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Background: The purpose was to develop new maximal oxygen uptake (VO2max) prediction models using a perceptually regulated 3-minute walk test., Methods: VO2max was measured with a maximal incremental cycle test in 283 Japanese adults. A 3-minute walk test was conducted at a self-regulated intensity corresponding to ratings of perceived exertion (RPE) 13., Results: A 3-minute walk distance (3MWD) was significantly related to VO2max (r = .60, P < .001). Three prediction models were developed by multiple regression to estimate VO2max using data on gender, age, 3MWD, and either BMI [BMI model, multiple correlation coefficients (R) = .78, standard error of estimate (SEE) = 5.26 ml·kg-1·min-1], waist circumference (WC model, R = .80, SEE = 5.04 ml·kg-1·min-1), or body fat percentage (%Fat model, R = .84, SEE = 4.57 ml·kg-1·min-1), suggesting that the %Fat model is the best model [VO2max = 37.501 + 0.463 × Gender (0 = women, 1 = men) - 0.195 × Age - 0.589 × %Fat + 0.053 × 3MWD]. Cross-validation by using the predicted residual sum of squares (PRESS) procedures demonstrated a high level of cross-validity of all prediction models., Conclusions: The new VO2max prediction models are reasonably applicable to estimating VO2max in Japanese adults and represent a quick, low-risk, and convenient means for estimating VO2max in the field.

Context: Vaspin is an adipokine with insulin-sensitizing effects identified from visceral adipose tissues of genetically obese rats., Objective: We investigated genetic and nongenetic factors that define serum concentrations of vaspin., Design, Setting and Participants: Vaspin levels were measured with RIA in Japanese subjects with normal fasting plasma glucose (NFG; n = 259) and type 2 diabetes patients (T2D; n = 275). Single nucleotide polymorphisms (SNP) at SERPINA12 (vaspin) gene locus were discovered, and five SNP were genotyped in the subjects with varied body mass index (n = 1138)., Results: The level of serum vaspin in 93% of the samples was found to vary from 0.2 to nearly 2 ng/ml in NFG subjects (n = 259) and from 0.2 to nearly 3 ng/ml in T2D patients (n = 275) (Vaspin(Low) group), whereas a significant subpopulation (7%) in both groups displayed much higher levels of 10-40 ng/ml (Vaspin(High) group). In the Vaspin(Low) group, serum vaspin levels in T2D were significantly higher than healthy subjects (0.99 ± 0.04 vs. 0.86 ± 0.02 ng/ml; P < 0.01). Both in T2D and genotyped Japanese population, serum vaspin levels closely correlated with homeostasis model of assessment for insulin resistance rather than anthropometric parameters. By genotyping, rs77060950 tightly linked to serum vaspin levels, i.e. CC (0.6 ± 0.4 ng/ml), CA (18.4 ± 9.6 ng/ml), and AA (30.5 ± 5.1 ng/ml) (P < 2 × 10(-16)). Putative GATA-2 and GATA-3 binding consensus site was found at rs77060950., Conclusions: Serum vaspin levels were related to insulin resistance, and higher levels of serum vaspin in 7% of the Japanese population are closely linked to minor allele sequence (A) of rs77060950.

The link between changes in a subject's metabolic syndrome components and his estimated glomerular filtration rate (eGFR) was evaluated in healthy Japanese men. We used data from 120 Japanese men (45.5 ± 8.4 years) with a 1-year follow up. eGFR was defined by a new equation developed for Japan. There were no significant differences in eGFR between men with and without metabolic syndrome components at baseline. Subjects were given advice for dietary and lifestyle improvement. At the 1-year follow up, almost all metabolic syndrome components were significantly improved. However, eGFR was significantly decreased. The changes in eGFR were weakly correlated with abdominal circumference (r＝-0.232, p＝0.0106). A decrease in abdominal circumference may be associated with improving eGFR in Japanese men.

Using the homeostasis model assessment (HOMA) index, we investigated the link between insulin resistance and lifestyle in Japanese female university students. We used data for 57 Japanese female university students (21.0±0.8 years) who were enrolled in a cross-sectional investigation study. We performed full blood examinations, and anthropometric parameters, nutrient oral intake and daily step counts were measured. The mean HOMA index for the subjects was 1.3±0.6, and 12 subjects were over the level of 1.6, which is considered to indicate insulin resistance in Japan. The HOMA index was positively correlated with abdominal circumference (r＝0.542, p＜0.0001), triglycerides, low density lipoprotein (LDL) cholesterol and systolic blood pressure. In addition, the HOMA index was negatively correlated with n-3 fatty acid and positively correlated with the n-6/n-3 fatty acid ratio (r＝0.304, p＝0.0216). Daily step count was negatively correlated with the HOMA index, but not at a significant level (r＝－0.237, p＝0.0809). Higher HOMA index in some Japanese female university students was noted, and that was associated with lifestyle, especially n-6/n-3 fatty acid ratio of nutrient oral intake.

