.
Some researchers have criticised the theory, as there is no evidence to support the argument that energy constantly builds up and needs to be used up through play. Rather it has been found that people who are more active appear to generate more energy than those who are less active.
On the other hand, Miller (1968) argued that if play were simply a product of surplus energy, it then means that they would not be able to continue playing when exhausted. As children tend to tire themselves out completely during play. .
A third criticism of the surplus energy is that an animal or child is relaxed and, less watchful and therefore vulnerable to any unexpected danger it might encounter during play. So using up surplus energy is not likely to provide a child with an evolutionary advantage. .
The other criticism of the surplus energy is the one sited by Hayes (2000) as being circular, in terms of whether energy is considered to be surplus or not. .
Relaxation theory - Patrick (1916) argued that play is a recreational activity which allows both children and adult to replace lost energy. He argued that human being cannot cope with the demands on life by modern way of leaving, that it need to get relief by reverting back to the kinds of activities which is used to in the evolutionary past. This he argued could be seen in the way children preferred basic archaic musical instruments like rattles, drums and enjoy playing with animal like toys. .
The first criticism of this theory is that it does explain why people who are not in modern types of occupation also engage in recreational activities. Nor does it explain why children often spend a great deal of time on high-technology activities like computer games, which cannot be seen as a regression to a primeval past. .
Secondly, Ellis (1973) argued that children, who do not engage on modern high-tech work, play more than adults. Therefore, play could not be seen as the way of recuperating from work.