Research

Mixed

Extreme mountain ultra-marathons (approx. 166 km with significant elevation change) cause severe neuromuscular fatigue, including both central and peripheral components, with full recovery of maximal force capacity occurring within 9 to 16 days.

After completing an extreme mountain ultra-marathon (like the UTMB), expect significant muscle weakness and fatigue. Do not rush back into intense training. Most recovery happens within the first 9 days, but full neuromuscular function may take up to 16 days. Prioritize rest and light activity during this period.

GoodSupportsHIGH confidence
Sixteen days after MUM, NMF had returned to initial values, with most of the recovery process occurring within 9 days of the race.
Guillaume Y. Millet et al. · PLoS ONE · 2011

Why this rating

Well-controlled study with experienced subjects, clear metrics, and statistical significance, though limited to a specific extreme event.

Source

Neuromuscular Consequences of an Extreme Mountain Ultra-Marathon

Guillaume Y. Millet et al. · PLoS ONE · 2011

DOI 10.1371/journal.pone.0017059

cohort · n=22Cited 248×
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DOI resolved against Crossref · corpus check 2026-06-10

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