BackgroundLow cardiorespiratory fitness is an independent predictor of all-cause and cardiovascular mortality, and interventions that increase fitness reduce risk. Water-walking decreases musculoskeletal impact and risk of falls in older individuals, but it is unclear whether water-walking improves aerobic fitness in the same way as weight-dependent land-walking. This randomized controlled trial involved 3 intervention groups—a no-exercise control group (CG), a land-walking (LW) group, and a water-walking (WW) group—to investigate the comparative impacts of LW and WW to CG on fitness.MethodsBoth exercise groups attended individually tailored, center-based, intensity-matched 3 × weekly sessions for 24 weeks, which progressed to 150 min of exercise per week. This was followed by a 24-week no-intervention period. Maximal graded exercise tests were performed on a treadmill at Weeks 0, 24, and 48.ResultsMaximal oxygen uptake increased from Week 0 to Week 24 in both exercise groups (0.57 ± 0.62 mL/kg/min, 0.03 ± 0.04 L/min for LW; 0.93 ± 0.75 mL/kg/min, 0.06 ± 0.06 L/min for WW, mean ± SE) compared to the CG (–1.75 ± 0.78 mL/kg/min, –0.16 ± 0.05 L/min) (group × time, p < 0.05). Time to exhaustion increased significantly following LW only (123.4 ± 25.5 s), which was significantly greater (p = 0.001) than the CG (24.3 ± 18.5 s). By Week 48, the training-induced adaptations in the exercise groups returned to near baseline levels.ConclusionOur study supports current physical-activity recommendations that 150 min/week of moderate-intensity exercise produces improvements in fitness in previously sedentary older individuals. Also, LW and WW elicit similar improvements in fitness if conducted at the same relative intensities. Exercise-naïve older individuals can benefit from the lower impact forces and decreased risk of falls associated with WW without compromising improvements in cardiorespiratory fitness.
Haynes, A., Naylor, L., Carter, H., Spence, A., Robey, E., Cox, K., Maslen, B., Lautenschlager, N., Ridgers, N. D., & Green, D. (2020). Land-walking vs. water-walking interventions in older adults: Effects on aerobic fitness. Journal of Sport and Health Science, 9(3), 274-282. https://doi.org/10.1016/j.jshs.2019.11.005