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.
According to a 2012 publication from the Centers for Disease Control and Prevention (CDC), the average American man weighs 195.5 pounds. In two hours of doubles tennis, the average man will burn 712 calories. Typically, women are smaller than men with the average American woman weighing 166.2 pounds according to the CDC. This means that the average woman will burn just 604 calories playing doubles tennis for the same length of time.