Human thermal responses during leg-only exercise in cold water

Area of Science:

• Physiology
• Environmental Medicine
• Exercise Science

Background:

• Previous studies indicated whole-body exercise accelerates core temperature fall during cold water immersion.
• The specific impact of exercise type on thermoregulation in cold water remains less understood.

Purpose of the Study:

• To investigate the effect of leg exercise on core temperature during cold water immersion.
• To compare thermoregulatory responses between leg exercise and static immersion.

Main Methods:

• Fifteen subjects underwent 40-minute head-out immersion in 15°C water.
• Subjects performed leg exercise during one immersion condition and static immersion during another.
• Aural and rectal temperatures were monitored to assess core temperature changes.

Main Results:

• Core temperature (aural and rectal) fell by greater amounts during static immersion compared to leg exercise immersion.
• Leg exercise did not accelerate the rate of core temperature fall.

Conclusions:

• The type of exercise performed is a significant factor influencing core temperature changes during cold water immersion.
• Leg exercise may attenuate the rate of core temperature decline compared to static immersion.