Age-related differences in postural control in response to a relatively large deceleration resulting from postural disturbance were investigated in eight normal elderly men (age range 67-72 years) and eight young men as controls (age range 19-22 years) using a moving platform. Data were obtained for the hip, knee and ankle angles, position of the centre of foot pressure (CFP), head acceleration, and muscle activity of the leg muscles. The elderly subjects had slower and larger ankle and hip joint movements, and CFP displacement in response to the disturbance compared to the young controls. The elderly subjects also had a delayed occurrence, and greater magnitude of peak acceleration of head rotation than did the young subjects. For the elderly subjects, the CFP was closely related to angular changes in the hip joint movement, but not to those of the ankle and knee joint movements. For the young subjects, on the other hand, the CFP was significantly correlated with angular change in the ankle joint. Cocontraction of the tibialis anterior and gastrocnemius muscles was observed in the elderly subjects. The results indicated that a movement pattern for postural correction in the elderly adults was different from that of the young adults. The elderly relied more on hip movements while the young controls relied on ankle movements to control postural stability.

BackgroundTo establish Japanese children’s estimated energy requirements, total energy expenditure (TEE) data measured using the doubly labeled water (DLW) method is needed. This study aimed to 1) obtain basic TEE data from Japanese children measured using DLW (TEEDLW), 2) compare TEEDLW with TEE estimated by various estimation formulas to calculate their accuracy, and 3) develop a new equation to estimate TEE using body composition and pedometers.MethodsTEE was measured using DLW in 56 10- to 12-year-old Japanese children (33 boys, 23 girls). Physical activity level (PAL) was calculated by dividing TEEDLW by estimated resting energy expenditure. To assess their physical activity, participants wore pedometers during the 7-d DLW period. Total body water was calculated from 2H and 18O; fat-free mass (FFM) and fat mass (FM) were then determined.ResultsIn boys and girls of normal weight, TEEDLW was 2067 ± 230 kcal/d and 1830 ± 262 kcal/d, respectively. Average PAL was 1.58 ± 0.17. FFM was strongly related to TEE (r = 0.702, p < 0.01). After adjusting for FFM and FM, step count was significantly associated with TEE (r = 0.707, p < 0.01). The TEE estimation formula used in the Dietary Reference Intakes (DRI) for the United States and Canada estimated TEEDLW with high accuracy (bias: 2.0%) in both sexes. We developed new equations for TEE consisting of FFM and step count, which accounted for 68% and 65% of TEE variance in boys and girls, respectively: boys, 47.1 × FFM (kg) + 0.0568 × step count (steps/d) – 122, and girls, 55.5 × FFM (kg) + 0.0315 × step count (steps/d) - 117.ConclusionsThe TEE in 10- to 12-year-old Japanese children measured using DLW was approximately 7% lower for boys and 12% lower for girls compared to the current Japanese DRI. If PAL can be accurately determined, the equation in the DRI for the United States and Canada may be applicable to Japanese children. In addition, TEE could be predicted using FFM and step count.

The purpose of this study was to examine the effects of 2 different training regimens, continuous (CT) and interval (IT), on endurance capacity in maximal intermittent exercise. Eighteen lacrosse players were divided into CT (n = 6), IT (n = 6), and nontraining (n = 6) groups. Both training groups trained for 3 days per week for 15 weeks using bicycle ergometers. Continuous training performed continuous aerobic training for 20-25 minutes, and IT performed high-intensity pedaling comprising 10 sets of 10-second maximal pedaling with 20-second recovery periods. Maximal anaerobic power, maximal oxygen uptake (V(O2max)), and intermittent power output were measured before and after the training period. The intermittent exercise test consisted of a set of ten 10-second maximal sprints with 40-second intervals. Maximal anaerobic power significantly increased in IT (p

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The purpose of this study was to make clear the characteristics of physical fitness and life-style of boys and girls in the most superior and inferior groups on physical fitness level. About 29,000 boys and girls were measured their physical fitness and motor performances, body height and body weight and were also estimated the levels of physical activities, frequency of breakfast intake, sleeping hours and watching TV hours. The physical fitness and motor performances of the most superior group, as the results, showed higher values of 40-70% in boys and 60-85% in girls than those of the inferior group. BMIs in the both groups at junior high school period showed similar values each other and were higher than that of the average fitness group. These results suggest that it must pay attention to estimate a development of body composition by BMI. The most inferior group was also characterized with low physical activity levels and irregular breakfast intake and sleeping hours in their life style.