A new approach to assessment of energy expenditure during physical training / 体力科学

While the session-RPE (rating of perceived exertion) method can quantify training volume in athletes, this method is not able to evaluate energy expenditure (EE) during a training session. We developed an RPE-based activity record for assessing EE during athletic training, and we compared its results to those obtained using the flex-heart rate (flex-HR) method. The EE of nine female collegiate endurance runners was assessed by the RPE-based activity record and flex-HR methods during eight days in the normal training season. Subjects were asked to record their RPE in the record at 5-minute intervals, and to wear a HR monitor during training. All subjects also participated in an incremental treadmill exercise test, which was used to determine their RPE-EE and HR-EE regression equations. Although the RPE-based activity record significantly overestimated EE (RPE-activity record, 572 kcal/session; flex-HR method, 499 kcal/session; <i>p</i> = 0.031), it had high validity relative to the flex-HR method (intra-class correlation coefficient, 0.891; 95% confidence interval, 0.845–0.923) and there were no systematic errors in EE estimation between the two methods. Therefore, the RPE-based activity record can be used to assess EE during training in female runners. However, RPE-based activity record might overestimate EE for athletes who have more intermittent activities during training than endurance runners, because RPE takes more time for returning to the resting level than HR when the intensity of activity declines. Further research is needed to verify the validity of the RPE-based activity record for assessing EE during other sporting activities or measurement conditions, and to identify the factors affecting the degree of estimation error associated with this method.

High basal metabolic rate/fat-free mass ratio in Japanese elite male athletes can be attributed to body composition / 体力科学

The aim of the present study was to evaluate the relation between basal metabolic rate (BMR) and body composition in 29 Japanese elite male athletes (age 25.6±3.7y, height 175.6±7.0cm, body weight 74.7±12.8kg, fat-free mass (FFM) 64.9±9.3kg). The subjects were classified into three groups according to their FFM. There was a significant difference in BMR/FFM between S-group (less than 0.5SD of average FFM) and L-group (more than 0.5SD). The parcentage of RM to body weight in S-group was significantly higher than in L-group. In conclusion, high basal metabolic rate/fat-free mass ratio in Japanese elite male athletes can be attributed to body composition.

Relationship Between Subjective Fatigue by Exercise and Stress Hormone and Cytokine Variables / 日本補完代替医療学会誌

We analyzed the relation between subjective fatigue by hard exercise and stress hormone and cytokine data. The subjects are eight healthy men who had exercise experience. In this experiment, hard exercise was carried out in the first place. After two-hour rest, a performance test was carried out. The blood test was conducted 4 times (before exercise, after exercise, rest, and a performance test). Subjective fatigue was indicated using visual analogue scale (VAS). After the hard exercise and performance test, VAS increased and showed the significant difference. Lactic acid, adrenaline, noradrenaline, growth hormone, IL-6, and IL-8 increased after each exercise and showed the significant difference. Subjective fatigue and the value of lactic acid, and IL-6 showed significant positive correlations. These results suggest that lactic acid, and IL-6 may become an index of fatigue in this exertion model.<br>

A DIGE PROTEOMIC ANALYSIS FOR LOW-INTENSITY EXERCISE-TRAINED RAT SKELETAL MUSCLE / 体力科学

<b>Background:</b> Exercise training induces various adaptations in skeletal muscles. However, the mechanisms remain unclear. <b>Purpose:</b> Therefore, we conducted 2D-DIGE proteomic analysis, which has not yet been used for elucidating adaptations of skeletal muscle after low-intensity exercise training (LIT). <b>Methods:</b> For five days, rats performed LIT, which consisted of two 3-h swimming exercise with45-m rest between the exercise bouts. 2D-DIGE analysis was conducted on epitrochlearis muscles excised eighteen hours after the final training exercise. <b>Results:</b> Proteomic profiling revealed that, out of 681 detected and matched spots, 22 proteins exhibited changed expression by LIT compared with sedentary rats. All proteins were identified by MALDI-TOF/MS. <b>Conclusion:</b> The proteomic 2D-DIGE analysis following LIT identified expressions of skeletal muscle proteins, includingATPsynα, UQCRC1, dihydrolipoamide dehydrogenase, dihydrolipoamide acetyltransferase, that were not previously reported to change their expressions after exercise-training.

