Since Adrian was dragged away, he decided that he needed a break from playing. He also needed to exercise in the real world to make sure that he is rehabilitating properly. He has been able to take a few steps without the aid of the exoskeleton which is why he is excited.
What he is not excited for is the excited look that her mother has when she noticed his progress. She even dared to say that Adrian is ready for slight practice even with the aid of the exoskeleton. It took quite a bit of begging and looking at his father to make sure that his mother does not think like that for a while.
He might pull all the muscles in his body if he does the slight exercise that his mother is saying. He could feel getting a bit of weight though since he does not move as much as before. If his mother did not control his diet, then he would probably be putting on quite a few pounds.