Comparison of base running in baseball players and track-and-field athletes

This study aimed to examine the relationship be-tween sprint ability and base running of baseball players and track-and- field (T&F) athletes, and to identify the association between sprint ability and running skill on base running. The subjects were 25 male university baseball players and 15 male T&F athletes without baseball experience. The straight sprint time of 54.8 m and 109.6 m (corresponding to the distance to second and home) was measured. In the home run test, the times to reach each base were measured. In the second base run test, the actual running distance and 3 m section time around the first base were measured. Base running efficiency was obtained by dividing the base running time by the straight sprint time. T&F athletes showed higher values than baseball players only in the 109.6 m straight sprint time (P < 0.05, ES=1.35). Baseball players were significantly superior to T&F athletes in terms of base running efficiency. As for 3 m section times, baseball players showed significant and higher values. The straight sprint time showed significant and high correlations (r = 0.87, 0.90) between the 109.6 m run and the run home and be-tween the 54.8 m run and the second base run in baseball players, but not in T&F athletes. It was found that superior sprint ability does not always lead to good base running. In base running, it is important to run outward to some extent. In particular, the skill acquisition of base running in 3 m sections around the base will contribute to shortening base running time.

Evaluating the effects of open/closed eyes and age-related differences on center of foot pressure sway during stepping at a set tempo

This study aimed to examine the effects of open/ closed eyes and age difference on Center of Foot Pressure (COP) sway during stepping. The subjects were 87 healthy males aged 10 - 80 years. COP was measured 20 times when subjects stepped on two force plates (left and right) at a rate of 60 steps/min. The evaluation parameters selected were: total trace length, velocity, circumference, rectangular area,left-right width, and front-back width. The former four of these parameters were found to be significantly lower with eyes open than eyes closed in 80-year-old subjects, while the last parameter was significantly lower with eyes open in 10-year-old subjects. In 70- and 80-year-old subjects with eyes open, circumference was greater than that in 10- and 40 - 60-year-old subjects;their rectangular area was greater than that in 50- and 60-year-old subjects;and, their front-back width was greater than that in 10- and 30 - 60-year-old subjects. With eyes closed, circumference, rectangular area, left-right width, and front-back width in 80-year- old subjects, were greater than those in 10 - 70- year-old subjects. The front-back width during stepping with eyes closed was greater in 70- and 80-year-old subjects than in 30 - 50-year-old subjects. The Romberg quotient for all COP sway parameters revealed no significant age-related differences. From our findings, a difference in body sway was observed in 80-year-old subjects (with eyes open/closed) when compared with the other age groups. In addition, the extent of sway varied little among 80 year-old- subjects have greater body sway during stepping, particularly with eyes closed.