Our body has a heat regulation system that prevents us from overheating during a workout or on a hot summer day. But who sweats more: men or women? A study assesses gender differences in the body’s response to heat.
Research shows that sweating may not depend on gender, but on the ratio of surface area to body mass. Have you ever wondered why you sweat during a good workout? The human body has an internal heat-regulating system that some have compared to a furnace: it produces heat and then releases it through various physiological processes. One of them is sweating.
Our normal body temperature varies between 36.5 and 37.5°C. When the outside temperature rises, it sends signals to the hypothalamus, sometimes called the body’s thermostat. The hypothalamus responds to temperature changes by making physiological adjustments to maintain this ideal internal temperature.
On a hot summer day, or during an intense session at the gym, temperature receptors in our skin send signals to the hypothalamus, which in turn “tells” the body to start cooling down by producing sweat. . Until now, men and women were thought to react differently to rising heat due to gender-related physical characteristics. But research by scientists from the University of Wollongong in Australia and the Mie Prefectural College of Nursing in Japan challenges this misconception.
The researchers hypothesized that the thermal response would change based on the ratio of body surface area to mass, not gender. A secondary hypothesis was that tall individuals would sweat more to adapt to the increasing heat. The results were published in the journal Experimental Physiology.
Sweating: Gender Doesn’t Matter, But Body Size Does
The study assessed the vasomotor and sudomotor functions of 60 healthy participants of varying sizes and shapes in 36 men and 24 women. Participants performed two tasks under compensatory conditions of 28°C and 36% relative humidity. They rested for 20 minutes, then cycled at a steady heat-producing pace for 45 minutes. Participants also cycled at a higher intensity.
Under these conditions, the body naturally tries to keep the body temperature from rising by sweating and increasing blood flow to the skin. The researchers assessed forearm blood flow and body vascular conductance.
The trials revealed that the specific surface area of the mass was indeed a significant factor that determined vasomotor and sudomotor responses in both men and women. The surface area of mass accounted for 10-48% of the individual variability in the body’s response to heat. The researchers took into account morphological differences between the sexes, but sex-related differences explained less than 5% of the changes found between individuals.
The study therefore concluded that the way our body reacts to heat depends on morphological changes, but not on sex. The same changes in body temperature occurred in all participants, regardless of gender. Additionally, the study found that women and short men, who have more surface area per kilogram of body mass, lose heat by increasing blood circulation rather than sweating. In comparison, and as the hypothesis suggested, taller people sweat more.
Does sex have an independent effect on thermoeffector responses during exercise in the heat?
Variations in body morphology explain sex differences in thermoeffector function during compensable heat stress