What is real change in submaximal cardiorespiratory fitness in older adults? Retrospective analysis of a clinical trial

Abstract

Objective: To assess the test–retest reliability of submaximal cardiorespiratory fitness in healthy active older adults. Methods: This was a retrospective analysis of 41 adults enrolled in a clinical trial [mean (sd) aged 59 yrs (7); 29% females; and body mass index 24.5 kg/m2 (3.3)]. Cardiorespiratory fitness was assessed using a cycle ergometer 6 weeks apart. The initial workload was 1 W per kilogram of free fat mass (W/kg FFM) and increased by 0.5 W/kg FFM every 3 min until participants could not maintain the speed at ≥ 60 rpm, they reached a rating of perceived exertion of 15–17, and/or obtained a respiratory exchange ratio (RER) of 1.000. Reliability of VO 2, heart rate and RER was asse..