Pelvic floor dysfunction as a representative of pelvic frailty / 体力科学

Pelvic floor trauma developing into pelvic frailty is a significant concern in urogynecology or orthopedics. The majority of women who have experienced vaginal childbirth are affected, to a certain extent, by some form of pelvic floor damage, thereby eliciting substantial alterations of functional anatomy in the pelvic cavity which are manifested as urinary incontinence or pelvic organ prolapse (e.g., uterine prolapse). With the above in mind, medical researchers, continence experts, and continence exercise practitioners in the research areas of sports medicine and rehabilitation medicine believe that the coordinated activity of pelvic floor muscles, in association with the abdominal muscles, is a prerequisite for urinary and defecatory continence. Since the pelvic floor forms the base of the abdominal cavity, stronger pelvic floor muscles are crucial in maintaining such capabilities. Opposing action of the abdominal and pelvic floor muscles ensures that exercises for one may also strengthen the other. Appropriate abdominal maneuverability or logical exercise training of the abdominal muscles may thus be beneficial in maintaining not only strength but also coordination, flexibility, and endurance of pelvic floor muscles and abdominal muscles. Such exercises, collectively known as pelvic floor muscle training, may be effective for long-term pelvic cavity care and also in rehabilitating cases of pelvic floor dysfunction. Further research is needed, however, in determining whether pelvic floor muscle function can be truly enhanced or maintained by such exercises in cases of pelvic floor dysfunction and/or decreased urinary continence.

Effectiveness and protocols of pelvic floor muscle exercise for the treatment of urinary incontinence in older people / 体力科学

Urinary incontinence (UI) among older people is a common problem. Several treatments are available for older people with UI including surgery, drug therapies, and behavioral interventions. Recently, much attention has been placed on the behavioral treatments for UI, including pelvic floor muscle (PFM) exercise, weight loss exercise, and thermal therapy, as they have few risks, no side effects, and are effective. These therapies are often recommended as first line treatments for older people with UI. PFM exercise programs often incorporate alternations of fast contractions that are usually held for about two to three seconds interspersed with relaxation intervals of four to five seconds, and sustained contractions, where participants hold the contraction for about eight to ten seconds followed by a relaxation interval of ten to twelve seconds between the contractions. While exercise periods vary between 3 to 24 weeks, 8 to 12 weeks seems to be the most effective length for PFM exercise. The effectiveness of PFM exercise for the improvement of UI has been validated by many studies, with improvement rates ranging widely from 17 to 84%. Also, research has shown that UI is associated with obesity. Increases in body weight cause increases in abdominal wall weight, which in turn increases intra-abdominal pressure and intra-vesicular pressure. Therefore, abdominal fat reduction from exercise may decrease intra-abdominal pressure, perhaps causing improvements in urethral sphincter contraction and, hence, decreasing UI risk. Evidence reveals that PFM exercise and fitness training targeted at reducing modifiable risk factors are effective strategies for treating UI in older people, regardless of UI type.

Effects of high-molecular-weight polyphenol supplementation on physical fitness age in physically active middle-aged and older women: Randomized controlled trial / 体力科学

Mitochondria activation factor (MAF) which is high-molecular weight polyphenol contained in black tea and oolong tea can increase the mitochondrial membrane potential. MAF supplementation to mice facilitates endurance running performance after 9-week endurance training and muscle hypertrophy induced by synergist ablation. In this study, we examined the effect of oral MAF supplementation on overall physical fitness (expressed as physical fitness age) in physically active middle-aged and older women. This study is a randomized double-blind placebo-controlled trial implemented between January and May 2019 at three fitness facilities in Ibaraki, Japan. Seventy middle-aged women aged 55 to 69 years were randomly assigned into placebo (n = 35) and MAF groups (n = 35). The placebo participants took cornstarch-containing capsules, and the MAF participants took MAF-containing capsules twice a day for 80 days consecutively. During the intake period, all participants were instructed to follow 30-min circuit training program at least twice a week. Physical fitness age was computed with eight physical fitness items assessing upper-extremity muscle strength, locomotion, and postural change. The physical fitness age decreased by 1.48 years (95% confidence interval [CI]: -2.66, -0.30) in the placebo group and 3.01 years (95% CI: -4.16, -1.86) in the MAF group. The reduction was greater in the MAF group, but did not reach statistical significance (p = 0.06). The combination of 80-day of MAF intake and circuit exercise showed beneficial results. However, our results did not indicate clear effects on physical fitness age because of low statistical power. Further studies are necessary to reveal the effects of MAF supplementation.

