The purpose of this study was to develop a simple and easy predictive model of leg, spine and whole body bone mineral density (BMD) from anthropometric, physical fitness, body composition and quantitative ultrasound (QUS) variables. Participants were 138 Japanese overweight and obese men (50.9 ± 9.6 yr, body mass index [BMI] 29.1 ± 2.6 kg/m²). We measured anthropometric variables (height, weight, BMI, chest, waist, hip, upper arm, thigh circumferences), physical fitness (grip strength, side steps, vertical jump, forced vital capacity), body composition (fat-free mass) and QUS. BMD was measured by dual energy X-ray absorptiometry. Multiple linear regression analyses showed that all predictive models for BMD were significant. As a result, the predictive model for leg BMD showed the highest model fitting. The Bland & Altman approaches demonstrated the (positive or negative) systematic error even though most plots were placed within ideal range. Predictive model from physical fitness, body composition and QUS would be useful for estimating whole body and regional BMD. Because these predictive models are likely to have some systemic errors, further research is needed to improve the predictive accuracy.

It has been reported that visceral fat (VF) is an independent predictor of the incidence for coronary heart disease, and is associated with its risk factors. The independent effects of exercise or dietary modification on VF remain to be fully elucidated, especially in obese middle-aged men. The purpose of this study was to investigate effects of exercise on VF compared to dietary modification. Thirty-five obese middle-aged men participated in this study. They consisted of exercise group (n=22, 51.4±11.6 yr, Group E) and diet group (n=13, 48.8±12.2 yr, Group D). Participants in Group E followed 90-min exercise sessions on a regular basis 3 days per week for 12 weeks. Participants in Group D attended weekly classes aimed at maintaining well-balanced 1,680 kcal/d diet for 12 weeks. Body weight decreased significantly in both groups (Group E : −2.9 kg, Group D : −5.4 kg). Visceral fat area (VFA) determined by computed tomography also decreased significantly (Group E : −32.0 cm², Group D : −39.4 cm²). An analysis of covariance adjusted by weight change revealed no significant group difference in VFA change. These results suggest that exercise-induced negative energy balance does not result in greater decrease in VFA as compared with dietary modification alone.

Purpose：The purpose of this study was to investigate the effects of change in daily physical activity during an exercise intervention on health status and physical fitness.Methods：Participants were 22 obese middle-aged men (BMI : 29.1±2.8 kg/m², 54.1±11.4 yr). They performed 90-min exercise sessions on a regular basis 3 days per week for 3 months. Physical activity (total energy expenditure, TEE ; activity energy expenditure, AEE ; and step counts) was measured using an accelerometer. Daily physical activity was defined as that which was performed outside of the exercise class. A 3-day food record was used to estimate energy intake. Results：Body weight decreased (-3.0±2.5 kg, P＜0.05). Vital age (VA), an index of comprehensive health status, and physical fitness age (PFA), an index of comprehensive physical fitness, significantly improved (VA : -8.7±5.5 yr, PFA : -8.5±5.1 yr, P＜0.05). Energy intake remained unchanged during the intervention (＋63.7±546.1 kcal/d). Daily physical activity increased (TEE : ＋83.0±130.1 kcal/d, AEE : ＋76.9±103.3 kcal/d, step counts : ＋1789±2819 steps/d, P＜0.05). Change in daily physical activity was correlated with change in VA (AEE : r＝-0.52, step counts : r＝-0.46, P＜0.05), while change in daily physical activity did not correlate with change in PFA. Conclusion：These results suggest that changes in daily physical activity during an exercise intervention are associated with improved health status.

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.

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.

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.