I (32M) sometimes get lightheaded after working out. Usually it’s after a light cardio warmup and some weight lifting either at the machines, or free weights. I’ll start out fine, then after the third or fourth workout or so my head starts hurting and I get a little dizzy. For context, my diet consists of high protein, tons of water (shoot for a gallon a day), and I almost never work out on an empty stomach. I get roughly six hours of sleep a night, and I don’t consume very much alcohol (although I do smoke weed more often, about 3-4 times a week). I figured the weed might have something to do with it, but my girlfriend smokes even more than me and she’s in the gym 4-5 times a week with no problem (or at least not this one). Does anyone have any thoughts as to what might be causing this? I know it can’t be dehydration, as I said earlier I drink plenty of water, and eat and drink a lot of protein.