[Purpose] Humans show near-24-h physiological and behavioral rhythms, which encompass the daily cycle of sleep and wakefulness. Exercise stimulates circadian rhythms, including those of cortisol, melatonin, and core body temperature, and affects sleep quality. We systematically reviewed studies that examined the effects of exercise intensity and timing on physiological circadian rhythms and sleep quality.[Methods] In this systematic review, we used the online databases PubMed, Science Direct, Web of Science, and Embase. This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Two independent and experienced systematic reviewers performed the search and selected relevant studies. The participant, intervention, comparison, and outcome characteristics were: (1) adults; (2) exercise treatment; (3) no exercise treatment or different types of exercise (pre-exercise baseline); (4) cortisol, melatonin, or core body temperature measurement, and subjective or objective sleep quality assessments.[Results] We identified 9 relevant articles involving 201 participants (77.1% of whom were male). Our review revealed that short-term evening exercise delayed melatonin rhythm and increased nocturnal core body temperature; however, no negative effects on non-rapid eye movement sleep and sleep efficiency were observed. Moreover, no differences in sleep quality were observed between acute high-intensity and moderate-intensity exercises. With long exercise durations, the core body temperature tended to increase and return to baseline levels at 30–120 min.[Conclusion] Our review showed that short-term evening exercise and high-intensity exercise did not have a significant negative effect on sleep quality but physiological circadian rhythm tended to alter. Longterm morning exercise tended to decrease cortisol concentrations after awakening and improve sleep quality. Future studies should examine the effects of long-term exercise timing and intensity on circadian rhythm and sleep.

[Purpose] Circadian rhythms regulate key physiological and behavioral processes. Modern lifestyles, characterized by irregular schedules, artificial lighting, and late-night eating disrupt these rhythms, leading to metabolic and emotional health disturbances. Latenight eating misaligns the circadian clock, affecting neurotransmitter function, hormonal rhythms, and inflammatory pathways, thereby increasing the risk of mood disorders.[Methods] This review synthesizes findings from human and animal studies that examined the effects of late-night eating on circadian misalignment and emotional health. Studies were selected on the basis of the ir relevance to circadian disruption and mood regulation. This review categorizes the physiological mechanisms involved and evaluates dietary timing interventions, such as time-restricted eating (TRE), earlier meal timing, and meal regularity as potential strategies to mitigate these effects.[Results] Late-night eating delayed melatonin onset, elevated nocturnal cortisol levels, disrupted serotonin and dopamine rhythms, and increased systemic inflammation, contributing to emotional instability. Aligning mealtimes with the circadian rhythm improves sleep quality, neurotransmitter balance, and stress resilience. TRE and earlier meal timing show promise in mitigating these effects, although further research is needed to optimize the strategies for different chronotypes and metabolic profiles.[Conclusion] Circadian-aligned meal timing is a practical and noninvasive approach to mitigate the adverse effects of late-night eating on metabolic and emotional health. Future research should refine personalized chrononutrition interventions and assess their long-term effects on mood disorders. Implementing meal-timing strategies based on circadian science could serve as a crucial tool for improving public health and preventing diet-related emotional dysregulation.

Purpose: Preventive or therapeutic interventions are key to maintaining independence in pre-frail and/or frail elderly. Therefore, we investigated whether multi-component interventions were effective in physical fitness levels and vascular functions in pre-frail older women. Patients and Methods: Sixty participants aged ≥ 65 years (81.5 ± 4.3 yrs) were divided equally into control group, diet group, aerobic exercise and diet group, and aerobic exercise with electromyostimulation and diet group. For 8 weeks, the participants received a set of protein-added meals twice daily on weekdays. The aerobic exercise groups performed 45 mins of stepping exercise at 50– 70% of the maximal heart rate for 3 days/week, and the aerobic exercise with electromyostimulation was applied on each limb in 8 weeks. Blood pressure, physical fitness, cardiovascular biomarkers, pulse wave velocity, and flow-mediated dilation were measured before and after the 8-week. Results: There were no group differences in age, height, weight, body mass index, free fat mass, and %body fat at baseline. The right grip strength significantly increased in the diet group, aerobic exercise and diet group, and aerobic exercise with electromyostimulation and diet group (p < 0.05). Short physical performance battery, 6-min walking distance, and flow-mediated dilation significantly increased in the aerobic exercise and diet group and aerobic exercise with electromyostimulation and diet group (p < 0.05). Blood pressure and pulse wave velocity did not differ between interventions. High-density lipoprotein-cholesterol levels significantly increased after 8 weeks in all intervention groups (p < 0.05). There were no significant differences in glucose, HbA1c, total cholesterol, low-density lipoprotein-cholesterol, triglyceride, insulin, Homeostatic Model Assessment for Insulin Resistance, nitric oxide, and C-reactive protein levels. Conclusion: These results show that multi-component interventions appear to improve physical fitness and vascular function in pre-frail older women. Thus, possible strategies to prevent early frailty including proper nutrition and exercise may be needed.

[Purpose] Continuous glucose monitoring (CGM) is on the rise as the prevalence of obesity and diabetes increases. This review aimed to explore the use of CGM and its potential novel applications in physical activity and nutrition management.[Methods] We searched PubMed, Web of Science, and Wiley Online Library databases using the keywords ‘continuous glucose monitor,’ ‘nutrition,’ ‘physical activity,’ and ‘numerical modeling.’[Results] Continuous blood glucose measurement is useful for individuals with obesity and diabetes. Long-term blood glucose data allow for personalized planning of nutritional composition, meal timing, and physical activity type and intensity, as well as help prevent hypoglycemia and hyperglycemia. Thus, understanding the limitations of CGM is important for its effective use.[Conclusion] CGM systems are being increasingly used to monitor and identify appropriate blood glucose controlling interventions. Blood glucose level is influenced by various factors such as nutrient composition, meal timing, physical activity, circadian rhythm, and cortisol levels. Numerical modeling can be used to analyze the complex relationship between stress, sleep, nutrition, and physical activity, which affect blood glucose levels. In future, blood glucose, sleep, and stress data will be integrated to predict appropriate lifestyle levels for blood glucose management. This integrated approach improves glucose control and overall wellbeing, potentially reducing societal costs.

The purpose of this study was to investigate the relationship of various aspects of daily physical activity, such as the number of steps, time spent in moderate to vigorous intensity physical activity (MVPA), and locomotive and non-locomotive MVPA measured by a triaxial accelerometer, with the functional fitness in healthy elderly men. The subjects of this study were 22 healthy elderly men aged over 65 years. The participants wore a triaxial accelerometer for two weeks to estimate their daily physical activities. The level of functional fitness was measured based on "National Fitness Award 100 in Korea" immediately after the measurement of two weeks of daily physical activities. The results showed that active healthy elderly men with more than 6,500 walking steps per day and more than 60 min per day spent in MVPA showed a significantly higher 2-min marching in place and index of cardiorespiratory endurance compared to less physically active participants. Particularly, locomotive MVPA was significantly associated with cardiorespiratory endurance levels (r = 0.50), whereas non-locomotive MVPA was not associated with other measurements of functional fitness. Increased MVPA time, especially the locomotive MVPA, can effectively suppress the decrease in cardiorespiratory endurance level in elderly men. However, no association was observed between non-locomotive MVPA, such as household activities, and functional fitness in healthy elderly men.