Discussion
TMD, improves mood status, fatigue, depressive, mood disorder, malnutrition, depression
MALNUTRITION
This study investigated the combined effects of LTP ingestion and PA interventions on fatigue status. There were no dropouts and all randomized participants completed the study. Supplement compliance was considerably higher in all groups (> 95%). The time spent on PA was evaluated as > 95% of the data in the study period, and the MVPA time in the placebo + PA and LTP + PA groups was significantly higher during the intervention period than at baseline. Therefore, the intervention was appropriately implemented. In this study, no significant interactions or main effects of LTP ingestion and PA intervention were observed on any of the fatigue scales. In contrast, the PA intervention improved TMD and BDI-II scores. After post-hoc paired comparisons, a significant difference was noted in the change in TMD and BDI-II scores between the LTP and LTP + PA groups, whereas no difference was found between the placebo and placebo + PA groups. These results suggest that PA intervention improves mood status and depressive symptoms, and that LTP ingestion may enhance its effectiveness.In recent years, patient-reported outcomes have been emphasized to facilitate the transition from normal to successful agingBoth psychological and physiological mechanisms, such as the distraction and monoamine hypotheses, have been shown to have beneficial effects on mood and emotional well-beingAnalyses of the main effects showed that the PA intervention significantly decreased TMD and BDI-II scores. However, there was no significant association between changes in MVPA time and changes in TMD or BDI-II scores. There may be a ceiling effect on the ability of increased MVPA to improve mood status and depressive symptoms. Among the previous studies that have investigated the effects of PA interventions on fatigue and mood status, none have assessed SB, LPA, and MVPA times during the intervention period as continuously as this study didSeveral studies have shown that middle-aged and older adults are more likely to suffer from malnutrition and depression, both of which can have negative consequences on overall health and well-beingIn the present study, there were no changes in any of the fatigue scales before or after the intervention. We used a self-report questionnaire to assess the fatigue status. Objective measures of fatigue status, such as blood and salivary biomarkers, may also require assessmentThe time spent in MVPA significantly increased in the placebo + PA and LTP + PA groups during the intervention period. In the post-hoc test, MVPA time was significantly higher in the LTP + PA group than in the placebo group from weeks 1 to 8. In contrast, at weeks 6–7, MVPA time was higher in the placebo + PA group than in the placebo group. Furthermore, MVPA time in the LTP group did not differ from that in the placebo + PA group during the entire study period. A previous study suggested that mood disorder scores are lower in active than in inactive older womenSB is defined as any waking behavior with an energy expenditure ≤ 1.5 metabolic equivalents (METs) while sitting, reclining, or lyingA previous study reported that LTP inhibits angiotensin-converting enzymesThis study has several strengths. First, this was a randomized controlled trial that assessed the combined effects of LTP ingestion and PA intervention. Second, a double-blind placebo-controlled design was used to test the effects of LTP ingestion. Finally, supplement compliance and time-related changes in PA were evaluated in detail. However, this study has several limitations. First, the number of male participants was relatively small. Second, two participants were taking angiotensin II receptor blockers, which violated the inclusion criteria. Third, although the participants were of a relatively broad age range, it was not possible to stratify and randomize them by age. Fourth, it is possible that responding to the questionnaires induced fatigue because the participants were asked to complete multiple questionnaires in a single day following an overnight fast of more than 12 h. Fifth, a control group that did not participate in either the supplement or PA intervention could have expanded the interpretation of this study. Finally, as this study was an exploratory randomized controlled trial with a small sample size, further confirmatory trials should be conducted in the future.This study suggests that eight weeks of LTP ingestion and PA intervention did not have a significant effect on fatigue status. However, PA interventions improve mood status and depressive symptoms, and the ingestion of LTP may enhance their effectiveness. Our findings may contribute to the establishment of intervention programs to address psychological problems in middle-aged and older adults.