Research: surface temperature of covered legs during and after exercise

Krishona Martinson
University of Minnesota Extension
Ag News

Boots and leg wraps are commonly used to protect the lower legs of the horse from trauma during exercise.

However, previous research suggests they can result in increased leg temperature that may be detrimental to underlying tendons. This study, conducted at Middle Tennessee State University, was designed to explore lower leg surface temperature during and after exercise when common leg protections were applied. 

Six clinically-sound, mature horses were used to test six boots or wraps: a neoprene boot, a perforated neoprene boot, an alternative neoprene boot, a cross country boot, a combination fleece and elastic wrap and a polo wrap.

The covered leg was selected randomly and the other leg served as a bare leg control. A data logger recorded temperature and humidity every minute during a 20 minute exercise test and for 180 minutes post-exercise (e.g. recovery) during moderate  conditions (73 degrees Fahrenheit; 53% humidity). 

The bare leg temperature was lowest (82 degrees Fahrenheit), then peaked and plateaued (91 degrees Fahrenheit) during recovery. Conversely, covered legs increased during exercise from 90 degrees Fahrenheit (minute zero) to 97 degrees Fahrenheit at minute 15, then plateaued during recovery. The polo wrap was hotter and more humid than all other covered legs. All covered legs failed to return to baseline temperature and humidity after 180 minutes post-exercise. 

The results support the thought that convection cooling is impaired by boots and wraps during exercise and suggests covered legs may reach damaging temperatures.

Interestingly, no covered or bare leg returned to baseline temperature within 180 minutes, necessitating further research into the time required for passive cooling of the equine lower leg during exercise and recovery.