All would be. Think about when you go to gym, your pushups, situps, runs, vsit etc. are always different timings and such from the boys.
If a person really wants to achieve a goal such as this one then a person must be dedicated and determined into reaching this goal. In this case, Isaac should train more and play less. It is not going to hurt Isaac one bit staying off the video games or reducing play time for awhile. Responsibilities come first I always believed in work hard first...play hard later.