Figure 8 Recovery of threshold for stimuli of (A) 0.1 ms and (B) 1 ms duration for axons from patients with amyotrophic lateral sclerosis (ALS) and controls in the early post‐contraction period. The ratio of normalised threshold recorded during the post‐contraction period compared with the maximal change in threshold immediately following the period of contraction was used as an index of threshold recovery (NT/max). The ratio shows a similar relationship between recovery of threshold for axons from patients with ALS and controls, suggesting that Na⁺/K⁺ pump function remains unaffected in patients with ALS.