Effect of food intake on the ventilatory response to increasing core temperature during exercise.
Level 3 - non-randomized controlled study
Small controlled crossover physiological study; randomization of session order is not specified in the abstract
PubMed 29944847 · doi:10.1139/apnm-2018-0069
What was done
Nine healthy male subjects performed cycle ergometer exercise at 50% of peak oxygen uptake under two conditions: with and without prior food intake. Ventilatory sensitivity to rising core temperature was determined using slopes of regression lines relating ventilatory parameters to core temperature. Outcomes included esophageal temperature, mean skin temperature, mean body temperature, oxygen uptake, carbon dioxide elimination, minute ventilation, alveolar ventilation, tidal volume, and end-tidal carbon dioxide pressure.
What was found
The abstract reports no numerical values, effect sizes, or p-values. Food intake significantly increased baseline mean skin temperature, mean body temperature, oxygen uptake, carbon dioxide elimination, minute ventilation, alveolar ventilation, and tidal volume. During exercise, esophageal temperature, mean skin temperature, mean body temperature, carbon dioxide elimination, and end-tidal carbon dioxide pressure were all significantly higher with food intake than without. However, ventilatory parameters and ventilatory sensitivities to rising core temperature during exercise did not differ between conditions, except for higher tidal volume during the first 5 minutes of exercise.
Why it matters
It demonstrates that the metabolic and thermic load of prior feeding does not meaningfully alter the ventilatory response to rising core body temperature during moderate-intensity cycling in healthy men.
Limits
The sample size is very small (n = 9) and includes only healthy men. The abstract does not specify whether condition order was randomized, does not provide meal timing or composition, and reports no numerical data or measures of variance.
Cited by
- supports Food intake elevates core body temperature via diet-induced thermogenesis.