THE <i>ACTN3</i> R577X NONSENSE ALLELE IS UNDER-REPRESENTED IN ELITE-LEVEL JAPANESE ENDURANCE RUNNERS / 体力科学

<b>Background:</b> Although previous reports have shown a lower proportion of the ACTN3 XX genotype (R577X nonsense polymorphism) in sprint/power athletes compared with controls, possibly attributed to the importance of skeletal muscle function associated with alpha-actinin-3 deficiency, the findings on association between endurance athlete status and R577X genotype are equivocal. <b>Purpose:</b> The present study was undertaken to examine association of <i>ACTN3</i> R577X genotype with elite Japanese endurance athlete status. <b>Subjects and Methods:</b> Subjects comprised 79 elite Japanese endurance runners (E) who participated in competition at national level and 96 Japanese controls (C). We divided endurance runners into two groups, i.e., 42 national level runners (E-N) and 37 international level runners (E-I) who had represented Japan in international competition. R577X genotype (rs1815739) was analyzed by direct sequencing. Frequency differences of polymorphisms between athletes and controls were examined by Chi-square tests. <b>Result:</b> The R allele frequency tended to be higher in E group than in C group (P=0.066). When we divided E into two groups, the R allele frequency in E-I group was significantly higher than that in C group (P=0.046); whereas there were no significant differences between E-N and C groups (p=0.316). Then, the three genetic models were tested. In the additive genetic model (RR>RX>XX), there were significantly differences between E-I and C (P=0.038), but not the dominant (RR vs. RX+XX) and the recessive (RR+RX vs. XX) genetic models. <b>Conclusion:</b> R allele of the R577X genotype in the <i>ACTN3</i> gene was associated with elite Japanese endurance athlete status.

VALIDITY OF PREDICTION EQUATION OF BASAL METABOLIC RATE BASED ON FAT-FREE MASS IN JAPANESE FEMALE ATHLETES / 体力科学

The aim of the present study was to examine the validation of prediction equation of basal metabolic rate (BMR) in Japanese female athletes. The study population consisted of 122 Japanese female athletes (age 20.2 ± 1.3 years, height 162.5 ± 6.3 cm, body weight (BW) 57.4 ± 7.7 kg, and fat-free mass (FFM) 45.5 ± 5.1 kg). Body composition was estimated by using air displacement plethysmography (BOD POD System). BMR was measured by indirect calorimetry using dougras bag tequnique, and predicted BMR was calculated from different equations based on FFM. When compared with measured BMR, predicted BMR from the equation of Taguchi et al. (BMR (kcal/day)= 26.9×FFM (kg)+ 36) and equation of Owen et al. were not significantly different. Whereas, predicted values from equation of Japan Institute of Sports Sciences, National Institute of Health and Nutrition and Cunningham were significantly different from measured value. Estimation error and Total error were smaller in equation of Taguchi et al. and Owen et al., however, equation of Owen et al. had a larger estimation error in the subjects who was small body size (less than 42kg) or large body size(more than 69kg). Furthermore, newer equation of Taguchi et al. (BMR=27.5×FFM+5) was developed from the pool data (n=205) in the present study. Standard error of estimation (SEE) of this equation was smaller than the equation of Taguchi et al., and systematic error was hardly observed.In conclusion, the newer equation of Taguchi et al. developed from measured BMR of Japanese female athletes was useful to predict BMR.

