I'd have to ask what is the point of being able to do 100 pushups, that's what it's about right? Why not rather do something that will actually make you strong such as for example deadlifting or russian kettle bells?
You could do 100 pushups, but can you do 20-50 decent pullups? dips? How about 1 arm pullups or squatting with just one leg etc etc...
I'm just curious, only reason why I'm asking.
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out of experience (when I did MA/MMA, years ago) we all did 100 pups in one go. That didn't mean we were strong, just that we could do that alongside 100 of everything else like situps, squat to standup position, etc etc. So far the only really challenging pushups was with either something like one hand or doing them at an angle.
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Furthermore I'd be really careful of doing a 100 or more of X, because a lot of repetition will injure some folks. I don't know, just so many other methods which seems better I know of to get yourself to a point of strength, endurance and fitness.