Objective and subjective measures of exercise intensity during thermo-neutral and hot yoga
Publication: Applied Physiology, Nutrition, and Metabolism • 23 November 2017 • https://doi.org/10.1139/apnm-2017-0495
Abstract
While hot yoga has gained enormous popularity in recent years, owing in part to increased environmental challenge associated with exercise in the heat, it is not clear whether hot yoga is more vigorous than thermo-neutral yoga. Therefore, the aim of this study was to determine objective and subjective measures of exercise intensity during constant intensity yoga in a hot and thermo-neutral environment. Using a randomized, crossover design, 14 participants completed 2 identical ∼20-min yoga sessions in a hot (35.3 ± 0.8 °C; humidity: 20.5% ± 1.4%) and thermo-neutral (22.1 ± 0.2 °C; humidity: 27.8% ± 1.6%) environment. Oxygen consumption and heart rate (HR) were recorded as objective measures (percentage of maximal oxygen consumption and percentage of maximal HR (%HRmax)) and rating of perceived exertion (RPE) was recorded as a subjective measure of exercise intensity. There was no difference in exercise intensity based on percentage of maximal oxygen consumption during hot versus thermo-neutral yoga (30.9% ± 2.3% vs. 30.5% ± 1.8%, p = 0.68). However, exercise intensity was significantly higher during hot versus thermo-neutral yoga based on %HRmax (67.0% ± 2.3% vs. 60.8% ± 1.9%, p = 0.01) and RPE (12 ± 1 vs. 11 ± 1, p = 0.04). According to established exercise intensities, hot yoga was classified as light-intensity exercise based on percentage of maximal oxygen consumption but moderate-intensity exercise based on %HRmax and RPE while thermo-neutral yoga was classified as light-intensity exercise based on percentage of maximal oxygen uptake, %HRmax, and RPE. Despite the added hemodynamic stress and perception that yoga is more strenuous in a hot environment, we observed similar oxygen consumption during hot versus thermo-neutral yoga, classifying both exercise modalities as light-intensity exercise.
Résumé
Le yoga en salle chauffée est devenu très populaire au cours des dernières années, et ce, à cause, en partie, du plus grand défi environnemental associé à l’exercice dans la chaleur, mais il n’est pas bien établi si le yoga en salle chauffée demande plus de vigueur que le yoga thermoneutre. En conséquence, cette étude se propose de présenter des mesures objectives et subjectives de l’intensité d’exercice au cours d’une séance de yoga d’intensité constante en salle chauffée et dans un environnement thermoneutre. Selon un devis croisé aléatoire, 14 participants se soumettent à deux séances identiques de 20 min de yoga en salle chauffée (35,3 ± 0,8 °C; humidité: 20,5 ± 1,4 %) et dans un local thermoneutre (22,1 ± 0,2 °C; humidité: 27,8 ± 1,6 %). La consommation d’oxygène et la fréquence cardiaque (« HR ») constituent les mesures objectives (pourcentage de la consommation maximale d’oxygène et pourcentage de HR (« % HRmax ») et la perception de l’intensité de l’effort (« RPE ») constitue la mesure subjective. À la lumière du pourcentage de la consommation maximale d’oxygène, on ne note pas de différence d’intensité d’effort entre la salle chauffée et le local thermoneutre (30,9 ± 2,3 vs 30,5 ± 1,8 %, p = 0,68). Toutefois, à la lumière de % HRmax et de RPE, l’intensité d’exercice est plus élevée en salle chauffée que dans le local thermoneutre (67,0 ± 2,3 vs 60,8 ± 1,9 %, p = 0,01 et 12 ± 1 vs 11 ± 1, p = 0,04 respectivement). D’après les normes d’intensité d’exercice, la séance de yoga en salle chauffée se situe à intensité légère en se basant sur le pourcentage de la consommation maximale d’oxygène, mais à intensité modérée en fonction du % HRmax et de RPE; d’autre part, la séance de yoga dans un local thermoneutre se situe à intensité légère à la lumière du pourcentage de la consommation maximale d’oxygène, du % HRmax et de RPE. Nonobstant l’augmentation de la contrainte hémodynamique et de la perception selon laquelle la séance de yoga est plus exigeante en salle chauffée, nous enregistrons des consommations d’oxygène similaires dans les deux conditions, ce qui situe les séances dans ces deux conditions à « intensité légère ». [Traduit par la Rédaction]
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Information & Authors
Information
Published In
Applied Physiology, Nutrition, and Metabolism
Volume 43 • Number 4 • 2018
Pages: 397 - 402
History
Received: 1 August 2017
Accepted: 11 November 2017
Published online: 23 November 2017
Copyright
©2018