Variability in Submaximal Self-Paced Exercise Bouts of Different Intensity and Duration

Abstract

Purpose: Rating of perceived exertion (RPE) as a training-intensity prescription has been extensively used by athletes and coaches. However, individual variability in the physiological response to exercise prescribed using RPE has not been investigated. Methods: Twenty well-trained competitive cyclists (male = 18, female = 2, maximum oxygen consumption =55.07 [11.06] mL·kg−1·min−1) completed 3 exercise trials each consisting of 9 randomized self-paced exercise bouts of either 1, 4, or 8 minutes at RPEs of 9, 13, and 17. Within-athlete variability (WAV) and between-athletes variability (BAV) in power and physiological responses were calculated using the coefficient of variation. Total variability was calculated as the ratio of WAV to BAV. Results: Increased RPEs were associated with higher power, heart rate, work, volume of expired oxygen (VO2), volume of expired carbon dioxide (VCO2), minute ventilation (VE), deoxyhemoglobin (ΔHHb) (P < .001), and lower tissue saturation index (ΔTSI%) and ΔO2Hb (oxyhaemoglobin; P < .001). At an RPE of 9, shorter durations resulted in lower VO2 (P < .05) and decreased ΔTSI%, and the ΔHHb increased as the duration increased (P < .05). At an RPE of 13, shorter durations resulted in lower VO2, VE, and percentage of maximum oxygen consumption (P < .001), as well as higher power, heart rate, ΔHHb (P < .001), and ΔTSI% (P < .05). At an RPE of 17, power (P < .001) and ΔTSI% (P < .05) increased as duration decreased. As intensity and duration increased, WAV and BAV in power, work, heart rate, VO2, VCO2, and VE decreased, and WAV and BAV in near-infrared spectroscopy increased. Conclusions: Self-paced intensity prescriptions of high effort and long duration result in the greatest consistency on both a within- and between-athletes basis.

Validity of the Borg 6–20 categories obtegories obtained in incremental testing for prescribing aerobic exercise intensity: a systematic review

“…A total of 1434 references were found. After applying the criteria established as guiding criteria for inclusion, 15 studies were considered eligible for review [19][20][21][22][23][24][25][26][27][28][33][34][35][36][37]. the description of article selection Human Movement, Vol.…”

“…Similarly, Hartshorn and Lamb [33] tested the reproducibility of prescriptions made on a cycle ergometer with selfregulated intensities for categories 9, 13, 15, and 17, showing an intraclass correlation coefficient between 0.45 and 0.86 for O 2 in the comparison of 3 trials performed for each RPE category. confirming these findings, O'Grady et al [37] examined individual variability in physiological response to prescribed exercise with RPE categories 9, 13, and 17 of the Borg 6-20 scale and identified that prescriptions with high effort and long durations resulted in greater consistency on both an in-and inter-athlete basis.…”

“…So far, only 3 studies have investigated the reliability [34,37] and reproducibility [33,37] levels of selfregulated intensity exercise prescriptions with the Borg 6-20 scale.…”

Test–retest reliability of a 30-min fixed perceived effort cycling exercise

“…Several studies have identified that fixed perceived effort activity is reliable. For instance, O’Grady et al ( 2021 ) discerned that exercise at three separate RPE intensities was considered reliable at both the intra- and inter-individual level. Notably, the more intense the fixed effort exercise was, the more reproducible the findings were (i.e., RPE 17 demonstrated better reliability than RPE 9).…”

“…First, both fixed perceived effort intensities would be consistently reproduced. Second, based on findings by previous studies (Eston and Williams 1988 ; Cochrane-Snyman et al 2016 ; O’Grady et al 2021 ), performance (e.g., power output [W]), physiological (e.g., heart rate [HR], relative oxygen uptake [ ], minute ventilation [ ], breathing frequency [BF]), and psychological (e.g., affect, self-efficacy) variables during a higher intensity fixed effort exercise would indicate higher reliability values compared to lower intensity fixed effort exercise.…”