The Exercise Effect on the Anaerobic Threshold in Response to Graded Exercise

Abstract

Introduction: Anaerobic Threshold (AT) is often expressed as a percentage of VO2 max (50% 60% for the general population, 75% and above for athletes). The higher the AT, the higher intensity the athlete can sustain without producing lactic acid. Therefore, AT is a better predictor of performance than VO2 max in elite athletes. AT is often expressed as the heart rate at the ventilatory breakpoint. The heart rate at the AT can then be utilized in designing training and interval programs for athletes. Purpose: The purpose of this study was to determine the exercise effect on anaerobic threshold from the VO2 max. Methods: Eight non-athlete subjects (age 23.25±2.55 yrs, height 177.79±9.9 cm, weight 81.36±11.13 kg) of the University of Texas at Arlington volunteered to participate in this study. Each subject had their weight, height and age for entry into a metabolic cart and on a data sheet. Each subject was outfitted with the headgear, mouthpiece and nose clip. Each subject sat at rest for five minutes to collect metabolic resting data. Next, each subject performed a graded exercise test on the treadmill with increasing speed and elevation until exhaustion. During each test heart rate (HR) and rate of perceived exertion (RPE) were recorded along with the maximal values measured by the metabolic cart, relative maximal oxygen consumption (VO2max) and minute ventilation (VE). At the end of the exercise data was collected. Results: Multiple categories were measured. The average maximal values: VO2 L/min (3.39±.9), VO2 ml/kg/min (41.41±8.58), VE L/min (94.35±25.2), RQ (1.04±.18), Q L/m (23.67±5.0), SV ml/bt (125.75±25.26), a-vO2 vol% (14.1±.99), HR (187.4±14.38), SBP (175±17.5), DBP (72.5±16.2), RPE (16.62±1.6). Conclusion: The results of this study indicated that there are some significant differences found within our population sample in terms of overall cardiovascular conditioning. It is likely there were some significant differences in the subjects’ levels of conditioning before having begun the exercise. We can predict data in the measured categories will be closer to the high end of average or nearing “elite” levels of performance in subjects with more training experience compared to subjects who entered the study with a lack of conditioning. The AT and VO2 max will be achieved more rapidly in the less conditioned subjects. 1 Department of Kinesiology, University of Texas at Arlington. 226 International Journal of Health Sciences, Vol. 3(1), March 2015