Acute cardiopulmonary responses to different intensities of exercise in healthy older adults

Abstract

The overall purpose of this thesis was to study the acute cardiopulmonary responses to different intensities of exercise in healthy older adults. Thirty healthy older males and females (69.6 ǂ 6.2 yrs.; males n = 15) underwent maximal exercise testing to determine maximal oxygen consumption (VO2MAX) and peak power output (PPO), and completed each of the following exercise protocols in a randomized crossover design: high intensity interval exercise (HI; 1 minute 90% PPO followed by 1 minute 10% PPO, x10), continuous moderate intensity exercise (MOD; 20 minutes at 50% PPO), and sprint intensity interval exercise (SPRT; 20 second “all-out” sprints followed by 2 minutes of 50W, x3). Oxygen consumption (VO2), ventilation (VE), tidal volume (Vt), respiratory rate (RR), heart rate (HR), tissue saturation index (TSI) of the vastus lateralis and rated perceived exertion (RPE) were monitored during exercise sessions. Heart rate recovery (HRREC) was assessed after each exercise session and heart rate variability (HRV) was compared using resting and post-exercise values. Overall, it was found that high fit individuals attained the greatest VO2 peak during MAX while low fit females attained a larger VO2 peak during SPRT compared to MAX. The rate of HRREC was greatest in high fit males. These findings have important implications for the individualization of exercise prescription, Future research will need to compare the three different types of exercise training to determine which protocol leads to larger adaptations in older adults.