EFFECT OF HIGH-INTENSITY INTERVAL TRAINING ON CARDIOVASCULAR FUNCTION, (V)over dotO2MAX, AND MUSCULAR FORCE

Astorino, TA, Allen, RP, Roberson, DW, and Jurancich, M. Effect of high-intensity interval training on cardiovascular function, <(V)over dot>O(2)max, and muscular force. J Strength Cond Res 26(1): 138-145, 2012-The purpose of this study was to examine the effects of short-term high-intensity interval training (HIIT) on cardiovascular function, cardiorespiratory fitness, and muscular force. Active, young (age and body fat = 25.3 +/- 4.5 years and 14.3 +/- 6.4%) men and women (N = 20) of a similar age, physical activity, and maximal oxygen uptake (<(V)over dot>O(2)max) completed 6 sessions of HIIT consisting of repeated Wingate tests over a 2- to 3-week period. Subjects completed 4 Wingate tests on days 1 and 2, 5 on days 3 and 4, and 6 on days 5 and 6. A control group of 9 men and women (age and body fat = 22.8 +/- 2.8 years and 15.2 +/- 6.9%) completed all testing but did not perform HIIT. Changes in resting blood pressure (BP) and heart rate (HR), <(V)over dot>O(2)max, body composition, oxygen (O-2) pulse, peak, mean, and minimum power output, fatigue index, and voluntary force production of the knee flexors and extensors were examined pretraining and posttraining. Results showed significant (p < 0.05) improvements in <(V)over dot>O(2)max, O-2 pulse, and Wingate-derived power output with HIIT. The magnitude of improvement in <(V)over dot>O(2)max was related to baseline <(V)over dot>O(2)max (r = -0.44, p = 0.05) and fatigue index (r = 0.50, p < 0.05). No change (p > 0.05) in resting BP, HR, or force production was revealed. Data show that HIIT significantly enhanced <(V)over dot>O(2)max and O-2 pulse and power output in active men and women.