Basically, there are two types of gym goers, the ones who just can't do work out without air conditioning and the others are who tell you that you get better results without ACs. Well, I have read a lot about this and even asked celebrity trainers and here I want to stay this, "What matters the most is that you really get up and go out to work out. AC or no AC does not really make a difference."
When it comes to the impact of an AC on your body, the myths of negative effects on your body are endless and often exaggerated. People think that one should work out without an AC to get better and faster results. The other very common myth that you hear is the more you sweat, the more calories you burn.
However, the temperature can impact on one's body during the work out, but what matters the most is inhaling fresh air while you work out. So all you need to chill when it comes to air conditioning in your gym. What you need to ensure that you give your 100 percent during the work out time and make sure the air you breathe is not stale.
There is one option though. You can go at that part of the day when there is no one or hardly one or two person in the gym. Then you can get the AC turned off.