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I read a study that showed you begin losing muscle mass at 40. As I approached 40 a few years ago I made it a point to not let this happen and started doing pull-ups daily along with curls, bench press, sit-ups, climbing stairs, and taking long walks. So I've been at it for a couple years already, but when I saw the opportunity to get involved in this 100 push-ups per day thing, I decided why not add this into my routine and really push it. Given that I've been on a muscle building journey for several years, this was probably an easier move to make for me than others, but everyone needs to start somewhere. That's why I recommended people do the amount of push-ups that the BTC price is. 43 a day should be doable for most people and they can work their way to 100 with the Bitcoin price. I'm surprised how much of an effect 100 push-ups a day has had on me already. I've done
440 460 (had to bang out 20 while writing this) push-ups now counting this morning and that will be 500 by the end of the day. I'm also still maintaining my other workouts, and have added squats to my routine. I am going to start adding my bench press sets in with my push-ups in an attempt to be able to maintain this longer term, but urge everyone to do something. Lets all get ripped and rich together. Even if you start by walking 100 steps, or doing 100 jumping jacks... Whatever you need to get you started on your journey. Health and wealth baby!
These ideas (and list of various actions) are inspiring including some of the various kinds of resistance training, and yeah sometimes we have to figure out how to fit these into our schedule.
I am also thinking that there may well NOT be a need for high level weights.. but just moderate level of weights.. including some of the exercises that can be body weight only.. and sure no one is saying to completely get rid of cardio.. so walking and other kinds of cardio can be good in moderation, but cardio in itself does not build or maintain muscle mass - especially as we get older, whether that is in our 40s, 50s, 60s or beyond.... and so maybe we cannot even expect to be completely buff at the various ages as we are likely losing some muscle mass. .because there likely are some genetic components, but there are also plenty of studies that involve showing problem of sedentariness.
Wait...wait a sec....you can take breaks?

Whatever it takes... As an old hustler used to mutter to me often in the 90s, "There's no rules to this shit."
Even though Greyhats seemed to be referring to NOT having to do all 100 pushups at the same time, I also agree that in regards to various other kinds of exercise, there are not any exact rules.
It seems to me that there are probably some kinds of exercises that are better than others, including being able to do it fairly regularly (whether daily or a few times a week) and certain kinds of variations in the kinds of exercises that would include some of the categories of cardio, flexibility and strength... but this pushup challenge is supposed to be daily.. so personally I am willing to try it for a while.. and I was likely exaggerating when I said that I would continue to do them until $100k, even though I am keeping track to see how it goes and if I might get better at it (and it becomes easier without causing other possible issues).