The Absolute and Relative Reliability of Psychophysiological Responses to Self-Selected Exercise Intensity in Elderly Women

ABSTRACT

Background: Self-selected exercise intensity (SSEI) promotes higher affect (pleasure) during exercise, but its reliability is still unclear. Purpose: to evaluate the test-retest reliability and the minimum detectable change of the perceptive and physiological responses in two sessions of SSEI on treadmill in elderly women. Method: Twenty elderly women (ages 65.3 ± 4.2 years) performed two 20-min laboratory-based treadmill aerobic exercise sessions with self-selected intensity. During the sessions, %VO_2max, %HR_reserve, affect, and rating of perceived exertion (RPE) were recorded. Reliability was calculated using the intraclass correction coefficient (ICC) and Bland–Altman plots. The minimum detectable change (MDC) was also calculated. Results: ICC values were 0.98 for % VO_2max, 0.83 for % HR_reserve, 0.85 for affect, and 0.80 for RPE. No differences were observed in mean values between sessions for all the variables. MDCs were lower than 0.7% for VO_2max, 11.7% for HR_reserve, 0.7 for affect, and 0.8 for RPE. Bland–Altman plots showed a bias of 0.50% for HR_reserve, 3.2% for VO_2max, 0.05 for affect, and −0.35 for RPE. Conclusion: Self-selected intensity during aerobic exercise performed on treadmill is reliable, which promotes adequate and lower MDC values on physiological and perceptual responses in elderly women.

KEYWORDS:

• Affect
• effort
• reproducibility
• aerobic exercise

Additional information

Funding

This work was supported by grants from the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – CAPES (#1/2016).