ABSTRACT

1. -Excess Post-Exercise Oxygen Consumption (EPOC) Following Multiple Effort Sprint and Moderate Aerobic Exercise. Jeremy R. Townsend1, Aaron B. Morton2, Adam R. Jajtner1, Adam Gonzalez 1, Gerald T. Mangine1, Adam J. Wells 1, Maren S. Fragala1, Edward Robinson IV1, William P. McCormack1, Jeffrey R. Stout FACSM1,Jay R. Hoffman FACSM1 and Ludmila Cosio-Lima2 1 Institute of Exercise Physiology & Wellness, University of Central Florida, Orlando, FL, 2Human Performance Laboratory, University of West Florida, Pensacola, FL, USA, SUMMARY & CONCLUSIONS ABSTRACT RESULTS METHODS • The unique finding of this study was that brief repeated bouts of maximal exercise produce EPOC values that are higher in length and magnitude compared to continuous aerobic exercise. • The EPOC values (7.5L) observed during recovery post RS were similar or greater to values (2.3-6.2L) reported in previous studies utilizing traditional resistance exercise sessions which lasted 2 to 6 times longer than RS 4,7,8 • Oxygen consumption remained elevated during the entire recovery period of 30 min in RS, whereas MA only elicited an increase for 6 min post exercise then returned to baseline. • 37.5 kcal increase was observed during the 30-min of significantly elevated VO2 in the anaerobic trial. • In conclusion, the data suggest that RS bouts of exercise produce a significantly greater magnitude (301%) and duration (400%) of EPOC than MA exercise. • Future studies involving a greater number of subjects and heterogeneous populations are needed to further understand post-exercise metabolic rate. • Since VO2 remained elevated at the end of the 30-min recovery period, further investigation examining longer durations of EPOC is warranted to determine how long REE can potentially remain elevated following RS exercise protocols. • Exercise Sessions • Prior to each testing session, baseline VO2 will be assessed by collecting and analyzing expired gases. • Participants then completed one of two testing trials • (a) 30-min submaximal cycling bout at 60% of heart rate reserve (HRR) as determined by the Karvonen method6(b) Three repeated 30-second Wingate cycling tests separated by 4 min each. • Each testing trial was separated by 48 hrs and was implemented in random counterbalanced design. • Following testing trials, supine VO2was measured for 30 min or until baseline measures were reached. • A participant was considered to have reached baseline when the average of two consecutive minutes was equal to baseline values. • EPOC will be determined by subtracting baseline VO2 from post exercise VO2 measurements. PURPOSE: To investigate the effects of repeated bouts of intense 30-second all-out sprint exercise (RS) vs. moderate aerobic exercise (MA) on EPOC. METHODS:Six recreationally-trained males (age = 23.3 ± 1.4 yrs, weight = 81.8 ± 9.9 kg, height = 180.8 ± 6.3cm) completed three repeated 30-second Wingate cycling tests and a 30-min cycling bout at 60% HRR in a random counterbalanced design. Each 30-second cycling bout was separated by 4 min with the total RS session lasting ~11 min. Baseline oxygen consumption (VO2) was determined by an average VO2 from the final 5 min of a 30-min supine rest period prior to each trial. Following each protocol, VO2 was measured for 30-min or until baseline measures were reached. EPOC was determined by subtracting baseline VO2 from post exercise VO2 measurements. Energy expenditure (kcals) was determined by multiplying kcals per liter of oxygen by the average VO2 during recovery. RESULTS:EPOC values were significantly higher in RS (7.5±1.3 L) than MA (1.8±0.7 L). RS produced a higher recovery caloric expenditure (37.5 kcals) compared to MA (9.8 kcals) and remained significantly elevated (p=0.024) over resting levels during the entire recovery period (30min) compared to MA (6 min, p=0.003). CONCLUSION: The energy required to recover from three repeated maximal effort 30-second Wingate cycling tests was greater than 30-min of moderate aerobic exercise. Future