PREDICTION MODELS OF SARCOPENIA IN JAPANESE ADULT MEN AND WOMEN / 体力科学

The purpose of this study was to develop prediction models of sarcopenia in 1,894 Japanese men and women aged 18-85 years. Reference values for sarcopenia (skeletal muscle index, SMI; appendicular muscle mass/height², kg/m²) in each sex were defined as values two standard deviations (2SD) below the gender-specific means of this study reference data for young adults aged 18-40 years. Reference values for predisposition to sarcopenia (PSa) in each gender were also defined as values one standard deviations (1SD) below. The subjects aged 41 years or older were randomly separated into 2 groups, a model development group and a validation group. Appendicular muscle mass was measured by DXA. The reference values of sarcopenia were 6.87 kg/m² and 5.46 kg/m², and those of PSa were 7.77 kg/m² and 6.12 kg/m². The subjects with sarcopenia and PSa aged 41 years or older were 1.7% and 28.8% in men and 2.7% and 20.7% in women. The whole body bone mineral density of PSa was significantly lower than in normal subjects. The handgrip strength of PSa was significantly lower than in normal subjects. Stepwise regression analysis indicated that the body mass index (BMI), waist circumference and age were independently associated with SMI in men; and BMI, handgrip strength and waist circumference were independently associated with SMI in women. The SMI prediction equations were applied to the validation group, and strong correlations were also observed between the DXA-measured and predicted SMI in men and women. This study proposed the reference values of sarcopenia in Japanese men and women. The prediction models of SMI using anthropometric measurement are valid for alternative DXA-measured SMI in Japanese adults.

AMOUNT AND INTENSITY OF PHYSICAL ACTIVITY IN RELATION TO CARDIORESPIRATORY FITNESS IN JAPANESE MIDDLE-AGED AND ELDERLY MEN / 体力科学

PORPOSE: This study aimed to investigate the relation between cardiorespiratory fitness(CRF) and physical activity, especially vigorous physical activity, in Japanese middle-aged and elderly men.METHODS: Eighty-five men aged 30-69 years participated in this study. CRF was assessed by measuring the maximal oxygen uptake based on weight (VO₂max/wt) in an incremental test on a bicycle ergometer. METs·h/week was measured as the parameter of physical activity by using accelerometers. We defined the amount of physical activity higher than 3 METs as “Physical activity ; PA”in this study. Then, PA was divided into “Moderate physical activity ; MPA”(higher than 3 METs and below 6 METs)and “Vigorous physical activity ; VPA”(higher than 6 METs).RESULTS : CRF was positively correlated with PA(r=0.318, P<0.01), MPA(r=0.230, P<0.05), and VPA(r=0.301, P<0.01) and negatively correlated with age(r=-0.607, P<0.001), BMI(r=-0.369, P<0.01), and waist circumference(WC)(r=-0.486, P<0.001). After adjusting for age and WC, the multiple regression analysis revealed that PA was positively correlated with CRF(P<0.01). VPA was positively correlated with CRF(P<0.05) after adjusting for age, WC, and MPA. MPA was not correlated with CRF in the case of adjusting for age and WC.CONCLUSION : This study suggested that physical activity higher than 3 METs was positively associated with cardiorespiratory fitness independently of age and waist circumference, and particularly vigorous physical activity may contribute to increased cardiorespiratory fitness in middle-aged and elderly men. Thus physically active life with maintenance of adequate waist circumference may help to prevent age-related decline in cardiorespiratory fitness.

