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One important concept is time under tension when we discuss resistance training. The 100 push-ups challenge here is a great idea, but participants should not to it with speed to get over with it. There should still be body control or otherwise joints and tendons and cartilage have to bear more workload than they should. That's why reducing the number of push-ups when that leads to a better feeling and better body control is never wrong. Everyone of us knows this one guy from the gym hammering out the exercises as if it was about speed and not about strength, body control and body tension. This is problematic even more push-ups with one's own bodyweight as everything that creates force from exaggerated acceleration will make the body sore. So there is an important line between pumping out a high number of push-ups while neglecting form and doing it mindfully with the goal to make it for health reasons while not losing sight of the goal of this challenge.
I purposefully focused on quantity over quality since it had been a decently long time that I had been neglecting strength and/or resistance training, and so in that regard, felt a bit of a purpose to pump out various quantities of pushups while my body was getting used to it, so I probably did not begin to adjust my approach until after I had reached 200 pushups per day.. so that was on my day 95.. and then after that I tried to stick with 200 per day, and now I am graduating to the next level of doing even fewer pushups and perhaps still getting a decent amount of exhaustion from the pushups while not giving up on the idea of doing pushups every day, too.
Yes I am just bringing up some concepts that I know have been proven with research, but above all well researched concepts in terms of physiological parameters is psychology and motivation. I brought this up when it comes to food, same thing. It's worthless when someone tells you what the best diet is when in fact you realize that you can't maintain it. The best diet is the one that is as healthy as possible and that you can maintain for as long as possible.
It is the exact same thing with exercise. Time under tension is indeed an important concept as the muscle is a bit similar to an onion and with increased time under tension you send impulses to all the various layers/fibers of your muscle. The goal in a best case scenario is of course to stimulate them all. Some people take it to an extreme and have their repetitions take 7-8 seconds, but I can tell you that I could never maintain that for long as it would drain me psychologically. I would lose interest in doing the exercise. I think we both are more the average guys here who love to get some numbers done as well. To achieve some numerical goal.
However, I do pay attention to soreness. Pumping out push-ups or any repetitions of any exercise for that matter should not be too much of a burden for the joints too often. Joints can recover and adapt and that's a desired outcome though.
But once you achieved the goal of reaching a certain number of push-ups, I think it can be fun to torture the body a bit at times with time under tension techniques as well. A little bit of soreness in the muscle and not in the joints doesn't feel too bad sometimes. Feels somewhat good because you know you have performed.
But as a conclusion, being able to maintain an activity is first priority. May that be for fun or dedication or discipline. 200 a day is enough stimulus to strengthen the muscle. It won't grow a lot, but it gives healthy muscles that understand they are needed and hence, here to stay.
Are you also into cardio at the moment?