Abstract
In brief: The heart rates of 17 male tennis players (aged 18 to 44, mean 31.4 ± 7.3 years) were monitored during singles and doubles competition. The purposes were to compare average heart rate intensities of players during singles and doubles competition, and to document the amount of time spent in continuous activity. In a one-hour singles match, subjects reached an average of 61% of their maximal heart rate reserve (MHRR), whereas in doubles competition they averaged only 33%. The authors concluded that singles competition in tennis meets the MHRR intensity criteria established by the American College of Sports Medicine for developing and maintaining cardiorespiratory fitness. However, doubles competition does not meet those criteria and should not be considered as an exercise regimen for developing fitness.