Will too much muscle exercise harm the muscle? I am planning to do push-ups challenge, but will I damage my arms if do too much of them?
Since these challenges usually involve high levels of over exertion I would steer clear of it. The last time I heard of the challenge it was 100 push-ups a day for 30, 60, or 90 days. This can definitely take a huge toll on the muscle groups involved, especially if you're not already used to this kind of exertion. It really heavily depends on your current fitness level and where you stand. If you can already easily do 100 push-ups in a single sitting then you're probably not interested in the challenge anyways and should lean more towards chest, arm, and shoulder workouts to get the definition you want. If you're struggling to do 10 push-ups then I would recommend this even less because it can bring in the psychological issues of failure upon repetition and feeling like you're not really getting results.
I would recommend reading "Overtrain if you don't want to gain!" over on the bodybuilding website. They provide a lot of good information on this topic. While you might not be specifically targeting the idea of bulking, overworking a muscle group is hardly ever a good idea. There's a big difference between breaking it down to build it back up and just destroying it. To quote that particular article:
They either do too many sets, work out for too long, or train too many days per week. The result? OVERTRAINING! And with it comes little to no gains in size or strength (and in severe cases, muscle loss, illness, and/or depression).
Focusing too much on a single muscle group can indeed cause issues. As @JohnP stated in a comment, a severe condition is rhabdomyolysis which is a breakdown of muscle tissue that releases a damaging protein into the blood. Feel free to read more about this condition over on WebMD. Another handful of issues that can occur are:
- Trauma or crush injuries.
- Extremes of body temperature.
- Ischemia or death of muscle tissue.
- Low phosphate levels.
- Seizures or muscle tremors.
All of which can indeed lead to the above mentioned condition.
In terms of your challenge, I would take a different approach and do similar exercises working different muscle groups in alternate patterns. This is an approach that a lot of people follow in the fitness industry because it works. For example, I lay out my workout plan for the month a week prior to the month beginning. This might be a typical week:
- Monday: Biceps, Triceps, Forearms, Grip
- Tuesday: Chest and Shoulders
- Wednesday: Core and Cardio
- Thursday: Thighs, Gluts, Calves
- Friday: Back/Speed and Resistance Training
- Saturday: Long Run
You'll notice that each day focuses on a specific topic (or area) and the idea is to do the workout in the order given; for example Monday I would alternate between bicep and tricep workouts and then switch to forearm and grip workouts. Tuesday I alternate between chest and shoulders. By no means would I follow the exact same pattern every week, and definitely not every day.
I hope this helps, and good luck to you in your endeavors!
For a beginner, the accepted answer is probably OK.
But for an advanced strength athlete, high volume can be very effective. For example, Steven Proto (former weighted pull-up world record holder) just completed doing 100 pull-ups every day for 100 days. Shortly after this, he crushed his six-year-old pull-up rep PR of 36 with a set of 40 (at the same bodyweight).