A monetary reward prolongs cycling time-to-task failure without altering performance fatigability and perceptual responses

This study aimed to determine the effects of an unexpected monetary reward on time-to-task failure (TTF) and on measures of performance and perceptual fatigability in healthy young adults. During two separate sessions, 18 participants (9 females) completed a TTF within the heavy-intensity domain (HVYTTF), which was followed, after 1 min of rest, by a TTF within the extreme-intensity domain (EXTTTF). In the second HVYTTF session, an unexpected monetary reward was offered prior the self-anticipated task failure. Before and after each trial, neuromuscular fatigue was assessed at baseline (NMFBSLN) and following HVYTTF (NMFHVY) and EXTTTF (NMFEXT) using femoral nerve stimulation during and after a quadriceps muscle isometric maximal voluntary contraction (IMVC). The unexpected monetary reward significantly increased HVYTTF (46 +/- 16 min vs. 53 +/- 22 min; P = 0.011), while reducing the following EXTTTF (68 +/- 17 s vs. 57 +/- 17 s; P = 0.034). IMVC (similar to-31%), Db(10) (similar to-42%), Db(100) (similar to-21%), low-frequency fatigue (similar to-26%), and potentiated twitch force (similar to-37%) were all reduced from NMFBSLN to NMFHVY (P < 0.001) with no further declines following NMFEXT (P > 0.005) except for Db(10) (similar to-9%, P = 0.007) and potentiated twitch force (similar to-9%; P < 0.001). Voluntary activation did not change from NMFBSLN to NMFHVY or from NMFBSLN to NMFEXT following either of the conditions (P > 0.005). These findings indicate that an unexpected monetary reward can increase exercise performance within the heavy-intensity domain. This improvement while being associated with no further reductions in neuromuscular indices of fatigue, it impaired subsequent extreme-intensity performance.