The link between changes in estimated glomerular filtration rate (eGFR) and cigarette smoking was evaluated in Japanese male workers with a 5-year follow-up. We examined the data of 456 Japanese male workers, aged 22-70 years, who were taking no medications, and from this group, 286 men (43.5±8.2 years) were followed for 5-years. Habits of cigarette smoking were obtained during interviews by well-trained staff. The influence of cigarette smoking on eGFR was evaluated. In the first analysis, there was no significant difference in eGFR between subjects with and without cigarette smoking. In the second analysis, eGFR was significantly reduced after 5 years in all subjects. Changes in eGFR in subjects with cigarette smoking (-1.90±12.31 ml/min/1.73 m²) were significantly smaller than those in subjects without cigarette smoking (-4.97±12.05 ml/min/1.73 m²). At follow-up, we found that eGFR was weakly and negatively correlated with the number of cigarettes smoked (/day). The present study indicated that cigarette smoking may be an important modifiable factor for eGFR in Japanese male workers who are not taking any medications.

The link between changes in a subject's metabolic syndrome components and her estimated glomerular filtration rate (eGFR) was evaluated in healthy Japanese women. We used data for 53 Japanese women (46.0±10.9 years) with a 1-year follow up. eGFR was defined by a new equation developed for Japan. There were no significant relationships between eGFR and clinical parameters at baseline. Subjects were given advice for dietary and lifestyle improvement. At the 1-year follow up, eGFR was significantly increased. In addition, changes in eGFR were weakly correlated with systolic blood pressure(r=-0.306, p=0.0260). A decrease in systolic blood pressure may be associated with improving eGFR in Japanese women.

We investigated the link between renal function as evaluated by estimated glomerular filtration rate (eGFR) and metabolic syndrome in Japanese. A total of 11,711 Japanese subjects, aged 20-79 years, were recruited in a cross-sectional clinical investigation. From this group, we further investigated the data on 1,576 subjects. eGFR was calculated using serum creatinine (Cr), age and sex. The diagnosis of metabolic syndrome was based on the Japanese criteria. In the first analysis, 288 men (7.8%) and 498 women (6.2%) were diagnosed with reduced eGFR (<60ml/min). eGFR was not correlated with anthropometric, body composition parameters in either sex. In the second analysis, in subjects without medications, 132 men (20.8%) and 15 women (1.6%) were diagnosed with metabolic syndrome. eGFR was lower in men with abdominal obesity and in women with hypertension was than in those without. Among Japanese not taking medications, lower eGFR may be a characteristic of men with abdominal obesity and of women with hypertension.

The aim of this study was to explore muscle strength and its relation to exercise habits in Japanese. We used data from 3,018 men and 6,881 women aged 20-69 years and not using medications in a cross-sectional study. Exercise habits and muscle strength, i.e. grip strength and leg strength, were measured. Age-related changes in muscle strength were noted. Exercise habits were found in 984 men (32.6%) and 1,664 women (24.2%). For subjects of both sexes over 50 years, grip strength was significantly decreased with age. However, the ratio of leg strength to body weight significantly decreased with age as early as 30 years in men and 40 years in women. Grip strength, leg strength and the ratio of leg strength to body weight in subjects with exercise habits were significantly higher than those without exercise habits after adjusting for age in both sexes. This standard mean value may provide a useful database for evaluating muscle strength in Japanese adult subjects.

