Effects of high-intensity-interval-training (HIT) on cardiovascular fitness and cardiometabolic risk in the elderly.

HIT has been shown improve cardiovascular fitness and seems to induce beneficial modifications of some cardiometabolic risk factors in healthy subjects or patients. Less is known about the efficacy of HIT applied to healthy older adults. PURPOSE This proof-of-concept study tested the hypothesis that 8 weeks of HIT can induce significant improvements of cardiovascular fitness, exercise capacity and of selected cardiometabolic risk factors in healthy older adults. METHODS In 12 healthy male volunteers (68.7 ± 3.9 yy; 79.0 ± 10.8 kg; 171.4 ± 5.4 cm) who participated in the study, we measured V’O2max, gas exchange threshold (GET ) and respiratory compensation point (RCP), resting mean, systolic and diastolic blood pressures (MBP, SDP, DBP), fasting blood glucose concentration (GLU), total cholesterol/HDL ratio (TC/HDL), % Body fat (BF) and waist circumference (WC) before (PRE) and after (POST) an 8-week training program HIT consisting in 7 bouts of 2-min near-maximal cycling (i.e. 85-90 %V’O2max) interspersed with 2 minutes of recovery performed 3 times a week. RESULTS Absolute and relative V’O2max significantly increased by 5.4 % (P < 0.05; effect size, ES = 0.7) and 11.7 % (P < 0.05, ES = 0.8), respectively. V’O2 at GET and RCP increased by 7.2 % (P < 0.05, ES = 0.7) and 15.4 % (ES = 1.3), respectively. MBP, SDP and DBP decreased by 7 % (ES = 0.8), 9 % (P < 0.05, ES = 0.9) and 4 % (ns), respectively. GLU was diminished by 7 % (ES = 0.5) and TC/HDL decreased by 5 % (P < 0.05, ES = 0.2). BF and WC decreased by 4 % (ES = 0.2) and 1.4 % (P < 0.05, ES = 0.14), respectively. CONCLUSION 8 weeks of HIT promote significant changes of maximal aerobic power and exercise resistance in healthy male elderly subjects. In addition, they induce significant improvements of some selected cardiometabolic risk factors. Supported by ESA Contract Nr 4000102580