A prefix is a series of letters, or a word, that is added to the  beginning of a word and changes the meaning. For example, in the  word midnight, mid is the prefix.
The more vigorous an activity, however, the more calories youâll burn. Changes in body weight are related to both the duration and intensity of play. Playing singles tennis at average intensity expends 300-600 kcal/h, while high intensity tennis training expends 450-900 kcal/h. Diabetes. The incidence of diabetes worldwide of persons aged 20 or above in 1995 was 4% (approx. 135 million), a figure that will increase to approx. 5.4% (300 million people) by 2025.
Calories Burned Per Hour. A vigorous game of singles tennis can expect to burn between 528 and 872 calories, depending on your body weight, according to MayoClinic.com. This is comparable to an hour of solid running at 5 miles per hour, or an intense game of basketball. The more you weigh, the more calories you can expect to burn with each hour-long session. Other factors that can affect calorie loss are the size of the tennis court and the type of match you are playing.