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JOURNAL
OF
SPORTS SCIENCE &
MEDICINE
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Research
article
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THE INFLUENCE OF BALL VELOCITY AND COURT ILLUMINATION ON REACTION TIME FOR TENNIS VOLLEY |
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Jui-hung Tu, Yaw-feng Lin 
and Shu-chen Chin |
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Department of Physical Education, National Pingtung University of Education, Pingtung, Taiwan |
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© Journal of Sports Science and Medicine (2010) 9, 56 - 61 |
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| ABSTRACT | |||
| The he purpose of this study is to examine the effects of ball
velocity, court illumination, and volley type on the reaction time (RT)
of a tennis athlete for a volley stroke. Eights cases with two different
ball velocities (high and low), two volley types (forehand and backhand
) and two court illumination levels (dark and bright) were studied. The
30 participating subjects consisted of 18 male and 12 female college tennis
athletes (age: 24 ± 3.2 yr), with a United States Tennis Association (USTA)
ranking above 2.5. In order to ensure the validity of real-world correlations,
the experiments were designed to simulate real competition situations. Reaction
times were measured for volley strokes in response to different approaching
ball velocities (high: 25.05 ± 0.37 m/s and low: 17.56 ± 0.92 m·s-1)
for several volley types (forehand and backhand) and court illumination
levels (55649 ± 4292 lux and 363.24 ± 6.53 lux on the court). During the
tests, the signals from an electromyogram sensor and a 3-axis accelerometer
(± 50 g) were recorded using an NI DAQ card (NI PXI-6251) and then analyzed
to determine reaction time (RT), premotor reaction time (PRT), and motor
reaction time (MRT) through the LabVIEW system. Subsequent 3-way ANOVA analysis
indicated no RT, PRT, or MRT interaction between ball velocity, volley type
and illumination. The ball velocity and illumination parameters did affect
RT and PRT values significantly with p < 0.05, no significant variation
in MRT was observed across any implemented experimental conditions. All
experimental results indicate that ball velocity and illumination levels
strongly affect the value of PRT, but have no significant effect on the
value of MRT, the changes in RT were dominated by PRT. Key words: premotor reaction time, motor reaction time, electromyogram, tennis. |
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