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.

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.

A survey comparing nutritional status and exercise training programs between adolescent Japanese and Chinese athletes / 体力科学

The nutritional status and exercise training programs were compared between adolescent Japanese and Chinese athletes who belonged to the top schools for track and field and basketball in their respective countries. The mean energy intake was about two times greater in Chinese athletes than in their Japanese counterparts. Chinese athletes consumed 1.5-2.0 times more carbohydrate, 1.9-2.3 times more protein, 3.5-7.5 times more calcium, 2.9-3.7 times more iron, 1.72-2.2 times more vitamin B1 and 1.3-1.8 times more vitamin B<SUB>2</SUB>. Almost all the Chinese athletes consumed more than the Recommended Dietary Allowance standards for energy, protein, calcium, iron and vitamins A, B<SUB>1</SUB>, B<SUB>2</SUB> and C, while many Japanese athletes did not meet them except for vitamin A and C. The Japanese athletes had more inadequate training schedules, insufficient weight training, and unsatisfactory amount and intervals of rest. These results indicate that Japanese athletes have certain deficiencies in their comprehensive training programs in consideration to nutrition, exercise and rest.