Retraction: PREDICTION MODELS OF SARCOPENIA IN JAPANESE ADULT MEN AND WOMEN / 体力科学

The purpose of this study was to develop prediction models of sarcopenia in 1,894 Japanese men and women aged 18-85 years. Reference values for sarcopenia (skeletal muscle index, SMI; appendicular muscle mass/height2, kg/m2) in each sex were defined as values two standard deviations (2SD) below the gender-specific means of this study reference data for young adults aged 18-40 years. Reference values for predisposition to sarcopenia (PSa) in each gender were also defined as values one standard deviations (1SD) below. The subjects aged 41 years or older were randomly separated into 2 groups, a model development group and a validation group. Appendicular muscle mass was measured by DXA. The reference values of sarcopenia were 6.87 kg/m2 and 5.46 kg/m2, and those of PSa were 7.77 kg/m2 and 6.12 kg/m2. The subjects with sarcopenia and PSa aged 41 years or older were 1.7% and 28.8% in men and 2.7% and 20.7% in women. The whole body bone mineral density of PSa was significantly lower than in normal subjects. The handgrip strength of PSa was significantly lower than in normal subjects. Stepwise regression analysis indicated that the body mass index (BMI), waist circumference and age were independently associated with SMI in men; and BMI, handgrip strength and waist circumference were independently associated with SMI in women. The SMI prediction equations were applied to the validation group, and strong correlations were also observed between the DXA-measured and predicted SMI in men and women. This study proposed the reference values of sarcopenia in Japanese men and women. The prediction models of SMI using anthropometric measurement are valid for alternative DXA-measured SMI in Japanese adults.

DEVELOPMENT OF VO_2max PREDICTION MODELS FROM 3-MINUTE WALK TEST / 体力科学

The purpose of the study was to develop new VO_2max prediction models for Japanese men using a 3-minute walk test. One hundred and twenty-seven Japanese men aged from 20 to 69 years were recruited as subjects of the present study. Maximal oxygen uptake (VO_2max) was measured with a maximal incremental test on a bicycle ergometer. The prediction models were derived using data of age, 3-minute walking distance (3MWD), and either BMI, waist circumference (WC), or %Fat. This data was cross-validated by using PRESS cross-validation procedures. 3MWD was significantly related to VO_2max (<i>r</i> = 0.54, P<0.001). The multiple correlation coefficients for the BMI, WC, and %Fat models, respectively, were 0.81, 0.82, and 0.85. The standard error of estimate (SEE) was 4.5, 4.4, and 4.1 ml·kg^-1·min^-1, respectively, for the BMI, WC, and %Fat models. All regression models demonstrated a high level of cross-validity supported by the minor shrinkage of the coefficient of determination and increment of SEE in the PRESS procedure. This study demonstrated that 3MWD was useful for predicting VO_2max accurately using VO_2max prediction models for Japanese men. The new non-exercise prediction equations derived in this study are applicable to estimating VO_2max in Japanese adult men.

METABOLIC SYNDROME RISK FACTORS IN RELATION TO AEROBIC FITNESS IN JAPANESE MIDDLE-AGED AND ELDERLY PEOPLE －ANALYSIS BASED ON “EXERCISE AND PHYSICAL ACTIVITY REFERENCE FOR HEALTH PROMOTION 2006 (EPAR2006)”－ / 体力科学

PORPOSE: This study aimed to compare the prevalence of metabolic syndrome (MS) risk factors and its components in different levels of aerobic fitness established by “Exercise and Physical Activity Reference for Health Promotion 2006 (EPAR2006)” in Japanese middle-aged and elderly people.METHOD: Men (n=102) and women (n=133), aged 30-69yrs, participated in this study. The prevalence of MS risk factors was evaluated as the number of MS risk factors, according to the diagnostic criterion for Japanese-specific MS. Aerobic fitness was quantified as maximal oxygen uptake (VO₂max). Subjects were classified into the three groups by aerobic fitness level based on “Reference values” and “Reference range” established in EPAR2006; 1) High fitness group (H); VO₂max (mL/kg/min) is higher than “Reference values”, 2) Medium fitness group (M); VO₂max is below “Reference values” but within “Reference range”, 3) Low fitness group (L); VO₂max is lower than “Reference range”.RESULTS: In men, M and L groups showed significantly higher frequency of risk factors for MS than H group (H: 1.09±0.98, M: 1.81±1.07, L: 2.27±0.70, P＜0.01). In women, L group showed significantly higher frequency of risk factors for MS than H and M groups (H: 0.57±0.80, M: 0.81±1.01, L: 1.53±1.07, P＜0.01).CONCLUSION: These results suggest that higher MS risk appears when the VO₂max is lower than “Reference values” in men, and below “Reference range” in women, and that particularly, men with low aerobic fitness have higher MS risk.

