Remove the routine

A colleague of mine posed the question: "If you do 50 push ups spread throughout the day, every day, is it as good as 100 push ups done at once every other day?"

To which I responded:

Neither. What's needed are diverse sets of fully functional movements performed at high intensity.

Not happy with my answer, he asked me to elaborate, so I did:

I stand by my answer--and I'm quite aware that you're doing other movements. If your goal is to be as physically fit as possible (which I believe it is), you need to mix up your workouts and focus on your proficiency across all modal domains (skills and drills) and time domains (which means being on the clock). If you're doing a high number of push-ups every day (or every other day), you're (1) clearly not introducing other integral movements into your workouts and (2) you're not giving yourself enough recovery time for that particular movement.

I don't believe that either option you've presented is particularly beneficial over the long haul. It sounds far too routine-ish to me. I would definitely have you keep 100 push-ups as part of your workout regimen, but you need to introduce it at fairly random intervals and intermixed with other movements. As well, you should introduce a different quantity of push-ups in the workouts (20, 40, 60, whatever) and intermixed with other functional movements.

As for spreading the same movement across the day, I don't think that's a good idea. Again, high intensity movements over short time domains should be your focus (it will improve your stamina, endurance, and cardio). If you want to do two intense workouts over the course of each day, that's fine--just spread them out by about 5-6 hours.

Consequently, if I'm forced to answer your question, I would say that you should do 100 push-ups in the same session. I'm sure you could do it. Give it a try. Even if it takes you an hour. Just break down each set into manageable portions and/or intermix it with other movements.