Most of the siblings who go to the gym may have a goal of body harmony, but the motive is mainly to get a six pack body. To take that picture and show off the beauty of the body. This isn't cardio. This is not for health. It's for the muscles. If you are more obsessed with getting a beautiful body so that when you wear tight t-shirts it will show the beauty of your body, then your troubles have started.
You become very fixated on muscles and you think it will boost your self-esteem. Muscles don't give you courage, or increase self-esteem. It will only feed your ego, and your Ghurur will engulf the sky.
Girls who praise you for your muscles will not be the same girls who will accompany you to continue to a higher level of marriage and being life partners. He's there to ride, and that's all.