Do exercises where you are sitting down ex: rowing machine. I also do bicep curls and most weight exercises when sitting on a bench. I’m unsure how effective it is, but it definitely is better than getting dizzy. I know that swimming can be good as well, but I haven’t tried it. Also, try to take breaks, drink some water with electrolytes or have a small snack! Start small and work your way up to longer gym sessions or more intense workouts.

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