Today I went to work out in the fitness room and it was locked So I had to exercise outside. I live in Arizona and it was about 90 degrees this morning. I didn't do much because it was so hot, I just powerwalked for about 30 minutes. So my question is, do you actually work harder and burn more calories when it's hot or does it just feel that way?

I'm betting that you lose more water weight (fluid loss), but you don't burn more calories in the heat. Just a guess, though!

Yes, you pretty much drop more water--better be careful about dehydration risks in such cases, because at times we may feel like "we can do it", and then, bam, come the nasty side-effects.

yeah I carried a water bottle with me.

thanks!

Yep, seconding and thirding the others. I have a hard time working out in the heat, so when a fitness room is closed, I try to find things I can do around the house to increase my activity.