The present study carried out a measurement of body composition and a nutrition survey, targeting 28 male wheelchair athletes and comparing them with 25 male physically able healthy athletes as the controls. The DXA method was used to measure bone mineral density (BMD), percentage of body fat (% body fat), and lean body mass (LBM). Possible factors affecting the BMD of the wheelchair athletes with spinal injuries were analyzed including age, body part, type of sport, area of injury, length of injury, and the length of time it took before restarting sports activity after injury. BMD in the arms, body trunk, legs, and entire body was measured. There were no significant differences in the BMD of the wheelchair athletes by age group (from 20 to 29, from 30 to 39, and 40 years and older), by sports (basketball, track and field, and tennis), and by area of injury (high and low paraplegia). BMD in the legs (r = -0.549, P < 0.01), body trunk (r = -0.414, P < 0.05), and entire body (r = -0.452, P < 0.05) of the wheelchair athletes was negatively correlated with the period since injury; however, no such a relationship was observed in the arms. In addition, the multiple regression analysis for BMD of each body region showed that the earlier the wheelchair athletes restarted sports after injury, the higher values the BMD of legs (r = -0.467, P < 0.05), body trunk (r = -0.469, P < 0.05), and entire body (r = -0.488, P < 0.05), independent of age and sports. The leg BMD of the wheelchair athletes was lower than that of the physically able athletes, with a BMD 76.5% of the controls. The present study suggests that restarting sports activity in a timely manner after treatment and rehabilitation for the injury is useful in preventing loss of BMD in wheelchair athletes and ultimately improving their quality of life.

We evaluated the linkage between oxygen uptake at the ventilatory threshold (VT) and muscle strength in subjects with and without metabolic syndrome. We used data of 226 Japanese men with metabolic syndrome and 265 Japanese men without the syndrome. Metabolic syndrome has recently been defined by a new criterion in Japan. Oxygen uptake at VT and muscle strength, i.e. grip strength and leg strength were measured. Oxygen uptake at VT and muscle strength/body weight were found to be significantly lower in subjects with metabolic syndrome than in those without the syndrome. However, the differences did not reach significant levels after adjusting for leg strength/body weight or oxygen uptake at VT. A combination of aerobic exercise and resistance training might be considered for preventing and improving metabolic syndrome.

We re-evaluated the criteria for waist circumference to predict the accumulation of the components of metabolic syndrome. We used data for 3,185 Japanese, aged 20-79 years. Metabolic syndrome has recently been redefined by a new criterion in Japan, in which waist circumference cutoff points, i.e. 85 cm for men and 90 cm for women, are employed. Among the 3,185 Japanese considered in the present study, 335 men (26.8%) and 69 women (3.6%) were diagnosed as having metabolic syndrome. A cutoff point as a predictor for 2 or more components of metabolic syndrome was evaluated by sensitivity/specificity and a receiver operating characteristic (ROC) curve. The optimal point was estimated as being approximately 85 cm of waist circumference in men and 75 cm in women. We therefore recommend a cutoff value, 75 cm of waist circumference, for the criterion of metabolic syndrome in women.

We compared muscle strength between Japanese men with and without metabolic syndrome. We used data for 323 Japanese men with metabolic syndrome and 893 Japanese men without the syndrome. Metabolic syndrome was defined by a new criterion in Japan, and the parameters for muscle strength, i.e. grip strength, leg strength were measured. Leg strength was found to be significantly higher in subjects with metabolic syndrome than in those without, while muscle strength per body weight was significantly lower in subjects with the syndrome. Lower muscle strength per body weight may be one of the characteristic features in subjects with metabolic syndrome.

We investigated the link between changes in body composition and the blood pressure (BP) response to exercise in overweight Japanese by a retrospective clinical study carried out over a 3-year period. We analyzed data for 38 overweight Japanese aged 22-69 years (47.8 +- 11.4) at baseline. Among the participants, 32 overweight subjects (body mass index : BMI, 29.0 +- 3.0 kg/m2) were further analyzed with a 3-year follow up. BP at rest, the BP response to an exercise test, the aerobic exercise-level determined ventilatory threshold (VT), and body composition were evaluated at an interval of 1 year. During the study period, there were 6 drop outs, who started to receive anti-hypertensive drugs because of the development of hypertension. Based on analysis of follow up data, parameters of body composition were significantly reduced over the 3 years. Systolic BP (SBP) at rest and at VT was also reduced. In addition, delta SBP (Delta: delta represents positive change in parameters) at VT was positively correlated with Delta parameters of body composition over the 3 years. In overweight subjects with increased body weight, there was a significant time (pre vs year 3) effect and interactions by 2 factor-factorial ANOVA. The present study indicates that changes in body composition are closely linked to the SBP response to an exercise test.

