Acute effect of induced asymmetrical running technique on foot skin temperature

The aim of the study was to evaluate skin temperature of the soles of the feet before and after a provoked asymmetrical running. Seventeen recreational male runners performed two 15 min running tests in the same session. In the first test, participants performed running without modifying their running technique (control condition). In the second running test, they repeated the same protocol using an ankle weight of 1.5 kg in the non-dominant ankle (asymmetrical condition). Rate of perceive exertion, heart rate and spatio-temporal parameters were measured during the running tests. Skin temperature was measured with an infrared camera before and after each condition. Generally, comparing both lower limbs, non-preferred limb (with the ankle weight) had lower contact time (p < 0.001 and ES > 0.8), higher stride length (p < 0.05 and ES > 0.3) and higher stride frequency in asymmetrical condition (p < 0.01 and ES > 0.4). However, no differences were observed on skin temperature between both feet in the two conditions in any of the regions of interest assessed (p > 0.05). Although the asymmetry generation model used provoked technical asymmetries in spatio-temporal parameters during running, no thermal asymmetries were observed between preferred and non-preferred sole of the foot. These results suggested the lower importance of mechanical than physiological mechanisms on skin temperature during running.