EFFECTS OF CARBONATED AND NONCARBONATED BEVERAGE INTAKES IN RESPONSE TO PROLONGED CYCLE ERGOMETER EXERCISE / 体力科学

Athletes have been instructed to refrain from taking carbonated beverages in the sports world, but the mechanism has not been clear. The purpose of this study was to clarify how physiological and biochemical evaluation are affected by taking a 10% CHO carbonated beverage after cycle ergometer (60 min, 60% VO₂max). Seven subjects consumed a carbonated or noncarbonated (10% carbohydrate) beverage after exercise. No differences were observed in concentration of glucose, insulin, free fatty acids, K and Na in serum from carbonated beverage compared with noncarbonated beverage intakes after exercise.These results indicate that carbonated beverage did not affect the changes of physiological and biochemical parameter after prolonged exercise, and it could be more refreshing and stimulate taste rather than noncarbonated beverage, but seemed to be hard to drink immediately after exercise because it made subjects feel as if having drunk more than they did.

BASAL METABOLIC RATE AND ITS DETERMINANTS IN POSTMENOPAUSAL WOMEN / 体力科学

The basal metabolic rate (BMR) of 70 postmenopausal women (age: 60.6±4.2 yrs., height: 154.9±5.2cm, body weight (BW) : 52.7±6.2kg; mean ±SD) was evaluated in relation to body composition (body fat mass (FM) : 17.3±3.9kg, lean body mass (LBM) : 35.3±3.6kg) . BMR was 1, 148±126kcal/day, 21.9±2.2kcal/kgBW/day, 32.7±3.2kcal kgLBM/day in all subjects. BMR (kcal/day) significantly correlated with BW (r=.635, p<0.001) and LBM (r=.598, p<0.001) . When divided into two groups, (lower %fat group (LF; <35%fat) and higher %fat group (HF; ≥35%fat) ), BW and FM were significantly higher in HF than in LF (BW: 56.6±6.4 vs 51.0±5.3 kg, FM: 21.7±2.8 vs 15.5±2.7 kg, p<0.001, respectively) . No difference was observed in LBM between the two groups (34.9±3.9 vs 35.5±3.5 kg) . BMR (kcal/kgBW/day) was lower in HF than in LF (21.0±1.8 vs 22.3±2.3, p<0.05), but HF group had higher BMR in terms of kcal/kgLBM/ day than LF (34.0±3.1 vs 32.1±3.1, p<0.05) . Multiple regression analysis was performed to predict BMR. A single predictor LBM and a pair of predictors LBM and FM explained 35.7% and 42.7% of the variance of BMR. This study suggested that a decrease in LBM is a major factor in affecting the reduction of BMR in postmenopausal women, whereas FM gained after menopause could be considered to have metabolic activity related to BMR.

Effects of Swimming Exercise on Maximal Aerobic Capacity and Plasma Lipid-Lipoprotein Profile of Postmenopausal Women / 体力科学

