Trait Mental And Physical Fatigue Impact Biomarkers And Performance Outcomes After A Fatiguing Protocol

Evidence suggests that there is heterogeneity in biomarker and performance outcomes to various fatiguing protocols. Previously, our lab identified trait mental and physical energy and fatigue (TME, TMF, TPE, TPF) as factors that contribute to explaining these heterogenous responses to mentally fatiguing protocols. However, these studies did not assess changes in performance after a physically fatiguing protocol. PURPOSE: This study investigated the relationship between trait moods and directionality of change in performance outcomes after a 60-minute physically fatiguing protocol. METHODS: Ten participants (6 male, 4 female) completed a multi-day protocol where baseline measures of TME, TMF, TPE, TPF were assessed on the first day. The following day participants saliva were collected in addition to a series of performance measures including the countermovement jump (CMJ), maximum hand-release push-ups, isometric mid-thigh pulls, plyometric pushups, maximum plan and a maximum 60s cycling were collected prior to and after a 60-minute fatiguing protocol simulating military training. Results of the performance measures were bifurcated into improved and declined. A series of Wilcoxon Sign Rank test were used to assess differences trait moods between the bifurcated outcomes. RESULTS: Findings suggest that individuals who were high TMF (>6) had an increase in cortisol (U = 85, p = 0.02) and a decrease in uric acid (U = 36, p = 0.04) post-fatiguing session. Interestingly, individuals with high TPF (>6) (U = 1.5, p = 0.02) and high TMF (>6) (U = 2, p = 0.03) had an increase in the duration of the eccentric phase of the CMJ. There were no significant differences between directionality of change between other outcomes and TME, TPE, TMF, and TPF. CONCLUSIONS: Findings from this exploratory study suggest that individuals who are normally mentally and physically fatigued may respond more negatively to a 60-minute physically fatiguing protocol. These findings differ compared to those in mentally fatiguing protocols, where individuals with low TMF and TPF perform poorly after the completion of the mentally fatiguing interventions. Our findings support further exploring the role of trait level moods at modifying responses to various fatiguing interventions.