[Purpose] The purpose of this study was to evaluate the effects of a 12-week non-contact exercise intervention on body composition and health-related physical fitness in adults.[Methods] One hundred adults were initially enrolled; however, ninety-seven participants (men: n = 41, women: n = 56) completed the study. The non-contact exercise was performed for 12 weeks using a smart tracker (Charge 4, Fitbit, USA) and mobile phone applications. The non-contact exercise program included resistance, aerobic, and flexibility exercises.[Results] The results showed that percent body fat (<i>F</i>=4.993, <i>p</i>=.016, η_p²=.049), fat-free mass (<i>F</i>=4.690, <i>p</i>=.024, η_p²=.047), and skeletal muscle mass (<i>F</i>=5.623, <i>p</i>=.004, η_p²=.055) significantly changed during the intervention period. Further, significant increases were seen in hand grip strength (<i>F</i>=12.167, <i>p</i><.001, η_p²=.112), sit-and-reach (<i>F</i>=20.497, <i>p</i><.001, η_p²=.176), sit-ups (<i>F</i>=42.107, <i>p</i><.001, η_p²=.305), and VO_2max (<i>F</i>=4.311, <i>p</i>=.037, η_p²=.043).[Conclusion] Our findings suggest that 12 weeks of non-contact exercise improves body composition and health-related physical fitness. Wearable technologies encourage individuals to modify their lifestyles by increasing physical activity and achieving the goal of maintaining health conditions among adults.

Purpose The present study verified the effect of an m-health exercise intervention using a 12-week exercise program on body composition, vascular function, and the ANS. Patients and Methods Thirty obese adult women participants were randomized (n = 15 each) into the experimental (EXP) group, those who performed mobile-health (m-health) exercises using a wearable device (Charge 4, Fitbit, USA) and AI-fit web page, or the control (CON) group, those who continued their daily activities as before. Muscle function, cardiorespiratory endurance, and flexibility were assessed during the exercise program using the AI-fit web page and wearable device. The EXP group participated in exercise interventions using the m-health system for 12 weeks, while the CON group was encouraged to maintain their normal daily routines. Body composition, vascular function, and autonomic nervous system (ANS) were evaluated before and after the intervention. Results Significant decreases were noted in fat mass (Post - Pre: −1.47 kg; p < 0.001) and percent body fat (Post - Pre: −2.11%; p < 0.05). Flow-mediated dilatation (Post - Pre: 2.63%; p < 0.001) was significantly increased, and brachial-ankle pulse wave velocity (Post - Pre: −91.49 cm·sec −1 ; p < 0.01) was significantly decreased. RMSSD (Post - Pre: 10.43 ms; p < 0.01), NN50 (Post-Pre: 24.04; p < 0.05), pNN50 (Post - Pre: 7.70%; p < 0.05) and HF (Post-Pre: 179.60 ms 2 ; p < 0.05) increased significantly. Conclusion In conclusion, m-health exercise interventions using AI fit and wearable devices are effective in preventing obesity and improving vascular function, and ANS.

This study aimed to investigate the effects of acute moderate hypoxia (HYP), compared with those of normoxia (NORM), during endurance exercise with the same HR level on metabolic function, skeletal muscle oxygenation, and cardiac function. Twelve healthy men (aged 25.1 ± 2.3 years) completed 30 min of endurance exercise using a cycle ergometer with the same HR level (136.5 ± 1.5 bpm) corresponding to 70% maximal heart rate (HRmax) under NORM (760 mmHg) and HYP (526 mmHg, simulated 3000 m altitude) after a 30 min exposure in the respective environments on different days, in random order. Exercise load, rating of perceived exertion (RPE), metabolic function (saturation of percutaneous oxygen; SpO2, minute ventilation; oxygen uptake; VO2, carbon dioxide excretion; respiratory exchange ratio; RER, and oxygen pulse), skeletal muscle oxygen profiles (oxyhemoglobin, oxhb, deoxyhemoglobin, dxhb, total hemoglobin, and tissue oxygenation index; StO2), and cardiac function (heart rate, stroke volume, cardiac output, end-diastolic volume, end-systolic volume, and ejection fraction) were measured during endurance exercise. HYP showed a lower exercise load with the same RPE during exercise than did NORM. In addition, HYP showed a lower SpO2, VO2, oxygen pulse, oxhb, and StO2, and a higher RER and dxhb during exercise than NORM. We found that HYP showed lower exercise load and VO2 at the same RPE than NORM and also confirmed a higher anaerobic metabolism and oxygen inflow into skeletal muscle tissue due to the limitation of oxygen delivery capacity.

