This study compared the start motions (n = 60) in a 1km time trial and a 250 m time trial for competitive cyclists. Significant correlations were observed between 10 m time and 1 m time (r=0.866,P<0.001) and between 10 m time and 195 m time (r = 0.758,P < 0.001). The hip horizontal velocity at stopper release of starting equipment correlated negatively with 1 m time (r = - 0.897,P < 0.001), indicating that the starting technique before stopper release is one of the most important factors for time trial performance under a static condition. Regarding start motion, the angle of the elbow joint and shoulder joint in upper group at stopper release were significantly smaller than those in lower group. Furthermore, the horizontal length from the center of crank and hip for upper group at stopper release was significantly smaller than that of lower group. These findings indicate that it is important to increase the horizontal velocity of cyclists before the stopper release and to start pedaling on the center of the crank at the stopper release in order to enhance the pedal pressure.

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The present study examined the influence of the duration of a conditioning contraction inducing postactivation potentiation on the extent of increase in subsequent maximal voluntary concentric torque. Nine male subjects performed a 6 s or 14 s maximal voluntary isometric plantar flexion as the preceding conditioning contraction. Before and immediately after the conditioning contraction, the twitch torque and maximal voluntary concentric torque were recorded. The twitch torque significantly increased in the 6 s and 14 s conditions. The twitch torque after the 14 s conditioning contraction was significantly larger than that after the 6 s conditioning contraction (p < 0.05). Electromyogram recodings indicated that central fatigue was larger in the 14 s condition. These results suggest a tradeoff of the negative (fatigue) and positive (potentiation) effects that can mask the resultant increase in voluntary torque, when the conditioning contraction is performed beyond a certain duration.

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The present study examined the influence of shot training with a ring that narrowed the diameter of the basket during the performance of a free throw by 12 college basketball players. The training group attempted 30 shots in one session 5 times per week for 4 weeks. The number of failed attempts was decreased in this group compared with a control group who shot at a regular basket. Moreover, differences in projection angles were decreased by training. It was suggested that the free throw training at a ring with a narrowed diameter helps the player to shoot more into the center of the ring with higher repeatability.

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The purpose of this study was how the physique influenced to the contents of batting by the difference of the athletic level in baseball.
Total data was collected from 1245 elite baseball players, who were selected from five different athletic level groups (high school baseball, college baseball, industry league baseball, Nippon Professional Baseball, and Major League Baseball).
Body height and weight and batting contents such as batting average, the slugging percentage and the strikeout rate were recorded for each player. Moreover, relationships among body height and weight and batting contents were examined in five groups.
As a result, body weight was strongly related with the slugging percentage. In professional players, strikeout rate was positively related with body height. However such tendency was not shown in amateur players. In each group, batting average indicated positive relation to slugging percentage and negative relation to strikeout rate.
As far as relation between slugging percentage and strikeout rate, negative tendency was shown only for amateur players.
It was suggested that the physique influenced the characteristics of batting contents showed from respective athletic level groups.

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The present study conducted a longitudinal investigation of the characteristics of blood glucose kinetics in elite Japanese soccer players by analyzing blood glucose kinetics during an incremental running test. Ten elite soccer players performed an incremental running test in January and August of 2009 and January of 2010. Blood lactate,blood glucose, oxygen consumption, lactate threshold (LT), glucose threshold (GT) and maximal oxygen consumption (VO₂max) were measured during each test. LT was observed in all subjects during all tests, and significant changes in LT and VO₂max were not observed. However, the number of GT observations fluctuated between the training periods as 5, 9 and 3, respectively, and a significantly higher observation rate was found during the season. Our results demonstrate that GT cannot always be determined in elite Japanese soccer players. Furthermore, even the well-known endurance capacity indicators, LT and VO₂max, do not change significantly after specific training during the season; blood glucose kinetics could change during training, which affects the number of GT observations.

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The purpose of this study was to investigate the effects of high intensity interval training using a Canadian canoe ergometer under normal as well as hypoxic environment in national or collegiate championship level canoeists. Nine men (N; normal training group) performed high intensity interval training at sea level, whereas the other nine men (H; hypoxic training group) trained in low-oxygen environment (equivalent to 2000-3000m altitude) using a normobaric hypoxic room. The subjects performed this ergometer training for 3 or 4 days per week, over a 3 week period. This ergometer training was incorporated into their daily training in a college canoe team. After the training period, aerobic working capacity (maximal oxygen uptake), anaerobic working capacity (10-second maximal paddling power), performances at 200m and 500m time trial improved significantly in both groups. Furthermore, the improvement of 200m performance was larger in H group than N group. These results suggest that additional canoe ergometer training under normal or hypoxic environment improves both anaerobic and aerobic working capacity, and results in the improvement of 200m and 500m performance. Moreover, if the training is performed under hypoxic environment, 200m performance will improve larger than that of sea level training.

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The aim of this study was to analyze the timing of upper and lower limbs during standing long jump in school children by biomechanics. One hundred twenty eight elementary school boys (6-11yrs) and ten male adults participated in this study. Subjects performed standing long jump as far as possible, the motion of the body segments was monitored and analyzed using a 2-D video analysis system. We focused on shoulder, hip and knee joints. RESULTS: The velocity of extension and flexion on shoulder joint increase with age. The flexion time of shoulder joints decrease from 1st grade to 4th grade, the extension time of hip joints increase from 4th grade to adults, but no significant differences were observed at the flexion time of knee joints. The time (SHT) from the shoulder's flexion moment (SFM) to the hip's extension moment (HFM) decreases with age. SFM and HEM in the 6th grade and adults were observed almost in the same time. Performance was significantly related to SHT (r= - 0.577,p<0.001). CONCLUSION: The timing of upper and lower limb during standing long jump was changing during elementary school children. We should know these characteristics when we teach standing long jump.

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