Rating of Perceived Exertion: A Large Cross-Sectional Study Defining Intensity Levels for Individual Physical...

Area of Science:

• Exercise Physiology
• Sports Science
• Clinical Practice

Background:

• Physical inactivity is a global health concern, necessitating effective strategies for promoting sports participation.
• Accurate training intensity prescription is crucial for physical activity recommendations.
• Cardiopulmonary exercise testing (CPX) precisely determines training intensities but lacks broad accessibility.

Purpose of the Study:

• To determine Rating of Perceived Exertion (RPE) values at the individual anaerobic threshold (LT2) and specific blood lactate (bLa) concentrations in a large cohort.
• To evaluate the influence of individual factors on RPE using multivariable analysis.
• To establish a more personalized approach to exercise intensity prescription using the Borg scale.

Main Methods:

• Analysis of CPX data from 6311 participants using bicycle or treadmill ergometry.
• Estimation of RPE values at defined bLa concentrations (2, 3, 4 mmol/l) and LT2 via spline interpolation.
• Application of multivariable cumulative ordinal regression to assess the impact of sex, age, ergometry type, VO2max, and exercise duration on RPE.

Main Results:

• Median RPE values were 13 at 2 mmol/l, 15 at 3 mmol/l, 16 at 4 mmol/l, and 15 at LT2 for the total population.
• Individual factors like sex, age, ergometry type, VO2max, and number of stages significantly influenced RPE, particularly at lower intensities.
• The number of stages was the sole factor consistently influencing RPE across all measured lactate concentrations and LT2.

Conclusions:

• Proposed RPE ranges for exercise intensity: ≤11 (light), 12-14 (moderate), 15-17 (vigorous), with RPE 15 distinguishing heavy and severe domains.
• These RPE recommendations slightly differ from current American College of Sports Medicine (ACSM) guidelines.
• The study advocates for considering individual factors (age, sex, fitness, etc.) for personalized RPE-based exercise prescription, especially for endurance activities.