Short-term and long-term impact of moderate vs vigorous integrated weight-loss programs on physiological parameters

Few studies have examined the impact of various intensities of exercise on physiological parameters during weight loss program. PURPOSE The aim of this study was to compare the short-term and long-term results of an integrated weight-loss program (BWR) on selected physiological parameters considering moderate (MI) or vigorous (HI) physical activity (PA), and the maintenance in the term of their positive effects. METHODS 24 young severely obese subjects (age, 26,38±4,72 yr; BMI, 42,62±5,28 kg/m2), divided into 2 homogeneous groups, followed a 3 weeks BWR composed by: an energy intake reduction, psychological and nutritional counselling and a customized PA program (5 training sessions/week). PA program intensity of both groups ranged between 50 and 70% of VO2max for cardiovascular exercises and between 40 and 70% of 1RM for strength exercises. Volume was the same for both groups: 30 min for cardiovascular exercises and 1x10 for strength exercises. Before (pre) and after (post) the intervention period and one year later (fu) a sub-maximal indirect test to estimate VO2max and a maximal indirect test to calculate 1RM were carried out. RESULTS VO2max significantly increased for both groups (p<0,05) after BWR; further increase occurred for both groups after 1 year, p=ns (VO2max: MI, pre 22,7±7,2 post 25,5±6,1 fu 27,3±7,6 ml/kg/min; HI, pre 25,6±8,8 post 28,4±10,4 fu 30,4±10,8 ml/kg/min). At short-term 1RM significantly increased for both groups (∆%, Leg press MI +37.1, HI +44.7; Chest press MI +39.6, HI +34.3; Vertical traction MI +31.9, HI +41; p<0,001), followed by a decrease after one year (∆%, Leg press MI -6.8, HI -23.6; Chest press MI -6.6, HI -19.6; Vertical traction MI -9.6, HI -12.6), which resulted to be statistically significant only for HI (p<0,01). No significant differences were detected between groups. CONCLUSION This study shows that the intensity of exercise (MI or HI) doesn t affect the magnitude of change in cardiorespiratory fitness and muscular strength. These results underline the importance of a PA to maintain elevated values of physical fitness over time. In fact, more than 60 min per week of recreation or work requiring modest PA, reported by the subjects, allow to enhance only VO2max, while maximal strength decreased because no specific training session was performed.