An analysis of the perceived causes leading to task-failure in resistance-exercises
Background: While reaching task-failure in resistance-exercises is a topic that attracts scientific and applied interest, the underlying reasons leading to task-failure remain underexplored. Here, we examined the reasons subjects attribute to task-failure as they performed resistance-exercises using different loads.Methods: First, twenty-two resistance-trained subjects (11-females) completed one Repetition-Maximum (RM) tests in the barbell squat and bench-press. In the next two sessions, subjects performed two sets to task-failure in both exercises, using either 70% or 83% of 1RM. Immediately after set-completion, subjects verbally reported the reasons they perceived to cause task-failure. Their answers were recorded, transcribed, and thematically analyzed. The differences between the frequencies of the identified categories were then tested using a mixed logistic regression model.Results: The most commonly reported reason was muscle fatigue (54%, p<.001), mostly of the target muscles involved in each exercise. However, remote muscles involved to a lesser extent in each exercise were also reported. Approximately half of the remaining reasons included general fatigue (26%), pain (12%), cardiovascular strain (11%), and negative affect (10%), with the latter reported more often in the squat (p=.022).Conclusions: In contrast to our expectations, task-failure was perceived to be caused by a range of limiting factors other than fatigue of the target muscles. It now remains to be established whether different perceived limiting factors of resistance-exercises lead to different adaptations, such as muscular strength and hypertrophy.