This study was designed to evaluate effects of long-term swimming training on maximal aerobic capacity and sernm lipid and lipoprotein profile of postmenopausal women. In the first study, 12 swimming-trained postmenopausal women (age: 58±3 yrs, BMI : 22± 2 kg/m<SUP>2</SUP>, training distance : 3.6±1.6 km/wk, mean±SD) were compared cross-sectionally with 50 age-matched untrained women (58±5 yrs, 23±2 kg m<SUP>2</SUP>) . Swimming-trained women had higher maximal oxygen uptake (Vo2max) than untrained (34± 5 vs. 30± 5 ml/kg/min, P<0.05) . Serum total- and HDL-cholesterol (T-C and HDL-C) and triglyceride (TG) concentrations in swimmers were similar to those in untrained (T-C: 232±23 vs. 220±44 mg/dl, HDL-C : 69±15 vs. 72±17 mg/dl, TG : 83±21 vs. 99±67 mg/dl) . On the other hand, swimmers had higher serum LDL-cholesterol concentrations (LDL-C) than untrained women (161±28 vs. 138±25 mg/dl, P<0.05) . The second study was conducted to test the effects of a 2-year swimming program on Vo2max and serum lipid and lipoprotein concentrations of postmenopausal untrained women. After the swimming program 10 trained women (age : 59±7 yrs, BMI : 23±3 kg/m<SUP>2</SUP>, Vo2max : 30± 3 mlikg/min at baseline, training condition : one hour session, frequency: 1.5±0.4 times/week during the program) and 12 untrained women (60± 5 yrs, 23± 3 kg/m<SUP>2</SUP>, 29± 5 ml/kg/min at baseline) were retested. No change in BMI was observed in the two groups. At the 2-year follow-up, the trained women increased Vo2max (34± 5 ml/kg/min, P<0.05), whereas no change in Vo2max was observed in the untrained women (30± 5 ml/kg/min) . No changes occurred in concentrations of T-C (Trained : 238±25 233±21 mg/dl, Untrained : 236±20 236±32mg/dl), HDL-C (Trained : 70 ± 15→74 ± 16 mg/dl, Untrained: 69 ± 15→69 ± 14 mg/dl), LDL-C (Trained : 150 ±29 144±27mg/dl, Untrained : 144±15→145±23mg/dl), and TG (Trained : 90±32 74±25 mg/dl, Untrained : 115±81 106±52mg/dl) . These results suggest that although a long-term swimming program can increase maximal aerobic capacity, favorable changes in sernm lipids or lipoproteins can not be expected for postmenopausal women.

The Effects of Swimming Exercise on Bone Mineral Density in Postmenopausal Women / 体力科学

In this study, we investigated the effects of a 2-year swimming program on suppressing bone loss in postmenopausal women. There were 22 subjects who participated in the swimming program (mean age 59.5 yr) and 19 controls (mean age 59.3 yr) . The program consisted of one-hour exercise sessions ; and the swimmers had on average 1.5 sessions per week. BMD at the lumbar spine (L2-L4) and proximal femur (neck, trochanter, and Ward's triangle) were measured by dual X-ray absorptiometry (DXA) ; and leg extensor power was measured using a dynamic leg extensor power rig. All the measurements were taken at baseline, 1 and 2 years. Height, weight, calcium intake and daily activity profiles were similar between the two groups, and these changed little throughout the experiment. In regard to leg extensor power, the swimming group had a significant increase at 1 and 2 years. At 2 year, the swimming group demonstrated 4.4%, 5.7% and 3.4% increases in BMD at the femoral neck, trochanter and Ward's triangle, respectively, while the control group showed slight decreases of BMD at the femoral neck (-0.2%) and Ward's triangle (-1.4%) . Significant differences in the rate of change in BMD at each site were observed between the two groups. The swimming group showed a decrease in lumbar spine BMD, as did the control group and the rate of the decline did not differ between the two groups. This study suggests that a 2-year swimming program for postmenopausal women can induce the beneficial effects of retarding bone loss at the proximal femur site and increasing leg extensor power.

