Fatigue induced by cross-country skiing KO sprint

A study analyzes whether the KO sprint simulation induced a phenomenon of fatigue of upper and lower limbs, and if there was any fatigue, to determine the origin. Changes in performance, lactate concentration, knee-extensor strength, and upper-limb power revealed that the KO sprint test led the skiers to a state of fatigue while on the lower-limb muscles, the decrease of knee-extensor strength was exclusively caused by peripheral fatigue, which was at least in part attributable to a failure of the excitation-contraction coupling.