Shirts Optional?

Up until now I didn't realize that in China you have an option of wearing a shirt at the gym?!?!?!

Okay, I apologize for the picture being so horrible however I was on the treadmill running and was trying to be really discreet about taking a picture.  When I first saw him out of the corner of my eye I did a double take, actually more like a triple take, and it took me a few minutes to process that he didn't have a shirt on so I slowed to a fast walk, picked up the phone pretended to push buttons then turned and snapped a pictures.  Then right back into a run.  I hope no one noticed!  

So anyway in the middle in the blur there is a middle-aged Chinese man with only shorts on!  See I'm actually really doing you a favor with the blurry picture... you can get a glimpse of the fact that it's a guy with his shirt off but you're spared from witnessing the beer gut and hairy chest bits of him!   Yep, no shirt and just going about his business like he was hot stuff.  I didn't know whether to laugh or cry, I mean come on man, seriously we don't want to witness you with your shirt off.  I was baffled to say the least, I've been going to gyms for quite a some time and NEVER EVER can I recall where men (even super fit buff hot dudes) would work out and lift weights without shirts?!?!?!   I know it's hot in the gym but I didn't think it warranted going shirtless.  
But hey this is China, you can do what you want!