I would add more variety, I think you would have done that in the future anyway. Push ups are awesome, but they also get old.
Your off days are when you're doing ice hockey/basketball or are they totally off? do you need the time for other stuff? cus while rest is important, you're probably not exerting yourself enough to need a day of total rest. Only if you're sore should you take a full day's rest (assuming you have the time for a workout, that is)
It sounds like you're trying to do full-body stuff when you do work out, which is good. I would structure it like this:
Monday: push ups, pull ups, squats (working up to single leg variations)
tuesday: off (or sports)
wednesday: uphill sprints - slowly work yourself up to 10 dashes, it's okay if on your first few outings you don't even get to 5. Do one hard uphill sprint, rest 2-3 minutes and try again. WARM UP THOROUGHLY before starting, do 50 jumping jacks or high knees or anything like that, and a short run as well. Don't neglect sprints, they're great for fat loss.
thursday: off (you will definitely be sore after sprints)
Friday: repeat monday (or sports)
Saturday: repeat monday (or sports) or off
Sunday: depending on previous day, repeat monday or sports, or off.
Consider also playing with tempo, meaning don't always do your push-ups at the same speed, sometimes go faster, sometimes go slower - do pyramids (1 push up, rest, 2 push ups, rest, etc up to 5 then back down to 1) for all exercises not just push ups.
Learn and begin to practice static holds, such as the plank (relatively easy) to the L-sit (may need push-up handles for this one) read about the planche and the front lever, two really advanced bodyweight holds but that both have progressions that are easier to start on and provide a fun challenge. If you find you're into these, your whole routine might change to give both of these more of your time. Maybe venture into learning how to do a handstand which will require strengthening your shoulders, etc... honestly the world of bodyweight training is very diverse.
Think about investing on a weight vest (though start with a bookbag and some books if money is an issue) for added resistance, think about building a sandbag for a cheap yet awesome tool, make or buy gymnastic rings to attach to your door-frame pull up bar (one of the best tools for upper body development) and of course, take your workout outdoors from time to time! pull ups from a tree branch, lift some rocks, have fun!
Lastly, visit these really helpful sites full of tutorials and ideas for minimalist training: Al Kavadlo – We're Working Out! | We're Working Out!
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