (P < 0.01), and -0.42 (P = 0.23), respectively. CONCLUSIONS: Our data suggest that cardiorespiratory fitness level correlates negatively with the magnitude of EPOC, especially when performing aerobic-type interval training.

Concepts: Exercise, Cycling, Exercise physiology, Cardiorespiratory fitness, VO2 max, Physical fitness, Interval training, Excess post-exercise oxygen consumption


Purpose: Excess postexercise oxygen consumption (EPOC) is dependent on intensity, duration, and mode of exercise. The purpose of this study was to compare the effect of both exercise mode and intensity on EPOC while controlling for caloric expenditure and duration. Method: Ten low to moderately physically active men (22 ± 2 yrs) performed 3 nonrandomized isocaloric bouts of exercise separated by 7 days. The 1st session was resistance training (RT), followed by moderate-intensity steady-state (SS) aerobic exercise, and concluding with a high-intensity intermittent (IT) aerobic session. Results: Total energy expenditure, rate of energy expenditure, and duration did not differ among trials (p>.05). Respiratory exchange ratio was greater during the RT trial than the SS trial (p < .05). At 12 hr postexercise, resting metabolic rate (RMR) was higher after the RT trial (4.7 ± 0.67 mL/kg/min) and IT trial (4.6 ± 0.62 mL/kg/min) compared with their respective baseline measurements (p < .008) and the SS trial (4.3 ± 0.58 mL/kg/min; p < .008). At 21 hr postexercise, RMR was higher after the RT trial (3.7 ± 0.51 mL/kg/min) and IT trial (3.5 ± 0.39 mL/kg/min) compared with the SS trial (3.2 ± 0.38 mL/kg/min; p < .008). The SS trial did not influence RMR at either 12 hr or 21 hr postexercise. Conclusion: Both RT and IT aerobic work increased EPOC to a greater degree than did SS work, indicating that either mode may be more effective at increasing total daily caloric expenditure than SS aerobic exercise.

Concepts: Metabolism, Energy, Thermodynamics, Strength training, Weight training, Exercise physiology, Basal metabolic rate, Excess post-exercise oxygen consumption


Pettitt, RW, Niemeyer, JD, Sexton, PJ, Lipetzky, A, and Murray, SR. Do the noncaffeine ingredients of energy drinks affect metabolic responses to heavy exercise? J Strength Cond Res 27(7): 1994-1999, 2013-Energy drinks (EDs) such as Red Bull (RB) are marketed to enhance metabolism. Secondary ingredients of EDs (e.g., taurine) have been purported to improve time trial performance; however, little research exists on how such secondary ingredients affect aerobic metabolism during heavy exercise. The purpose of this study was to investigate the effect of the secondary ingredients of RB on aerobic metabolism during and subsequent to heavy exercise. In double-blind, counterbalanced, and crossover fashion, 8 recreationally trained individuals completed a graded exercise test to determine the gas exchange threshold (GET). Subjects returned on 2 separate occasions and ingested either a 245 ml serving of RB or a control (CTRL) drink with the equivalent caffeine before engaging in two 10-minute constant-load cycling bouts, at an intensity equivalent to GET, with 3 minutes of rest between bouts. Accumulated liters of O2 (10 minutes) were higher for the first bout (17.1 ± 3.5 L) vs. the second bout (16.7 ± 3.5 L) but did not differ between drinks. Similarly, excess postexercise oxygen consumption was higher after the initial bout (RB mean, 2.6 ± 0.85 L; CTRL mean, 2.9 ± 0.90 L) vs. the second bout (RB mean, 1.5 ± 0.85 L; CTRL mean, 1.9 ± 0.87 L) but did not differ between drinks. No differences occurred between drinks for measures of heart rate or rating of perceived exertion. These results indicate that the secondary ingredients contained in a single serving of RB do not augment aerobic metabolism during or subsequent to heavy exercise.

Concepts: Carbon dioxide, Metabolism, Adenosine triphosphate, Cellular respiration, Coffee, Strength training, Glycolysis, Excess post-exercise oxygen consumption