Weight loss maintenance for 1 year after a 6-month diet and physical activity program in obese Japanese men / 体力科学

This study described 1-year changes in body weight and metabolic syndrome components in middle-aged obese Japanese men participating in a 6-month weight loss program. This study comprised two phases: 6-month weight loss program and 12-month weight maintenance. Data were collected at Tsukuba, between July 2009 and February 2011. Overweight or obese Japanese men aged 40-64 years without any cardiovascular disease history participated. The primary outcome was the 18-month weight change. Secondary outcomes were 18-month changes in metabolic syndrome components. Primary analyses included all participants who had provided baseline data, and all missing follow-up values were replaced with their baseline data. Of the 58 participants, 39 (67.2%) completed all measurement visits. Their body weight decreased significantly immediately after the 6-month weight loss program (-8.0 kg; 95% confidence interval [CI]: -10.2 kg, -5.8 kg). However, it increased significantly, by 3.7 kg (95% CI: 1.4 kg, 6.0 kg), at Month 18 (a year after the program ended). The 18-month weight loss was 4.3 kg (95% CI: 2.1 kg, 6.5 kg). Among the metabolic syndrome components, visceral fat area, systolic blood pressure, and high-density lipoprotein cholesterol levels improved significantly at Month 18. The other components did not improve over the 18 months. In this study, the obese, middle-aged Japanese men experienced modest weight regains after its substantial reduction. Unlike other ethnicities, factors associated with long-term weight loss maintenance remain understudied among Japanese adults. Therefore, accumulating evidence from Japanese studies with longer follow-up is necessary in the future.

Physical fitness level in Japanese breast cancer survivors / 体力科学

It has been reported that physical fitness of breast cancer patients is relatively lower due to the cancer treatment such as surgery, chemotherapy, or endocrine therapy. Previous studies have revealed that not only cardiorespiratory fitness but also muscle strength is lower among breast cancer patients than no disease women and these symptoms may aggravate the health-related quality of life. However, there is no study which has focused the physical fitness level in Japanese breast cancer survivors. The purpose of this study was to investigate the physical fitness level and the relationship between exercise habituation and physical fitness level in Japanese breast cancer survivors. Fifty breast cancer survivors participated in this study. Participants were assigned to either exercise habituation group (n=25) or non-exercise group (n=25). We evaluated exercise habituation using an original questionnaire and examined various physical fitness level. Body weight, body mass index, and percent body fat were significantly lower in the exercise habituation group than non-exercise group. T-score of cardiorespiratory fitness was significantly higher in the exercise habituation group than average Japanese women. These results suggested that exercise habituation is relative to body weight and cardiorespiratory fitness level in Japanese breast cancer survivors.

Need for peri-operative weight loss among obese colorectal cancer patients / 体力科学

Colorectal cancer patients account for the largest proportion of total cancer patients in Japan. With an increase in its surgical cases and relatively higher five-year survival rate, the number of cancer survivors is expected to be increasing. Therefore, primary prevention, surgical therapy and recurrence prevention for colorectal cancer are public health priorities in Japan. General and abdominal obesity (Not only abdominal but also general obesity) are risk factors for colorectal cancer. In addition, accumulated abdominal fat can extend time spent in surgery by hindering operative procedures and surgical field expansion. These factors raise the risk of postoperative complications such as bleeding and surgical site infection, which eventually leads to increased medical expenses. Physical activity is one of protective factors for colorectal cancer. Recent studies showed that exercise intervention in cancer survivors reduces the cancer recurrence risk. Furthermore, it has been suggested that exercise interventions are effective in reducing fatigue, improving immune function, and maintaining physical function. However, the effectiveness of preoperative exercise intervention aimed at reducing weight in colorectal cancer patients remains unknown. In this review article, we discuss necessity for peri-operative weight loss among obese colorectal cancer patients.

