This study examined tennis serving in older adult tennis players. Twenty-two older adults, divided into younger and older halves, were videotaped serving five “first” serves. Dominant shoulder flexibility also was measured. From the videotape, servers were classified into developmental levels and their resultant ball impact velocity was calculated. An Age × Gender (2 × 2) mixed model MANOVA yielded no significant differences between the age groups or between men and women in flexibility, ball impact velocity, or movement pattern. A few combinations of the developmental levels of elbow and forearm/racket action were used by the majority of servers. Regular practice might consolidate older adults in these attractor movement patterns, making them more resilient to change than with less practiced skills. These results suggest practice in older adulthood favorably affects performance by resulting in consistency of movement pattern and maintenance of movement pattern, flexibility, and ball impact speed.
Kathleen M. Haywood and Kathleen Williams
Kathleen Williams, Kathleen M. Haywood and Mary A. Painter
Both environmental and biological factors have been cited to explain large gender differences in throwing. Because differences are observed as early as three years, some researchers have suggested biological differences may be a primary factor (Nelson et al., 1986). To explore the contribution of these factors more carefully, three groups of children, 7-8 years, 9-10 years, and 11-12 years, were videotaped performing ten forceful overarm throws each with their dominant and nondominant hands. Resultant ball velocities were computed across all trials for each hand. Five trials for each arm, for each participant were categorized using Roberton’s (Roberton & Halverson, 1984) movement components for the overarm throw. Overall significant age differences were obtained for ball velocities for both dominant and nondominant arms, but gender differences were demonstrated only for the dominant arm. Ball velocity differences for the nondominant arm were not evident. Minimal differences in form occurred for the nondominant arm. When the nondominant arm exhibited coordination patterns and performances typical of an unpracticed performer, we suggest that nonbiological factors are important in explaining the large gender differences in throwing widely noted in the literature.
Linda M. Gagen, Kathleen M. Haywood and Steven D. Spaner
This study tested the hypothesis that scaling environmental objects can afford differently sized individuals the opportunity to make similarly effective movements with that object. Four similar tennis rackets were scaled to provide consistent differences in length, weight, and grip size. Children between 4 and 10 years of age were asked to strike with each racket for speed and accuracy. A significant relationship existed between body size and strength and the ability to both generate racket head speed and control the racket for an accurate strike; racket size and weight, however, were not significant factors in the ability to swing effectively.