Women show similar central and peripheral fatigue to men after half‐marathon^*

Abstract

Women are known to be less fatigable than men in single-joint exercises, but fatigue induced by running has not been well understood. Here we investigated sex differences in central and peripheral fatigue and in rate of force development (RFD) in the knee extensors after a half-marathon run. Ten male and eight female amateur runners (aged 25-50 years) were evaluated before and immediately after a half-marathon race. Knee extensors forces were obtained under voluntary and electrically evoked isometric contractions. Maximal voluntary isometric contraction (MVC) force and peak RFD were recorded. Electrically doublet stimuli were delivered during the MVC and at rest to calculate the level of voluntary activation and the resting doublet twitch. After the race, decreases in MVC force (males: -11%, effect size [ES] 0.52; females: -11% ES 0.33), voluntary activation (males: -6%, ES 0.87; females: -4%, ES 0.72), and resting doublet twitch (males: -6%, ES 0.34; females: -8%, ES 0.30) were found to be similar between males and females. The decrease in peak RFD was found to be similar between males and females (males: -14%, ES 0.43; females: -15%, ES 0.14). Half-marathon run induced both central and peripheral fatigue, without any difference between men and women. The maximal and explosive strength loss was found similar between sexes. Together, these findings do not support the need of sex-specific training interventions to increase the tolerance to neuromuscular fatigue in half-marathoners.

Post-Exercise Hypotension and Reduced Cardiac Baroreflex after Half-Marathon Run: In Men, but Not in Women

“…While in the present study the same relative speed (≈78% of MAS) was observed in both groups, men completed the 21-km faster than women due to their higher MAS. For both groups, the observed performance was in the range of expected values for half-marathon participants of similar training levels (e.g., [ 51 ]). The longer exercise duration for women resulted in a similar weight loss (that could be used as a rough estimation of hydration status), which was in the range of typical weight loss observed with a half-marathon race [ 31 ].…”

Neuromuscular Fatigue Does Not Impair the Rate of Force Development in Ballistic Contractions of Submaximal Amplitudes

“…Shortly after the half-marathon, the maximal force decreased by ≈21%, confirming that the prolonged run induced moderate muscle fatigue in knee extensors. This is in line with our previous studies where we also found a moderate decrease (ranged 11–24%) in maximal force after half-marathons performed in similar experimental conditions ( Boccia et al, 2017a , b , 2018 ). The strength loss is a common finding after endurance running in ecological race conditions: it increases non-linearly with the duration of exercises and it may vary between 8 and 41% ( Millet and Lepers, 2004 ; Place et al, 2010 ; Giandolini et al, 2016 ).…”

“…The amount of central fatigue depends on many exercise parameters, such as intensity, duration, and contraction modality, among others ( Taylor et al, 2016 ). While a detailed discussion of the mechanisms regulating the amount of central fatigue is beyond the scope of this paper, it is evident in the literature that central fatigue is overall greater for extreme-duration running ( Millet and Lepers, 2004 ; Martin et al, 2010 ; Temesi et al, 2014 ) rather than for shorter, more intense bouts like half-marathons ( Ross et al, 2010 ; Boccia et al, 2018 ).…”

“…Consequently, a distinction should be drawn between ballistic contraction of maximal amplitudes, usually adopted in the literature to calculate the maximal RFD, and ballistic contraction of submaximal amplitudes, which are possibly more relevant for endurance running. While it has been demonstrated that running-based fatiguing protocols impair the maximal RFD ( Oliveira et al, 2013 ; Boccia et al, 2017a , 2018 ), it is unknown to what extent muscle fatigue may impair the ability to quickly produce forces of submaximal amplitudes.…”

“…However, despite the neuromuscular correlates are not clear, RFD-SF has been considered to be an appealing measure to compare individuals and populations independently to their strength ( Bellumori et al, 2011 ), since it is not affected by maximal force capacity. It is well known that both central and peripheral mechanisms contribute to impair maximal RFD after fatiguing exercise ( Buckthorpe et al, 2014 ; Boccia et al, 2016 , 2018 ; Maffiuletti et al, 2016 ), but the impact of fatigue on RFD-SF has not been yet investigated.…”