Association between the timing of habitual physical activity and sleep in older adults / 体力科学

<p>We examined the relationship between the timing of habitual physical activities and sleep quality in older adults. The subjects were Japanese community-dwelling older adults (n=49, average age 70.1±3.5 years; men: 36.7%). We measured habitual physical activity using a 3-axis accelerometer (HJA-350 IT, Omron) for a week. Timing of physical activity was classified into the following three periods: (1) morning: waking to 11:59, (2) afternoon: 12:00 to 17:59, and (3) night: 18:00 to bedtime. We also categorized the intensity of habitual physical activity during 2 sessions as either (1) low (1.6-2.9 METs) or (2) moderate-to-vigorous (≧3.0 METs) intensity. The subjective sleep parameters were assessed using the Pittsburgh Sleep Quality Index (PSQI). We used a forced-entry multiple regression analysis to investigate the relationships between subjective sleep parameters and the timing of physical activities. Forced-entry multiple regression analysis revealed that sleep latency and PSQI global score were positively correlated with low-intensity physical activity at night. However, there was no significant correlation with moderate-to-vigorous activity. These results suggest that low-intensity habitual physical activity at night would be one useful and modifiable factor to improve sleep quality in the elderly.</p>

Equations to estimate visceral adipose tissue volume by a single-slice method / 体力科学

<p>Although it is common to assess visceral adipose tissue (VAT) by CT and MRI with a single slice at the umbilicus or the fourth and fifth lumbar vertebrae (L4-L5), recent studies reported that this single-slice method for determining an individual’s VAT may be inaccurate. Therefore, VAT accumulation should be based on total volume and determined with multiple slices rather than by cross-sectional area. However, obtaining multiple slices is burdensome for both subjects and analysts and lacks versatility despite its accuracy. The purpose of this study was to develop a new equation model for predicting VAT volume while maintaining the measurement accuracy of the multiple-slice method. We analyzed data from 214 Japanese male adults (48.5±9.3 years) and developed multiple, stepwise, linear regressions with VAT volume as a dependent variable and age, BMI, waist circumference and VAT areas (the standard L4-L5 measurement site 0 cm, +5 cm, +10 cm) as independent variables. From these results, we determined the best prediction equation for VAT volume as follows: VAT volume = (30.4×BMI) + (17.9×VAT area at L4-L5+10 cm) – 501.5. The model explained 93.1% of VAT variance and the predicted VAT volume significantly correlated with the measured VAT volume (r=0.97). This study developed a new VAT assessment method with a high level of accuracy. The method is significantly less burdensome in measurement and analysis than the multiple-slice method. Researchers can use this equation when they require an accurate evaluation of VAT accumulation. However, they should bear in mind that this equation was derived from data acquired from middle-aged, overweight and obese male subjects.</p>

Is it possible to increase muscle mass and basal metabolic rate during weight loss? / 体力科学

<p>Most people who go to fitness clubs or sports gyms for weight control, and many co-medicals and physicians believe that an increase in muscle mass and/or basal metabolic rate (BMR) is possible through a combination of regular exercise and optimal protein intake during weight loss. This seems a myth, and the reasons are discussed in this article. First, muscle mass is quite difficult to quantify. The limitations of body composition measurement should be well understood. Second, increasing muscle mass during weight loss is difficult. This might be attained through strict implementation of a protein-rich, low-carbohydrate diet; high-intensity resistance training; and aerobic exercise for a long duration. However, such a strict regimen is not feasible for most people. Finally, a 1-kg increase in muscle mass corresponds to an increase of only 13 kcal of BMR per day. Thus, an increase in muscle mass of 1 kg is difficult to achieve, while the gained BMR is approximately equivalent to a decrease of 13.5 kcal of BMR according to a 3-kg decrease of adipose tissue. Weight loss, unless through an extremely sophisticated weight control program, contributes to a decrease in BMR. However, it is an accomplished fact that women with significantly less muscle mass and lower BMR live longer than men with more muscle mass and higher BMR, regardless of ethnicity. Maintaining activities of daily living and daily activity function might be more essential.</p>

