Why do I return with dizzy and see black when I run or hurry?

the other day within my aerobics class I was running 11 lap in the gym (with the other girls) and I get super dizzy,really weak and started seeing black. It be really weird/scary.
It has happen a quite a few times within the last few weeks during or after class.
I also am contained by karate and have equal problem when we do jumping jacks,little jump and running in place.
I've never have this problem before.Why do I return with dizzy and see black when I run or hurry?
Dehydration is the discernible first choice, but i assume you've investigated that one. Sometimes it might be a circulatory problem or a low blood pressure issue. Your diet may have changed and you're not getting adequate protein? or maybe you're not getting adequate carbs. I am not sure.
dehydration? Try to drink ALOT of water. And get sure you eat something small as resourcefully.
If that isn't it go to the doctor ASAP
resourcefully i have anorexia and bulimia and i do alike thing u might want to budge to ur docter and get checked to see if u enjoy any of these problems,or u could just be working ur self to concrete,but i would get a professional view,good luck<<<<<3
You may be desiccated. Do you drink plenty of water since, during and after your workouts.
It could be from not eating satisfactory or getting enough fluids and rest past you exercise,or not warming up in good health enough past you start, being tired to start near or sick, new medication, recent weight loss or your blood pressure is for a time low. Eating healthier, getting plenty of rest and fluids should resolve the problem, save see a dr about it.
engineer sure you eat and enjoy something to drink before you do these classes.
its any a fall contained by blood suger or dehydration.