studies should examine the chronic effects of maximal effort sprint training protocol on cardiovascular fitness and body composition. • No differences were seen in baseline VO2 measures between the two trials (p= 0.90, RSpre: 3.74 ml·kg-1·min-1 vs. MApre: 3.72 ml·kg-1·min-1). • Wingate performance data is represented in Table 2. Following exercise, VO2 remained significantly elevated (p=0.024) over resting levels during the entire recovery period (30min) compared to MA (6 min, p=0.003; Table 3). • Post-exercise VO2 was significantly greater (p = 0.004) in RS at each measurement period compared to MA (Figure 1). • EPOC values were significantly higher in RS (7.5±1.3 L·O2,p = 0.012) than MA (1.8±0.65 L·O2). • RS produced a higher recovery caloric expenditure (37.5 kcals) compared to MA (9.8 kcals). • RER was significantly higher (p=0.04) in RS only in minutes 2-4. Lode Excalibur cycle ergometer. Used in MA Trials. Monark 894E Peak Bike used in RS trials. (3) Repeated Wingate Tests (3) Repeated Wingate Tests Initial Visit: Anthropometrics Familiarization INTRODUCTION 30-min Continuous Cycling 30-min Continuous Cycling • High intensity, short-duration workouts have increased in popularity in recent years. • The appeal of these types of workouts is their ability to provide an effective exercise stimulus in a short amount of time. • With adult, child, and adolescent obesity rates nearing all-time highs (35%) in the United States, an effective exercise program is needed to overcome the barriers of time and enjoyment . • Bartlett et al. (2011) recently demonstrated that high-intensity interval training was more enjoyable than continuous exercise and suggested that these types of workouts may provide better adherence and long term benefit. 3 • Short duration, intense workouts may therefore prove to be a more desirable, time efficient strategy for improving body composition and physical fitness. Study Design REFERENCES • American College of Sports Medicine (ACSM). (2009). ACSM’s guidelines for exercise testing and prescription, (8th ed.). Baltimore, MD: Lippincott, Williams & Wilkins. • Schwarzkopf, R., & Murphy, E. (1992). Effects of standard set and circuit weight training on excess post-exercise oxygen consumption. Journal of Applied Sport Science Research,6(2), 88-91. • Bartlett, J. D., Close, G. L., MacLaren, D. P., Gregson, W., Drust, B., & Morton, J. P. (2011) High-intensity interval running is perceived to be more enjoyable than moderate-intensity continuous exercise: implications for exercise adherence. Journal of sports sciences 29(6), 547-553. • Binzen, C. A., Swan, P. D., & Manore, M. M. (2001) Postexercise oxygen consumption and substrate use after resistance exercise in women. Medicine and science in sports and exercise 33(6), 932-938. • Flegal, K. M., Carroll, M. D., Kit, B. K., & Ogden, C. L. (2012). Prevalence of Obesity and Trends in the Distribution of Body Mass Index Among US Adults, 1999-2010. The Journal of the American Medical Association, 307(5), 483-490. • Karvonen MJ, Kental E, Mustala O. The effects of on heart rate a longitudinal study. Ann Med ExpFenn 1957;35(3):307-15. • Melby, C., Scholl, C., Edwards, G. , & Bullough, R. (1993) Effect of acute resistance exercise on postexercise energy expenditure and resting metabolic rate. Journal of Applied Physiology 75(4), 1847-1853. • Thornton, K. M., & Potteiger, J. A. (2002) Effects of resistance exercise bouts of different intensities but equal work on EPOC. Medicine & Science in Sports & Exercise 34(4), 715-722. • Wilmore, JH, Parr, RB, Ward, P, Vodak, PA, Barstow, TJ, Pipes, TV, Grimditch, G, and Leslie, P. Energy cost of circuit weight training. Med Sci Sports Exerc 10: 75–78, 1978. Figure 1. Comparison of mean oxygen consumption during a 30-min recovery following two exercise trials. Values are reported in ml. kg-1 . min-1 PURPOSE Supine baseline VO2 measurements To investigate the effects of repeated bouts of intense 30-second all-out sprint exercise vs. moderate aerobic exercise on EPOC.