Effect of race distance on performance fatigability in male trail and ultra‐trail runners

The etiology of changes in lower-limb neuromuscular function, especially to the central nervous system, may be affected by exercise duration. Direct evidence is lacking as few studies have directly compared different race distances. This study aimed investigate deficits function following short versus long trail-running races. Thirty-two male trail runners completed one five races LONG (>100 km) or SHORT (<60 km). Pre- and post-race, maximal voluntary contraction (MVC) torque evoked responses electrical nerve stimulation during MVCs at rest were used assess activation muscle contractile properties knee-extensor (KE) plantar-flexor (PF) muscles. Transcranial magnetic (TMS) was corticospinal excitability submaximal KE contractions. Race distance correlated with MVC (ρ = −0.556) twitch −0.521) decreases (p ≤ .003). decreased more (−28 ± 14%) than (−14 10%, p .005); however, time × interaction not significant .073). No differences between for PF observed. Maximal similarly both groups ≥ .637). TMS-elicited silent period .021) but .912). Greater property impairment longer races, perturbations, contributed correlation loss distance. Conversely, fatigability unaffected