When I was working out today I felt like I had no energy to do anything. I was on the treadmill and I usually feel full of energy and do it about 60-80 minutes without any problems. Today, I was getting tired too quickly and had to slow down a lot. However I did complete 60 minutes but I didn't burn as much as calories I used to burn.

I had ate good and I don't feel sick.
I wonder what was wrong? Should I drink something before I start working out?

Dehydration can certainly zap your energy so that might be a piece of the puzzle. Where are you in your cycle? I notice a change in energy level some months with that. Could just be an off day...how's your stress level? I wouldn't worry too much unless it keeps up. Maybe try to get a little extra sleep the next couple of days.

Peg

Workouts vary. I wouldn't change things based on one occurrence unless there was an obvious reason.

The chocolate cravings is here. I assume I'm close to TOM.

If you aren't eating enough protein, or enough calories overall, that can also make you tired during a workout.

A snack containing protein 30 minutes before a workout can help, but you should also look at your daily intake.

Jay

I think it is pretty normal to have an off workout now and then, I know I do.