The American T'ai Chi Associates recommends looking for a school that adheres to the original principles of the martial art it offers, rather than one that dilutes them by, say, pairing jujitsu with kickboxing: The purer the teaching, the more your child stands to gain.
The mean calories burned per minute of tennis, based on the list of 5 activities, shown below, for an average male, weighing 190 pounds (86 kg) is 9 Calories per minute. The average per minute for an average female, weighing 163 pounds (74 kg) is 7 Calories per minute.
The Harvard Heart Letter also took its estimates out on the street, so to speak. Using the same three hypothetical test subjects, bicycling at a leisurely 12 to 13.9 miles per hour burned 480 calories, 596 calories and 710 calories per hour, respectively. Increasing the pace to the range of 16 to 19 miles per hour rated a burn of 720 calories, 892 calories and 1,066 calories, respectively.