Blood pressure responses of sedentary African American women during cycle and treadmill exercise

Objective: To examine blood pressure (BP) insedentary African American women during two exercise intensities on a cycle and treadmill at fixed heart rate (HR) values. Methods: Blood pressure (BP) and heart rate (HR) were assessed in 44 women (age 33.1 +/- 8.2 years) during cycling and treadmill walking at 40% and 60% heart rate reserve (HRR). Systolic blood pressure (SBP) and diastolic blood pressure (DBP) reactivity differences were evaluated with separate 2 (mode: cycle, treadmill) X 2 (intensity: 40%, 60% HRR) repeated measures analyses of covariance. Separate multiple regression analyses for the cycle and treadmill were performed to examine potential contributors to higher SBP reactivity at 60% HRR. Results: After adjusting for baseline SBP, body mass index (BMI), and age, mean SBP reactivity was higher during cycling compared to treadmill at both levels of intensity (P:<=.05). The DBP reactivity revealed a main effect for mode (P <=.05) only with cycle DBP reactivity higher than treadmill for both intensities. Cycling significantly predicted SBP at 60% HRR (P <=.001), accounting for 66% of the variance in SBP reactivity. However, in both regression models, baseline SBP was inversely related to SBP reactivity (P <=.01). Conclusions: At fixed HR values, after adjusting for baseline BP, BMI, and age, BP reactivity is mode dependent and greater for cycling than treadmill exercise at both low and moderate exercise intensity. Baseline SBP is inversely related to the magnitude of SBP reactivity after controlling for the effects of BMI and age.