We compared the levels of hepatic enzymes in 220 Japanese men with metabolic syndrome with those in age and sex-matched subjects without the syndrome. Metabolic syndrome was defi ned by the new criteria published in Japan, and hepatic enzymes, i.e., aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma-glutamyl transpeptidase (gammaGTP), were measured. AST, ALT and gammaGTP in subjects with metabolic syndrome were significantly higher than those in subjects without the syndrome, and metabolic syndrome was closely associated with hepatic enzymes in this cohort of Japanese men.

Background: Prescription of aerobic exercise for obese subjects with mild hypertension in clinical practice remains to be investigated., Methods: Forty-one Japanese obese males with hypertension were enrolled and compared with 41 age-and sex-matched obese subjects without hypertension and control subjects. In addition, 25 obese subjects with or without hypertension participated in a one-year follow up study. They were instructed to keep their low exercise intensity and record their daily walking. Before and after exercise prescription, body composition, blood pressure and aerobic exercise level were evaluated. Ventilatory threshold (VT) was determined breath by breath during exercise test using a ramp protocol and rates of oxygen consumption (VO2), work rate (WR), heart rate (HR), deltaHR, %HR max, %HR reserve and rate of perceived exertion (RPE) were measured at VT., Results: At VT, obese subjects with hypertension had significantly lower VO2 (13.5 +/- 2.1 mL/kg/min) and WR (75.1 +/- 16.5W) than control subjects (VO2, 18.1 +/- 5.7; WR, 92.0 +/- 32.4). %HR reserve was also significantly lower compared with control subjects, while %HR max, was not different. RPE was also similar among the 3 groups. By prescribed low-grade exercise during one-year follow-up study, not only body composition but also blood pressure at rest was improved in obese subjects with and without hypertension., Conclusions: Our results indicated reduced exercise capacity in Japanese obese males. Exercise intensity of 60%HR max, 30%HR reserve and RPE 12 is recommended in obese subjects with hypertension as well as obese subjects without hypertension.

Purpose: We developed a one-year exercise program based on evaluation of life style and physical fitness and investigated its efficacy., Subjects and Methods: Sixty one Japanese males (30 < or = age < 59, body mass index: BMI > or = 26.4 kg/m2) were enrolled in the stady. The exercise program consisted of four sections: (1) Preparation for preventing injury; (2) Increase of daily activity; (3) Enjoying exercise; (4) Preparation and practice of individual-based on a exercise program. The subjects visited Okayama Southern Institute of Health and were being monitored weekly for one-year. They were instructed to check daily steps every day and increase daily walking to at least 1000 steps more than the daily walk at baseline. Before and after one-year follow up study, we evaluated life style and physical fitness in terms of body composition, aerobic exercise level, muscle strength and flexibility., Results: The continuation rate for the program was 66%. Body weight (pre 81.5 +/- 7.4 kg vs post 78.6 +/- 7.3 kg), body fat percentage (pre 30.3 +/- 4.1% vs post 28.4 +/- 5.0%) and waist hip ratio (pre 0.95 +/- 0.04 vs post 0.92 +/- 0.04) were significantly reduced. Aerobic exercise level and muscle strength were increased. Regarding volition for exercise, execution, continuation and steps per day were also improved., Conclusion: Regular exercise at an institution (once a week) and change in daily life style may play critical role in reducing body weight. This new program proved quite useful for Japanese obese males.

Objectives: To explore the potential use of ultrasound measurement (SoundScan 2000 Compact, Myriad Ultrasound Systems Ltd., Rehovot, Israel), and to assess both quantitative and qualitative properties of bone., Methods: The speed of sound waves (SOS; m/s) propagating along the cortical bone was determined at the tibial shaft. The performance, reliability, validity, and clinical application of this system were evaluated in Japanese subjects., Results: In phantom experiments, validity of this system was 0.04 (%), coefficient variation (CV: %) in same-day tests was 0.12, in five-separate-day tests was 0.13, and in independent operators was 0.11, respectively. In experiments with Japanese subjects, CV in same-day tests was 0.38, in five-separate-day tests was 0.99, and in independent operators was 0.90, respectively. In addition, cortical bone status of 1176 Japanese subjects (372 males, 804 females) was clinically evaluated by SoundScan 2000 Compact. SOS was negatively correlated with body fat percentage (%), body fat (kg) and waist hip ratio in females and subjects with higher weight bearing index (leg strength/body weight; WBI) have higher SOS in females under the age of forty., Conclusions: These findings indicate that the SoundScan 2000 Compact is a highly reliable and valid method for determining cortical bone status and body composition and WBI are closely related to cortical bone status in Japanese females.