Effects of activity level and type of muscle on glucose transporter protein concentration / 体力科学

In this study, we investigated the possibility that GLUT4 protein concentration and mitochondrial enzyme activity is coregulated by muscle contractile activity. In the first experiment, male rats were trained by treadmill running or swimming for 3 wks and training effects in upper-and hind-limb muscle were investigated. Treadmill training program induced increases of 30% in citrate synthase activity, 51% in hexokinase activity, and 35% in GLUT4 protein concentration in hind-limb soleus muscles without causing training effects in upper-limb epitrochlearis muscles. On the other hand, swimming training program induced increases of 67% in citrate synthase activity, 139% in hexokinase activity, and 89% in GLUT4 protein concentration in epitrochlearis muscle without causing training effects in soleus muscles. These results suggest that muscle contractile activity which raises mitochondrial enzyme activity increases GLUT4 protein concentration in skeletal muscle. In a second set of experiment, we investigated relationship between muscle GLUT4 protein concentration and mitochondrial enzyme activity by use of the various type of rat muscles (soleus, plantaris, red gastrocnemius, white gastrocnemius, epitrochlearis and heart), which possese different contractile activity level. Significant correlation was observed between GLUT4 protein concentration and citrate synthase activity among different muscles (r=0.936) . They suggest that muscle GLUT4 protein concentration and mitochondrial enzyme activity level may be coregulated according to muscle contractile activity level.

Effects of local muscle activity on glut 4 concentration in skeletal muscle / 体力科学

In the present study, we examined whether GLUT4 concentration in rat skeletal muscle is dependent on local muscle activity level or not. In ten male Sprague-Dawley rats, one side of gastrocnemius muscle was tenotomized, and the other side contralateral muscle was treated sham operation as a control. Gastrocnemius and plantaris muscles were excised from both legs at the five weeks after surgery. After the muscles were weighed, GLUT 4 concentration and citrate synthase (CS) activity were measured. The results are summarized as follows:<BR>In gastrocnemius muscle, tenotomy induced decreases of 25% in muscle weight, 16% in CS activity, and 25% in GLUT 4 concentration as compared with the control muscle. These data suggest that although extramuscular environment is similar, different GLUT 4 concen-tration in both muscles is induced by different muscle activity level. Therefore, it is con-cluded that muscle activity level regulates GLUT 4 concentration in skeletal muscle. In over-loaded synergistic plantaris muscle, muscle weight and GLUT 4 content per whole muscle were increased by 18% and 17%, respectively, but GLUT 4 concentration and CS activity were not changed as compared with the control muscle. These data could be interpreted that GLUT 4 concentration and mitochondrial oxidative enzyme activity in skeletal muscle are coregulated.

Nutritional profiles in middle-aged female runners / 体力科学

Nutritional profiles in middle-aged trained and untrained women were compared both before and after menopause. Subjects were assigned to one of four groups : (1) pre-menopausal trained (Pre-T: n=14, aged 43±5 years, running distance 56±27 km/week, Vo<SUB>2</SUB>max 49±4m<I>l</I>/ kg/min, mean±SD), (2) pre-menopausal untrained (Pre-UT: n=25, 42±5 years, 34±5 m<I>l</I>/kg/ min), (3) post-menopausal trained (Post-T: n=19, 53±3 years, 49±17 km/week, 42±6 m<I>l</I>/ kg/min), (4) post-menopausal untrained (Post-UT: n=26, 54±3 years, 31±3 ml/kg/min) . There were no significant differences in hematocrit (range 38.7 to 39.3%), hemoglobin (12.8 to 13.1 g/d<I>l</I>) and total protein (6.9 to 7.1 g/d<I>l</I>) among the four groups. Serum iron concentrations in the post-menopausal women (Post-T: 97±30μg/d<I>l</I>, Post-UT: 106±29μg/d<I>l</I>) were relatively higher than in the pre-menopausals (Pre-T: 85±35 pg/d<I>l</I>, Pre-UT: 78±33 pg/d<I>l</I>) . Mean total iron binding capacity in Post-UT (326 pg/d<I>l</I>) was lower than other groups (352 to 361 pg/d<I>l</I>) . Higher serum ferritin levels were observed in the post-menopausal women (Post-T : 35.8±27.5 ng/m<I>l</I>, Post-UT : 60.4±47.1 ng/m<I>l</I>) than the pre-menopausals (Pre-T: 18.3±13.1 ng/m<I>l</I>, Pre-UT: 16.6±10.7ng/m<I>l</I>) . Intake levels of the four groups with regard to the major nutrients were sufficient as compared with the recommended dietary allowance appropriate for age, sex and physical activity level. Intakes of calcium, iron and vitamins B<SUB>1</SUB>, B<SUB>2</SUB> and niacin were higher in the trained groups than in the untrained. Regularly performed endurance exercise resulted in higher protein and iron intakes associated with higher energy intakes both before and after menopause. These results suggest that nutritional status of middle-aged women who regularly perform vigorous endurance running could be adequate for maintaining their health in a good state.

