I think the first time that I saw "Muscle" in real life was when as a school, we'd go to the local Leisure Centre. (Swimming pool, gym, badminton squash...) you know the usual.
We'd been playing badminton and had gone back to the changing rooms, these were an open sort.
No cubicles. Just benches and guys of different shapes and sizes changing in to and out of their clothing, trunks and shorts.
The guy that stood out. Was near to me. Talker than me. But boy did his body look wonderful to my 13 year old naive self. I should think he was in his mid twenties. Tanned. Tight firm muscles, veins covering his not huge muscles. He'd obviously had just worked out. But, boy that sight remained in my minds eye for a long time after. If almost felt as though he knew I was watching him too. He'd dressed slowly and every now and then he'd give a little flex of his pumped body.
Although it was over thirty years ago. It still makes me smile and wonder off in to that memory of innocent youth.