Cooling glabrous skin also known as hairless skin (areas like palms, soles, face, and ears)- helps to reduce heart rate by enhancing heat loss through specialized vascular structures called (AVAs)arteriovenous anastomoses, which act as efficient heat exchangers between the core blood and the environment.
- Cooling your glabrous skin like palms reduces heart rate: The palms contain specialized blood vessels (arteriovenous anastomoses) that facilitate heat exchange. Cooling the hands lowers core temperature and reduces cardiovascular strain reducing your heart rate.
- Autonomic modulation: Hand cooling can increase parasympathetic activity and/or reduce sympathetic drive, causing heart rate reduction.
- Metabolic and cardiorespiratory effects: Studies show hand cooling during exercise lowers heart rate and metabolic demand, helping with cardiovascular efficiency and endurance.
Here’s how it works ↓
- Heat dissipation via blood flow: Glabrous skin contains AVAs that can rapidly dilate to increase blood flow, allowing warm blood from the core to release heat to the environment. Cooling these areas lowers core body temperature in turn reducing thermal stress on the cardiovascular system.
- Reduced cardiovascular strain: Lower core temperature means the body doesn’t need to pump as much blood to the skin for cooling, leaving more blood available for muscles and vital organs. This decreases heart rate because the heart works less hard to maintain blood flow and regulate your temperature.
- Autonomic nervous system response: Cooling the face and hands can activate parasympathetic (vagal) activity and reduce sympathetic drive, causing your transient heart rate to decrease.
- Efficient heat transfer: blood cooled in glabrous skin returns directly to the heart, it rapidly lowers blood temperature, which reduces heart rate more effectively.
In summary, cooling glabrous skin improves heat loss efficiency, lowers core temperature, reduces cardiovascular workload, and activates autonomic pathways that collectively contribute to lowering heart rate during heat stress or exercise recovery.