[Purpose] The purpose of the study was to investigate the effects of 4 weeks of lactate intake immediately after endurance exercise on maximal oxygen uptake (VO_2max) in exercise performance.[Methods] Seven-week-old mice from the Institute of Cancer Research (ICR) were randomly divided into four groups: vehicle intake (SE/CON), lactate intake (SE/LAC), endurance exercise with vehicle intake (EX/ CON), and lactate intake with endurance exercise (EX/ LAC). Mice were subjected to 60-70% VO_2max endurance exercise with or without oral lactate intake 5 days/ week for 4 weeks. VO_2max measurements (VO_2max, time to exhaustion (TTE), respiratory exchange rate, fat oxidation, and carbohydrate oxidation) were recorded at the end of the study period. After 48 h of VO_2max measurement, the mice were sacrificed, and three different abdominal fat samples (epididymal, perirenal, and mesenteric) were collected.[Results] Body weight and abdominal fat mass did not differ between the groups. When measuring VO_2max, endurance exercise raised VO_2max, and lactate intake after endurance exercise increased TTE. The change in energy substrate utilization during VO_2max measurement demonstrated that although the respiratory exchange rate and fat oxidation were enhanced by lactate intake, there were no synergistic effects of lactate intake and endurance exercise.[Conclusion] Lactate intake immediately after endurance exercises can improve exercise performance, indicating the benefit of long-term exogenous lactate intake as an exercise supplement.

This study investigated the acute effects of natural antioxidants, derived from yeast fermentation containing glutathione and dietary vitamin C supplementation, on metabolic function, skeletal muscle oxygenation, cardiac function, and antioxidant function during submaximal exercise in middle-aged triathlon athletes. Twelve participants (aged 49.42 ± 5.9 years) completed 90 min submaximal cycling trials corresponding to 70% maximal oxygen uptake with either vitamin C and glutathione (VitC+Glu), vitamin C (VitC), glutathione (Glu) supplementation, or placebo. Metabolic function (minute ventilation, oxygen uptake, carbon dioxide output [VCO2], respiratory exchange ratio [RER], oxygen pulse [O2pulse], carbohydrate oxidation, fat oxidation, and energy expenditure), skeletal muscle oxygenation (oxidized hemoglobin and myoglobin in skeletal muscle tissue, total hemoglobin and myoglobin in skeletal muscle tissue [tHb]), cardiac function (heart rate [HR], stroke volume [SV], cardiac output, end-diastolic volume, end-systolic volume, and ejection fraction), and antioxidant function parameters (blood lactate, superoxide dismutase, catalase, glutathione peroxidases, glutathione [GSH], diacron reactive oxygen metabolite [dROM], and biological antioxidant potential [BAP]) were measured during submaximal exercise and recovery. VCO2, RER, HR, blood lactate after exercise, and dROM were significantly lower, and O2pulse, tHb, and BAP were significantly higher for VitC+Glu than for the other trials (p < 0.05). In conclusion, combined vitamin C and glutathione supplementation was more effective in improving metabolic function, skeletal oxygenation, cardiac function, and antioxidant function during prolonged submaximal exercise in middle-aged triathletes.