Impact of Having Action Plan and Self Efficacy Score on Physical Activity Action Change after One Year / 日本プライマリ・ケア連合学会誌

<b>Introduction</b>: The present study was conducted to identify the influence of self-efficacy score and having an action plan on “stages of change” for exercise after one year.<br><b>Methods</b>: Physical functions and psychological factors at baseline and after one year in 105 elderly individuals who participated in a preventive care program. The subjects were classified into four groups by using the stages of change scale for physical activity.<br>The cause related to impact on physical activity and action stage change (stage) after one year later with having or not having action plan for preventive care program in elderly at home in community as well as sense of self efficacy was investigated.<br><b>Results</b>: Self-efficacy scored significantly higher in the usual activity group with continuity of stage activity both at baseline and one year later. The relative risk of having an action plan at baseline for exercise after one year was 2 . 90 (95% CI: 1.52-5.55). This value significantly influenced the maintenance of physical activity after one year.<br><b>Conclusion</b>: The results of this study suggest that showing an action plan was effective in maintenance of physical activity.

Effects of exercise for older married couples on exercise adherence and physical fitness / 体力科学

The purpose of this study was to examine the effects of an exercise intervention for older married couples on exercise adherence and physical fitness. Thirty-six older married couples and 61 older adults participated in the study as couple and non-couple groups (CG, NCG, respectively). Participants attended an exercise class once a week and performed a home-based exercise program consisting of walking and strength exercise over eight weeks. Exercise adherence was assessed by the rate of non-absentee, walking habits (≥ 2 times/week), and strength exercise habits (≥ 6 items*2 sets/week). Physical fitness was assessed by the Senior Fitness Tests. Logistic regression analyses were conducted to obtain the CG’s odds ratios (ORs) and 95% confidence interval (CI) for non-absentee, walking habits, and strength exercise habits (reference: NCG). Analyses of covariance were used to examine the statistical difference in the degree of change (⊿) for physical fitness between CG and NCG. CG had significantly higher ORs for non-absentee and walking habits compared with NCG but there was no significant difference in the rate of strength exercise habits between the two groups. In regards to ⊿ for physical fitness, significantly higher ⊿ for upper extremity strength was observed in CG than in NCG, while there were no significant differences in ⊿ for other physical fitness items between the two groups. These results suggest that an exercise intervention for older married couples would be more useful to maintain higher participation in exercise program and walking and improving upper extremity strength.

Liver, Muscle, and Insulin Resistance in Obese Subjects: Exercise Effects / 体力科学

Both westernization of diet and lifestyle habits and chronic inactivity have accelerated the obese population in Japan. Obesity is defined as being a condition in which the excessive energy is stored in the body as fat. Irrespective of organs and tissues, excessive fat accumulation impairs their structure and function, that is, ectopic adiposis. These days, the rapid increase in the number of adult people with abnormal liver function associated with obesity is largely attributed to an increase in the incidence of non-alcoholic fatty liver disease (NAFLD), a chronic liver disease accompanying fat accumulation. In Japan, about 30% of obese people suffer from NAFLD. About 10% of NAFLD progresses to non-alcoholic steatohepatitis (NASH). NASH is a progressive disease leading to liver cirrhosis. Any treatment with consensus other than diet restriction and exercise training is ineffective for the prevention of onset and progression of NAFLD. The important thing is a practice of suitable amounts of exercise, since it maintains muscle volume, increases the utilization of glucose, and attenuates insulin resistance, all of which may contribute to a decease in hepatic fat accumulation levels. It may be of great significance to practice exercise training for patients with chronic liver disease for improving the liver pathophysiology of NAFLD. In this review, first, the onset mechanism for NAFLD in obese subjects is summarized; second, beneficial effects of exercise on liver pathophysiology of NAFLD are reviewed based on the data from a weight reduction program consisting of dietary restriction plus aerobic exercise; and finally, medical support of obese patients with NAFLD in Tsukuba University Hospital are introduced.

