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Circadian rhythms have been shown to regulate several physiological functions including body temperature, sleep/wake cycle, physical activity, and cognition. These functions are controlled by circadian clock genes, and the circadian clock system in the body is classified into two clocks which are the central clock in the suprachiasmatic nucleus (SCN) of the hypothalamus and peripheral clocks in peripheral tissues such as the liver and skeletal muscle. Therefore, many researchers are conducting basic and applied research on the relationship between circadian rhythm in peripheral tissues and physiological functions including sports performance and effects of acute exercise and exercise training. On the other hand, it has been shown that abnormal circadian rhythms and disturbance of circadian rhythms can lead to the development of several diseases such as diabetes, cancer, sarcopenia, depression, and dementia. Thus, it is also important to regulate individual circadian rhythm by considering for timing of exercise and daily physical activity. Exercise and physical activity are found to have an influence on circadian rhythms regulation (Chrono-exercise) and accumulate evidences between timing of exercise and health outcomes. This review aims to introduce evidence for chrono-exercise and suggests the importance for considering the timing of exercise and physical activity.
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Objective：This study aimed to examine the effects of kilohertz-frequency alternating current (KFAC) on muscle performance and adverse event in patients with neuromuscular skeletal disorders.Methods：A literature search was conducted in PubMed, PEDro, CINAHL, and Cochrane CENTRAL until September 2017. The reviewer extracted data on subject characteristics, intervention, target muscle, and outcome measures in accordance with the Cochrane Handbook.Results：The literature search yielded 1295 studies, and 3 studies met the inclusion criteria (n＝32；mean age：45.3 years). KFAC stimulation combined with land-based exercise was likely more effective in increasing the quadriceps femoris muscle strength than exercise alone in patients after total knee arthroplasty (TKA). However, KFAC was not superior to low-frequency pulsed current in increasing pedaling work in patients with spinal cord injury. No severe adverse event relevant to KFAC was reported in all 3 studies. The quality of evidence was very low according to the GRADE approach.Conclusion：Additional KFAC may be more effective than exercise alone in improving the quadriceps femoris muscle strength in patients after TKA without any severe adverse event. Further studies to investigate the effects of KFAC are warranted to increase the confidence for the effects of KFAC treatment.
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Since distal femoral varus osteotomy (DFO)
Subject(s)
Humans , Asian People , Japan , Knee , Osteoarthritis , Osteotomy , Tibia , Weight-BearingABSTRACT
Several studies have reported that molecular hydrogen (H<sub>2</sub>) acts as a therapeutic medical gas owing to scavenging reactive oxygen species (ROS). However, little is known about effects of H<sub>2</sub> on exercise-induced oxidative stress. The purpose of this study was to investigate the effects of weekly hydrogen bathing on exercise-induced oxidative stress and delayed-onset muscle soreness (DOMS). Nine healthy and active young men participated in this study, and each subject performed hydrogen bathing trial and placebo bathing trial in a crossover design. The subjects performed downhill running (8 % decline) at 75 % peak oxygen uptake (VO<sub>2</sub>peak) for 30 min, and each subjects conducted hydrogen or placebo bathing for 20 min, respectively, 1-6 days after downhill running. Before and after exercise, we measured visual analogue scale (VAS) and collected blood samples (Pre- and 5 min, 60 min after the end of bathing, 1day, 2days, 3days, 7days after downhill running). Blood sample analyses include creatine kinase (CK), myoglobin (Mb), malondialdehyde (MDA), reactive oxygen metabolites (d-ROMs), biological antioxidant potential (BAP), myeloperoxidase (MPO), interleukin-6 (IL-6), interleukin-17a (IL-17a) and lactate concentrations. Weekly hydrogen bathing had no effects of exercise-induced oxidative stress and muscle damage. On the other hand, hydrogen bathing significantly reduced DOMS (VAS) 1 and 2days after downhill running (p=0.033). These findings suggest that hydrogen bath after downhill exercise can be effective for reduction of DOMS.
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Limited evidence was available to support the effect of self-selected activities performed under free-living conditions on postprandial lipaemia, particularly for older adults. Thus, the aim of the present study was to examine the chronic effect of increased physical activity of daily living on postprandial triacylglycerol (TAG) in postmenopausal women. Twenty-eight postmenopausal women, aged 71 ± 4 years (mean ± SD), were randomly divided into two groups: active (n=14) and control (n=14) groups. The participants in the active group were asked to increase their activities above their usual lifestyle levels for 4 weeks; freely deciding the duration and intensity of their chosen activities. The participants in the control group maintained their usual lifestyle for 4 weeks. All participants were asked to wear a uniaxial accelerometer for 4 consecutive weeks. At baseline and after 4 weeks, all participants rested and consumed a standardised breakfast and lunch after a 24-h period of physical activity avoidance. Blood samples were collected in the fasted state (0 h) and at 2, 4 and 6 h after breakfast. After 4 weeks, the participants in the active group increased their step counts by 600 steps/day (from 6979 ± 2057 to 7586 ± 2301 steps/day, p=0.047). There was no difference in the pattern of postprandial TAG response between groups (trial × time interaction, p=0.335). A previous study has suggested that only recent exercise (i.e., 12h before but not 24 h before) appears to facilitate the exercise-induced postprandial TAG lowering effects. Thus, in the present study, postprandial lipaemia was not reduced after performing self-selected activities under free-living in postmenopausal women.
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<b>Objective:</b> The overproduction of reactive oxygen species leads to oxidative stress, which is related to lifestyle-related disease and cancer. Although antioxidants are considered as one of the countermeasures to oxidative stress, it is necessary to develop the assessment methodology for the antioxidant capacity which is closer to the inner body conditions. In this study, we examined antioxidant actions of plant extracts by using newly-developed neutrophil activity measurement system.<br> <b>Method:</b> Lemon verbena, Green tea, Camellia japonica and Antiallerge<sup>®</sup> were used as plant extracts, and were diluted to medium in wide-range concentrations. Each solution was added on modified Mebiol Gel<sup>®</sup> (hydrogel), and the mixture of blood and luminol were set onto the hydrogel in each tube. The amount of reactive oxygen species were measured by luminol-dependent chemiluminescence, whereas the cell count in the hydrogel was quantified as migratory activity of neutrophils.<br> <b>Result:</b> Lemon verbena and Green tea significantly inhibited reactive oxygen species in a concentration-dependent manner, whereas Camellia japonica and Antiallerge<sup>®</sup> did not. The migratory activity of neutrophils was not affected by those plant extracts. Also, damaged cells were not detected.<br> <b>Conclusion:</b> It was suggested that Lemon verbena and Green tea scavenged reactive oxygen species without causing cell death of neutrophils. This new method for measuring neutrophil activities can be applied not only for assessing the status of inflammation and oxidative stress but also as the screening system for predicting the effectiveness of antioxidant and anti-inflammatory substances.<br>
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The purpose of this study was to examine effects of moderate-intensity endurance exercise on reactive oxygen species production and leukocyte activation markers in young and middle-aged persons. Blood samples were collected before and after the jogging of 10 km. Although cytokines recruiting and priming neutrophils and monocytes were released into the circulation and functional after the jogging of 10 km, reactive oxygen metabolites-derived compounds (d-ROMs) were not significantly increased. It was indicated that chemokines and leukocyte activation markers at rest were increased with aging, and that might be accompanied by the higher level of d-ROMs in the elderly.<br>