Effects of different types of physical training on insulin action in human peripheral tissues. Use of the euglycemic clamp technique / 体力科学

Physical training has been shown to improve glucose tolerance and insulin action in peripheral tissues. In the present study, regular (R) and high (H) -dose euglycemic clamp procedures were performed to determine the effects of different types of physical training on insulin action (sensitivity/responsiveness) in 10 long-distance runners (LR), 10 weight-lifters (WL) and 12 healthy controls (HC), The amount of infused glucose (glucose metabolism, GM) during euglycemic clamping is a measure of the peripheral tissue sensitivity and/or responsiveness to insulin. For R clamping, when GM was calculated per unit body weight (BW), GM in LR (11.92±1.22 mg/kg BW·min) and WL (9.28±0.63 mg/kg BW·min) was significantly (P<0.05) higher than that in HC (7.44±0.39 mg/kg BW·min) . When calculated per unit lean body mass (LBM), LR (15.07±1.56 mg/kg LBM·min) differed from HC (9, 15±0.59 mg/kg LBM·min, P<0.05), whereas the value in WL (11.50±0.93mg/kg LBM·min) was identical to that in HC. For H clamping, there was no significant change in these three groups when GM was calculated per unit BW or LBM. These results suggest that enhancement of insulin action by physical training is due to an increase in insulin sensitivity, rather than to an increase in insulin responsiveness, and that aerobic exercise, for example long-distance running, is more effective for the improvement of decreased sensitivity to insulin, which is observed in patients with simple obesity and diabetes, than anaerobic exercise such as weight-lifting.

Nutritional status of older endurance athletes / 体力科学

This study was designed to evaluate nutritional status of older endurance runners (age ; 62.5±2.5 yr., weight ; 53.8±4.2 kg, %fat ; 12.0±2.1%, mean±SD) by comparing with agematched sedentary individuals (63.6±3.5 yr., 58.4±9.1 kg, 15.6±4.0%) and middle-aged long distance runners (35.2±3.1 yr., 61.2±5.6 kg, 11.8±1.9%) . Average training distance of the older runners was a half of that of the middle-aged runners (44 vs. 85 km/week) . Maximal oxygen uptake in the older runners was significantly higher than in the older sedentary controls, but lower than in the middle-aged runners (50.4±4.1 vs. 30.6±3.5 vs. 64.0±2.2 ml/kg/min, respectively) . No differences were observed in the concentrations of serum albumin, serum iron and blood hemoglobin among the three groups. Intake levels of the three groups with regard to the major nutrients were sufficient as compared with the recommended dietary allowance appropriate for age, sex and physical activity level. Total caloric intake in the older runners was not remarkably higher than in the older controls in terms of kcal/day (2, 430 vs. 2, 230), but was significantly higher in terms of kcal/kg wt/day (45.5 vs. 38.9) . Percents to the total caloric intake of protein (15.2%), fat (25.4%) and carbohydrate (52.6%) in the older runners were almost identical to the other two groups. Ratios of animal to total in protein and fat were not significantly different among the groups. The intakes of calcium, iron, and vitamins A, B1, B2 and niacin were higher, but statistically not significant, in the older runners than in the older controls. These results suggest that nutritional status of older endurance runners is adequate for maintaining their health in a good state while keeping their active lifestyle.