Vascular adaptations to 8 weeks of different types of cycling in healthy older adults.

Participants will be randomly assigned to one of three 8 week training interventions. All training sessions will be completed at the Murdoch University Exercise Physiology laboratories and will last approximately 40-75 minutes per session (depending on group allocation). Irrespective of the participant’s group allocation, all exercise sessions will be conducted with groups of up to six participants on a cycle ergometer (WattBike Pro or Trainer, Wattbike Australia, AUS). All exercise intensities will be prescribed according to a predetermined level of perceived exertion, using the Borg 6-20 rating of perceived exertion (RPE) scale, which is associated with a desired percent of aerobic capacity (VO2peak). Each session will begin and end with a 5 minute double-leg cycling based warm-up (intensity; RPE 11-13, 40-60% VO2peak) and cool down (intensity; RPE 8-10, 20-40% VO2peak). The moderate intensity double-leg continuous group will cycle continuously for 40 minutes at an RPE 11-13 (40-60% VO2peak) using normal double-leg cycling. The high intensity double-leg interval cycling group will complete twenty 30 second double-leg efforts at an RPE 15-17 (60-85% VO2peak) with each effort separated by 60 seconds of passive rest (RPE 6; <20% VO2peak). The high intensity single-leg interval cycling group will complete twenty 30 second single-leg efforts at an RPE of 15-17 with each effort separated by 60 seconds of passive rest (RPE 6). At the completion of the first twenty efforts, a short break will be provided (~5 minutes) prior to the participants completing another twenty efforts with the opposite leg. 3 sessions per week will be prescribed and monitored by Miss Nicole Gordon, an ESSA Accredited Exercise Physiologist. Program adherence will be monitored through exercise logs.