Cardiorespiratory responses during aquatic treadmill exercise and land treadmill exercise in older adults with type 2 diabetes

BACKGROUND: The purpose of this study was to compare the effect of aquatic treadmill exercise (ATM) to land treadmill exercise (LTM) in adults with and without type 2 diabetes (T2D). METHODS: Five participants with T2D (4 females. 1 male; age=51 +/- 3 years; height=170 +/- 3 cm; weight=96 +/- 11 kg; body fat=32 +/- 1%) and five participants without T2D (4 females, 1 male: age=51 +/- 3 years; height=170 +/- 3 cm; weight=71 +/- 15 kg; body fat-27 +/- 2%) completed the study. Participants completed three. 5-minute stages of exercise at 3.2 km/h, 4.8 km/h and 6.4 km/h with 0% grade on land and aquatic treadmills. Heart rate (HR), systolic and diastolic blood pressure (SBP and DBP), absolute and relative oxygen consumption (VO2), and energy expenditure were measured at rest and during steady-state exercise at each intensity. A 2x2x4 Mixed Factorial ANOVA and Bonferroni post-hoc test with a significance level of 0.05 was used. RESULTS: All variables increased as speed increased (P<0.05) independent of group or mode. The HR value was higher on the LTM versus the ATM independent of group and treadmill stage (P=0.002) and SBP was higher in the T2D group versus no T2D independent of treadmill mode and stage (P-0.01). Relative VO2 was higher in the group without T2D compared to the T2D group at 6.4 km/h independent of treadmill mode (P=0.032). CONCLUSIONS: Although there is some evidence for the varying effects of aquatic and land exercise when comparing those with and without T2D, cardiorespiratory and metabolic variables are similar in both groups during locomotion on land and in an aquatic environment.