Relibility and Interpretation of a Tennis Specific Repeated Sprint Protocol in Elite Athletes

Abstract

Relibility and interpretation of a tennis specific repeated sprint protocol in elite athletes. PURPOSE: A major determinant of tennis success is a players' ability to repeatedly and explosively make position around the playing surface, which can generally be described as their repeated sprint ability. To date, a variety of repeated sprint protocols have been described, yet these do not reflect common time intervals of tennis play nor have the authors adequately described how the test results can be best interpreted. METHODS: Data was collected on the elite national development squad (female n = 7; male n = 6) as part of periodic physical conditioning evaluation. Testing was performed on an indoor running track with 48 h between tests. Strong verbal encouragement was provided to all athletes on each occasion to encourage a maximum effort. Prior to the repeated sprint test, athletes performed 3 maximal 20 m sprints with 2 min rest between efforts to determine a maximal sprint time and for confirmation that the first repeated sprint was at least 95 % of maximum. Following 10 min recovery, the repeated sprint protocol (10 maximal, 20 m sprints every 20 s) was performed. Split times for all testing was recorded at the 5, 10, 15 and 20 m distances. All timing was recorded electronically using wireless infra-red dual beam timing lights and the 20 s interval timing of repeated sprint test was conducted using a stopwatch. The fatigue decrement score (%) was calculated according to the following formula Fatigue Decrement = ((TT - IT) / TT) × 100 Where TT is the total sprint time for the split distance of interest, and IT is the ideal time or the total time that would have been achieved is no fatigue occurred following the first effort. Reliability was examined using the Technical Error of measurement (TE) and Smallest Worthwhile Change (SWC). RESULTS were interpreted for relationships between fatigue scores recorded from different split distances. RESULTS: The repeated sprint protocol TE was shown to range between 0.86–1.94 % for the fatigue decrement score and 0.17–0.34 s for the total sprint time across split distances. A summary of the mean decrement score and total time results for trials 1 and 2 are in shown in Table 1. CONCLUSIONS: We have demonstrated that in this athlete population, using a repeated sprint protocol designed to mimic repeat sprint demands of tennis, that it can be reliable with a range of observed TE similar to or less than the desired SWC. It is questionable whether a 10 m split time provides any deeper understanding of the athletes repeated sprint ability, however measurement of the 5 m split provides insight into how the athlete achieves their 20 m result. A properly administered repeated sprint protocol should enable the sports scientist or strength and conditioning coach to elucidate deficiencies in both an athletes' ability to accelerate and maintain a high linear sprint speed. Practical Applications: It is the authors' opinion that an acceleration (5 m) to speed (20 m) decrement ratio should be as close to 1:1 as possible. The described athletes therefore have a better ability to maintain linear speed and require acceleration training.