Translating physical activity reference value for older adults to the number of steps per day / 体力科学

Although the physical activity reference value for older adults (10 METs*hour/week) has been promoted by Japan Ministry of Health, Welfare, and Labour since 2013, little is known about how many steps/day cut-off values that optimally identify meeting the reference value according to the differences of age, sex, medical history, and joint pain. The purpose of this study were 1) to determine the steps/day that optimally identify meeting the reference value, and 2) to identify the differences by the effects of age, sex, medical history, and joint pain on cut-off values. This study included 583 community-dwelling older Japanese adults (aged 73.2 ± 5.4 years; 153 men, 430 women). A uniaxial accelerometer survey was conducted to estimate the total physical activity volume and steps/day. Receiver operating characteristic (ROC) analyses were used to detect steps/day cut-off values for meeting the reference value among all participants and stratified by age, sex, medical history, and joint pain. The optimal cut-off value (AUC (area under the ROC curve), sensitivity, and specificity) for the reference value was 4376 steps/day (0.99, 95.2%, and 97.2%) in all participants. Differences among the cut-off values according to age, sex, medical history, and joint pain ranged from 39 to 169 steps/day. These results suggest that step counts has satisfactory validity to represent the reference value in older adults, and the effects of age, sex, medical history, and joint pain on cut-off values were considerably small. Therefore, this step-count level may be a useful indicator for modifying the daily-life activities of older adults.

Lifestyle intervention-induced increase in light physical activity may improve insulin resistance in overweight and obese men / 体力科学

Moderate to vigorous physical activity is associated with improving insulin resistance in overweight and obese adults. However, effect of light physical activity on insulin resistance remains to be fully elucidated. The purpose of this study was to investigate the effect of light physical activity on insulin resistance in overweight and obese men. Thirty-seven overweight and obese middle-aged men (28.9 ± 1.8 kg/m², 51.0 ± 8.8 years) participated in this study. They took part in the lifestyle intervention (calorie restricted diet and exercise) for 12 weeks. Anthropometric parameters, fasting glucose, HbA1c, fasting insulin, and HOMA-IR were assessed at baseline and post intervention. Physical activity was objectively measured using a triaxial accelerometer at baseline and during intervention. Light physical activity (+17.7 min/day) and moderate-vigorous physical activity (+33.2 min/day) increased significantly, while body weight (-12.4 kg), fasting glucose (-9.5 mg/ml), fasting insulin (-4.2 μU/ml), and HOMA-IR (-1.1) decreased significantly. The change in light physical activity from baseline to during intervention were inversely related to change in fasting insulin (r = 0.18, <i>P</i> = 0.02) and change in HOMA-IR (r = -0.16, <i>P</i> = 0.03), after adjustment for several confounders. These results suggest that an increase of light physical activity improves insulin resistance in overweight and obese men.

Habitual exercise and falls among community-dwelling older Japanese adults / 体力科学

The purpose of this study was to retrospectively examine the association of habitual exercise with “single fall (= 1)”, “multiple falls (≥ 2)”, and “injurious falls (≥ 1)” among community-dwelling older adults. A total of 1,683 community-dwelling older adults, aged 60-97 years (72.6 +/- 6.6 yr, 512 men and 1,171 women) were included in this study. Habitual exercises continued one year or longer (6.4 +/- 9.5 yr) were classified into twelve types. Exercise components (time, quantity, period of continuity, and number of exercises) were divided with median or tertiles. To assess the association between habitual exercises and fall status, multivariable logistic regression analyses with stepwise selection method, were applied. The multivariable logistic regression analyses showed that dance (odds ratio (OR): 0.30, 95% confidence interval (CI): 0.09-0.96) was negatively associated with “single fall”. Bicycling (OR: 3.72, 95% CI: 1.32-10.77) was positively associated with “multiple falls”, and the period of continuity (OR: 0.74, 95% CI: 0.60-0.91) was negatively associated with “multiple falls”. None of the exercise components were selected with regard to “injurious falls”. Results indicate that dance may be an effective type of exercise for fall prevention among community-dwelling older adults. However, caution about falling is warranted toward bicycling as an exercise. Moreover, a longer period of continuity (≥ 4 years) appears to be a positive factor of habitual exercise for fall prevention.

