Yes, I am always amazed that we don't have a siesta, or a down time, during the heat of say, February. In Australia we just soldier on and wear it like a badge of honour. I think it is a sign of stupidity. I don't believe we work in partnership with the weather here. Think it goes back to convict days.
I spent my first christmas in Queensland Gold Coast visiting our daughter. I had great plans with all the things to see and do. What did we achieve? A big fat zero !! I have never experienced such humidity, it was completely exhausting.
If it is hot and humid, I definitely feel drained, so try to stay inside and drink lots of water. If we are having a long stretch of hot days is when I feel it most. Emergency services tend to warn us to stay inside and check with our neighbours on days of extreme heat. I have had heat stroke before, and it is not very nice.