CARBOHYDRATE SUPPLEMENTATION IMPROVES STROKE PERFORMANCE IN TENNIS

The effect of carbohydrate supplementation on stroke quality during pr olonged simulated tennis match-play was investigated. Well-trained ten nis players reported to the test center three times. At each occasion they performed a pretest, consisting of the Leuven Tennis Performance Test (LTPT) and a shuttle run (SHR), which they repeated (posttest) af ter a 2-h strenuous training session. Throughout the test session, the y received in a double blind random order either a placebo drink (P), a carbohydrate solution (0.7 g . kg(-1) BW . h(-1); CHO), or CHO plus a dose of caffeine (5 mg per kg BW). Stroke quality was evaluated duri ng the LTPT by means of measurements of error rate, ball velocity, pre cision of ball placement, and a velocity-precision (VP) and a velocity -precision-error (VPE) index. Pretest scores were similar during P and CHO. During P, compared with the pretest, stroke quality during the p osttest deteriorated (P < 0.05) both for the first service and strokes during defensive rallies and for SHR performance. However, compared w ith PI the increase in error rate and number of nonreached balls in de fensive rallies was smaller (P < 0.05) during CHO. Similarly, CHO atte nuated (P < 0.05) the increase in error rate and the decrease in both the VP (P < 0.1) and VPE (P < 0.05) indices for the first service upon fatigue. Furthermore, CHO improved posttest SHR performance. Stroke q uality and SHR time were similar during CRO alone and during combined CHO plus caffeine administration, both for the pretest and for the pos ttest. It is concluded that CHO supplementation improves stroke qualit y during the final stages of prolonged tennis play. The data prove tha t CHO intake may facilitate the maintenance of physical skill quality during long-lasting intermittant exercise to fatigue.