The effects of whole-body vibration training on knee function and physical performance of middle-aged and elderly woman with knee osteoarthritis and chronic knee pain / 体力科学

The purpose of this study was to elucidate the effects of whole-body vibration training (WBVT) on knee function and physical performance in middle-aged and older Japanese women who suffered from knee osteoarthritis (OA) and knee pain. Thirty-eight middle-aged and older Japanese women (aged 50-73 years) with knee OA and knee pain were divided into two groups: (1) a WBVT group (n = 29) engaging in WBVT 3 times a week for 8 weeks, and (2) a control group (C group, n = 9) performing exercises at home. The WBVT program consisted of a warm-up, strength training mainly of the quadriceps and their surrounding muscles and cool-down exercises. In the WBVT group, there were no dropouts, and there were significant improvements in the physical function (Cohen’s <i>d</i> = 0.28) and total score (Cohen’s <i>d</i> = 0.25) of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). There were also statistically significant improvements in all lower-extremity function tests (5-times sit-to-stand, timed up and go, standing time from a long sitting position, sit and reach, 4-way choice reaction time; Cohen’s <i>d</i> = 0.34-1.24). The item that changed significantly in the C group, however, was only the sit and reach (Cohen’s <i>d</i> = 0.52). In addition, all items in the Japanese Orthopaedic Association Score (JOA score) improved significantly (Cohen’s <i>d</i> = 0.63-0.67) in the WBVT group. In conclusion, the 8-week WBVT program can safely improve knee function and physical performance in middle-aged and older Japanese women who suffer from knee OA and knee pain.

The effects of dietary modification, aerobic exercise training, and combined dietary modification and aerobic exercise training on central and peripheral arterial stiffness in obese men / 体力科学

Obesity and increasing of arterial stiffness are known as independent risk factors for cardiovascular disease. Previously, we demonstrated that dietary modification or aerobic exercise training can decrease arterial stiffness in obese individuals. However, it has not been compared the effect of dietary modification and/or aerobic exercise training on arterial stiffness in obese men. We compared the effect of three patterns of lifestyle modification (i.e., dietary modification, aerobic exercise training or combined them) on arterial stiffness in obese men. Fifty-three obese men completed the 12-week lifestyle modification program, dietary modification (D), aerobic exercise training (E) or combined D and E (DE). Before and after the program, all participants were measured central, peripheral, and systemic arterial stiffness (measured by carotid-femoral pulse wave velocity [cfPWV], femoral-ankle PWV [faPWV] and brachial-ankle PWV [baPWV]). We demonstrated that the degree of decrease in BMI was the greatest after DE, and that was greater after D than E. The level of decrease in baPWV after DE was the greatest among three interventions. On the other hand, the level of decrease in baPWV in D group was similar to E group. These results suggested that systemic arterial stiffness may be decreased by different mechanisms between D and E groups. We demonstrated that dietary modification decreased central and systemic arterial stiffness, and aerobic exercise training decreased central, systemic, and peripheral arterial stiffness in obese individuals. We also showed an additional effect of decreasing systemic arterial stiffness by combining dietary modification and aerobic exercise training in obese individuals.

