Impact of Water and Land-Based Exercise Training on Risk Factors and Vascular Function in Middle-Aged and Older Men and Women

INTRODUCTION: Exercise improves vascular function, but it is unclear whether benefits are mediated by traditional cardiovascular (CV) risk factors, or whether sex differences in training effects exist in older adults. We hypothesized that exercise would improve CV risk factors, that males and females would benefit similarly, and that improvements in risk factors would correlate with changes in vascular function.

METHODS: Seventy-two healthy middle-aged/older adults (age = 62 ± 7, 26%♂) were randomized to a land-walking (LW, n = 23), water-walking (WW, n = 25) or a non-exercise control group (C, n = 23). The exercise groups undertook supervised and monitored training 3 times/week for 50 min per session, across 24 weeks. Blood pressure, body composition (DXA), blood lipids and glucose, and flow mediated brachial artery dilation (FMD) were assessed in all participants at weeks 0 and 24. To maximize power for sex differences and correlation analyses, we pooled the training groups (LW + WW).

RESULTS: Training prevented increases in LDL and TC:HDL ratio observed in C group. No group x time interactions were observed for other risk factors. Sex differences in training effects existed for visceral fat (-187 ± 189 g♂ vs -15 ± 161 g♀; P = 0.006), and lean mass (-352 ± 1045 g♂ vs 601 ± 1178 g♀; P = 0.008). Improvement in FMD was correlated with decreased waist girth (r = -0.450, P = 0.036), but not with other risk factors.

CONCLUSIONS: Exercise training prevented deterioration in lipid levels, whilst sex differences existed for body composition changes with training. Improvement in vascular function was not dependent on changes in risk factors in middle-aged/older adults, suggesting that artery health may be dependent upon other exercise-related stimuli.