Training-induced Improvement In Aerobic Fitness Inversely Associates With Changes In POMS Confusion Among Postmenopausal Women

The age-related decline in peak aerobic capacity (V̇O2peak) and concurrent rise in oxygen cost of walking narrows the physiologic reserve - predisposing postmenopausal women to mood disturbance. PURPOSE: Secondary analyses were performed to explore whether exercise training-induced improvement in markers of aerobic fitness associate with changes in mood disturbance among postmenopausal women. METHODS: Postmenopausal women (65 ± 5 y; 30.9 ± 3.6 kg/m2) who completed 8 weeks of supervised, circuit-based training were evaluated. For proof-of-concept, participants who were initially randomized to either a pre-workout beetroot juice group or an exercise-only group were pooled (n = 24) to focus on associations among changes (Δ) (i.e., between baseline and post-training) in markers of aerobic fitness. V̇O2peak was estimated from a 6-minute walk test with heart rate recovery recorded 1-minute post walk (HRR1). A fixed-workload treadmill task coupled with indirect calorimetry was used to measure steady-state oxygen uptake (V̇O2). The Profile of Mood States (POMS) questionnaire was used to measure mood disturbance. Time-point differences were evaluated with dependent samples T-test. Effect sizes were expressed as Cohen’s d. Bivariate correlations and regression modeling were used to evaluate associations of interest. RESULTS: Significant training-induced improvements were detected for ΔV̇O2peak (0.9 ± 1.2 mL/kg/min; p = 0.001, d = 0.76) and ΔHRR1 (-4 ± 9 bpm; p = 0.05, d = 0.43). No differences were found for ΔV̇O2 (-0.3 ± 2.2 mL/kg/min; p = 0.56, d = 0.12) or ΔPOMS scores (all p-values >0.05). However, multiple markers of aerobic fitness including ΔV̇O2peak (r = -0.489, p = 0.015), ΔHRR1 (r = -0.415, p = 0.049) and ΔV̇O2 (r = -0.414, p = 0.050) were significantly associated with ΔPOMS Confusion subscale. Regression modeling revealed ΔV̇O2peak and ΔHRR1 jointly accounted for 51% (R = 0.712, p < 0.001) of the variance in ΔPOMS Confusion. CONCLUSIONS: These preliminary data suggest the POMS Confusion subscale is responsive to training-induced improvements in aerobic fitness. Exercise interventions focused on increasing V̇O2peak and HRR1 may attenuate mood disturbance in postmenopausal women. Supported by: Supported by the Indiana Clinical and Translational Sciences Institute funded in part by grant number UL1TR002529 from the NIH-NCATS.