Is habitual sedentary behaviour time associated with lower extremity performance independent of moderate- to vigorous-intensity physical activity in older adults? −Cross-sectional analysis using uniaxial accelerometer– / 体力科学

Habitual moderate- to vigorous-intensity physical activity positively impacts lower extremely performance in older adults. However, little is known whether habitual sedentary behaviour time independently impacts lower extremity performance. The purpose of this cross-sectional study was to identify whether sedentary behaviour time is associated with lower extremity performance independent of moderate- to vigorous-intensity physical activity time in older adults. Eight-hundred-and-two community-dwelling older Japanese adults (72.5 ± 5.9 years) participated in this study. Sedentary behavioir time and moderate- to vigorous-intensity physical activity time were assessed using a uniaxial accelerometer. Lower extremity performance was assessed by repeated chair stand, single leg stance, and timed up and go tests. Jonckheere terpstra trend test and Spearman rank correlation coefficient were used to identify the single relation between sedentary behaviour time and lower extremity performance. A hierarchical multiple regression analysis was used to identify whether sedentary behaviour time is associated with lower extremity performance independent of moderate- to vigorous-intensity physical activity time. Results of single relation analysis showed there were negative associations between sedentary behaviour time and all lower extremity performance tests. Multivariable analysis indicated that sedentary behaviour time was not significantly associated with any lower extremity performances but moderate- to vigorous-intensity physical activity time was positively associated with all lower extremity performance tests. In conclusion, sedentary behaviour time would be less useful than moderate- to vigorous-intensity physical activity time as an indicator for modifying habitual behavior to maintain good lower extremity performance in community-dwelling older adults.

Cross-sectional association between body mass index and muscle strength, and mobility limitation in community-dwelling older women / 体力科学

This study aimed to examine the association between body mass index (BMI) and muscle strength, and mobility limitation (ML). A cross-sectional analysis was conducted on data from 570 community-dwelling older Japanese women aged 65-91 years [mean age, 73.9 ± 5.8 (SD) years]. Muscle strength was assessed by hand-grip strength (HGS). ML was assessed using self-reported difficulty level in walking 400 m and ascending 10 steps without resting. BMI and muscle strength were divided into tertiles (high: BMI ≧ 25.1 kg/m², HGS ≧ 22.5 kg; middle: BMI 22.4-25.0 kg/m², HGS 18.8-22.4 kg; low: BMI ≦ 22.3 kg/m², HGS ≦ 18.7 kg) respectively, and logistic regression analysis was used to determine the association between BMI and muscle strength with ML. 256 participants (44.9%) were identified as having ML. Adjusted odds ratios of BMI for ML were 1.64 (95% confidence interval (CI): 1.00-2.68) in the middle group and 1.89 (95% CI: 1.15-3.12) in the high group when compared to the low group. Adjusted odds ratios of muscle strength for ML were 1.25 (95% CI: 0.77-2.04) in the middle group and 1.85 (95% CI: 1.11-3.09) in the low group when compared to the high group. Compared to the low BMI plus high muscle strength group, adjusted odds ratio for ML was significantly higher in the high BMI plus low muscle strength group (2.65, 95% CI: 1.02-6.87) and the high BMI plus middle muscle strength group (3.09, 95% CI: 1.25-7.61). Our findings indicate that the combination of overweight plus muscle weakness is more predictive for having ML than overweight or muscle weakness alone.

Relationship between physical activity and sleep in community-dwelling older adults / 体力科学

This study examined relationships between physical activity and sleep relative to leisure-time, household, and occupational physical activity in community-dwelling, older adults. From 3,000 randomly chosen community-dwelling, adults, aged 65-85 years, we recruited 509 eligible subjects (mean age 73.2 ± 5.1 years). We assessed nocturnal sleep duration, sleep onset latency and subjective sleep quality over the previous month through a questionnaire. Physical Activity Scale for the Elderly was used to assess leisure-time, household, and occupational physical activity. Items pertaining to sleep were expressed as dichotomous variables (good/poor), and each physical activity score was divided into two categories based on activity level. To investigate the relationship between sleep (dependent variable) and physical activity (independent variable), we used a logistic regression analysis, controlling for age, gender, living arrangement, depressive symptoms, and cognitive function. Prolonged sleep latency was significantly related to no participation in low intensity exercise (OR 2.14; 95% CI 1.42-3.21) and muscle strength exercise (OR 1.99; 95% CI 1.06-3.74). Our data suggest that not participating in low intensity exercise or muscle strength exercise may be associated with difficulty initiating sleep in older adults.