RESUMEN

BACKGROUND: It is firmly established that achieving a high ball speed during the execution of groundstrokes represents a relevant factor for success in tennis. However, little is known about how plantar pressure changes as post-impact ball speed is increased during open and square stance groundstrokes. The objective of the study was to determine how tennis players change the plantar pressure in each foot when they execute open versus square stance forehand groundstrokes in order to increase post-impact ball speed. METHODS: Fifteen healthy female tennis players with ITN 2 or better (mean age: 22.7 ± 7.8 years) participated in this study. The players performed open and square stance longline forehand groundstrokes (topspin) at the following four post-impact ball speed levels: 80 km/h, 90 km/h, 100 km/h, and vmax. Flexible pressure-detecting insoles were used to measure plantar pressure in each foot [i.e., dominant (equals the stroke arm) and nondominant]. RESULTS: The repeated measures ANOVA showed significant stance style × foot dominance interactions and post-hoc analyses revealed larger maximal and mean forces during open compared to square stance for the dominant but not non-dominant foot. Further, the ball speed × stance style × foot dominance interaction reached the level of significance and post-hoc analyses showed increased/decreased mean forces in the dominant/non-dominant foot during the square but not open stance when players increased their post-impact ball speed. CONCLUSION: Larger values in the open stance, but post-impact ball speed-adjusted values in square stance indicate different advantages in both styles, suggesting their situation-specific application.

RESUMEN

OBJECTIVE: Performing groundstrokes is a fundamental skill for tennis players. However, little is known about changes in plantar pressure when post-impact ball speed is increased during topspin and slice groundstrokes. The objective of the present study was to examine how elite (International Tennis Number ≤ 2) female tennis players (N = 15, mean age: 22.7 ± 7.8 years) change their plantar pressure in the dominant (equals the stroke arm) and non-dominant foot when executing topspin and slice longline forehand groundstrokes in order to increase post-impact ball speed (i.e., 80 km/h, 90 km/h, 100 km/h, vmax). RESULTS: The repeated measures analysis of variance revealed a significant ball speed × foot dominance interaction. Post-hoc analyses showed larger mean forces during topspin compared to slice groundstrokes for the dominant foot (p ≤ .026, d ≥ 0.34) but lower values for the non-dominant foot (p ≤ .050, d ≥ 0.28). Further, with increasing post-impact ball speed, increases in mean forces in both feet during topspin could be observed but only in the dominant foot during slice groundstrokes. Varying mean forces depending on the stroke type and foot dominance imply that specific physical exercises related to these two factors are necessary to optimise plantar pressure distribution.

Asunto(s)

Accidente Cerebrovascular , Tenis , Humanos , Femenino , Adolescente , Adulto Joven , Adulto , Pie , Fenómenos Biomecánicos , Ejercicio Físico

RESUMEN

Introduction: Achieving high ball speed during the execution of groundstrokes represents a performance-relevant factor in tennis. However, it is unclear how plantar pressure data undergo change during the execution of groundstrokes by tennis players to achieve high postimpact ball speed. Thus, the objective of the present study is to determine how tennis players change the plantar pressure in each foot when they execute longline forehand and backhand groundstrokes in order to increase postimpact ball speed. Methods: Seventeen healthy nationally ranked female tennis players (mean age: 21.7 ± 7.7 years) participated in this study. The players performed longline forehand and backhand groundstrokes (topspin) at four postimpact ball speed levels, i.e., at 80 km/h, 90 km/h, 100 km/h, and vmax. Plantar pressure was measured in each foot [i.e., dominant (equals the stroke arm) and non-dominant] using flexible instrumented insoles. Results: Irrespective of the stroke technique, the repeated measures ANOVA procedure showed significant ball speed × foot dominance interactions. For the forehand stroke, post hoc analyses revealed significantly increased (dominant foot) and decreased (non-dominant foot) pressure values when the postimpact ball speed increased from 100 km/h to vmax. For the backhand stroke, the post hoc analyses yielded significantly decreased (dominant and non-dominant foot) plantar pressure values when the postimpact ball speed increased from 100 km/h to vmax. There were no further significant differences between the other ball speed levels. Discussion: The significantly varying plantar pressure changes depending on the stroke technique and foot dominance to increase postimpact ball speed suggest that specific physical exercises related to the foot (dominant vs. non-dominant foot) and groundstroke (forehand vs. backhand) seem to be necessary for plantar pressure optimization.

RESUMEN

BACKGROUND: In tennis, previous studies have shown differences in plantar pressure depending on tennis-specific movements (i.e., baseline play, serve & volley play, change of direction), playing surface (e.g., hard, grass, or clay), and serve type (e.g., slice, topspin or flat). However, the influence of stroke direction on plantar pressure in tennis players with diverging skill level is unknown. Thus, the purpose of this study was to determine the effect of stroke direction on plantar pressure in each foot during the forehand and backhand stroke among players of different performance levels. METHODS: Thirty-nine female and male healthy adult tennis players (mean ± SD age: 23.5 ± 6.4 years) representing athletes from three performance levels (recreational, intermediate, advanced) participated in this study. The players performed longline/cross forehand and backhand groundstrokes (topspin) on a clay court while plantar pressure distribution was measured in each foot using flexible instrumented insoles. RESULTS: The three-way ANOVA (performance level × stroke direction × foot dominance) showed (a) no significant differences in plantar pressure data between cross and longline strokes in almost all cases, (b) in part, significantly larger pressure values in advanced compared to intermediate and recreational players, and (c) significantly larger pressure data for the dominant compared to the non-dominant foot in nearly all comparisons. CONCLUSION: Regarding an appropriate plantar pressure distribution, our results suggest that during training of especially recreational and intermediate players attention should be paid to the feet rather than to stroke direction.