In tennis, service requires a variety of complicated movements. Given the importance of taking the initiative to obtain points in a tennis match, it is crucial to make full use of speed and spin rate of service. Generally, a service that requires a higher spin rate would slow down, and a service that has increased speed would have a decreased spin rate. For players who are disadvantaged in height, although controlling spin rate is essential, slowing down service speed should be avoided. For these players, the challenge of service is to improve the speed without decreasing the spin rate. Players must also be trained to build physical strength required for this skill. It is not uncommon to work on physical training without a racket; however, few studies have reported on the effects of cultivated physical strength on on-court tennis performance. Therefore, this study aimed to propose physical measurements that could be used as indices to improve service performance in 58 elite Japanese junior male players. To test service performance, we used TrackMan tennis radar device to assess speed, spin rate, impact height, and impact depth. To test physical strength, we measured 5- and 20-m sprint, broad jump, medicine ball throw (forward, backward). We used a significant multiple regression equation to predict the first service speed obtained from the broad jump and the Medicine ball throw (backward). Additionally, a strong correlation was obtained between the predicted and measured values. In addition to physical strength, we suggest that the depth of the impact point (taking the hitting point forward toward the net) is important for improving the first service speed. However, we were not able to identify the physical strength test items that improve service spin rate. Other item should be examined in the future to determine the physical strength associated with spin rate. This result could help connect physical training and service performance.

The purpose of this study was to investigate the relationships between the normative performance proˆles proposed by O'Donoghue (2005) and the winning of sets in actual women's singles matches of professional tennis. Twenty-four matches from 2010 and 2011 US Open tournaments were analyzed with 13 performance indicators. The normative performance percentiles were calculated and the total sums of percentile values were compared between winners and losers. As a result, the normative performance percentiles are obtained from actual match data. The normative performance percentiles in current study show similar tendencies compared with O'Donoghue's (2005) data. The normative performance proˆles in each match show diŠerence of performance between winners and losers of sets visually. The diŠerence of the total sum of percentile values between winner and loser signiˆcantly depends on types of set scores. That is, large diŠerence in set scores show large diŠerence of the total sum of percentile values. It suggests that the total sum of percentile values have large diŠerence between winners and losers, resulting in an overwhelming victory. It is concluded that the diŠerence of the total sum of percentile values have positive correlation with diŠerence of set scores between winners and losers.