See how you practice. Being a fitness instructor won't do harm to your body, but your own training may do harm to your body, because first of all, being a fitness instructor definitely needs a perfect figure as a facade, so when you train yourself, you will do harm to your body if your movements are not in place or you don't use the equipment correctly and you don't grasp your strength. This is why some people hurt their knees when running, and their wrists when lifting iron.

Secondly, fitness coaching is also a highly professional job, which requires professional knowledge. As a qualified fitness instructor, you need to learn a lot of professional knowledge, such as sports anatomy, sports physiology, sports nutrition, sports rehabilitation and so on!

Therefore, if you want to be a fitness instructor, you need systematic training. Correct training is beneficial and harmless to being a fitness instructor. If you train blindly, you may do harm to your body. Other questions, you can nod my head.