Blood preasure I would guess.

Maybe you are not breathing properly or your blood pressure has risen. Have your pressure checked as a standing pressure and then after running just to make sure Make you you are breathing properly.

you should breathe when you run...don't hold you breath and drink some water.

See a cardiologist pronto for a work up to make sure its not your heart.

I just had my 14 year old at the doctor because he has been getting "lightheaded" especially with exercise. The doctor advised that he is not getting enough fluids and also suggested drinking a drink like gatorade because it replenishes your electrolytes quicker. Just some FYI for you.

Hypoglycemic?? Or lack of iron??

Well it depends on how far you run. When you really exert yourself and run, I don't know, 3,4, maybe 5 miles or more, your blood vessels get dialated, so if you slow down too fast the size of the blood vessels changes the comprehensive blood flow to your entire body, causing a "lightheaded" or "slightly dizzy feeling". If you lay down head even with your heart, the blood will pump to your brain and the feeling should go away rather quickly. I wouldn't worry to much about it unles yhou are feeling dizzy during the run when your heart is really pumping. It is normal to feel dizzy immediately after you have worked hard. I have had to take breaks from my regular workout cycle, and when i come back I am always dizzy after the lifts for about a week or two. But once my body gets back in the swing of things I notice it pretty much goes away. Today I ran 5 miles, and felt dizzy afterwards. Don't let it bother you too much. Like I said unless you feel somethings not right during the run, you are most likely fine! Make sure you are eating healthy and getting enough fluids as well! Have a good one!!

i get dizzy... but thats cuz i dont drink enough water

Perhaps you're dehydrated? That's whats wrong with me when I feel dizzy after I run.

Dehydration would be the best bet, although a lack of rest can cause headaches/lightheaded as well.

Best advice, see your family doctor.

My husband was a drill instuctor and borrowing that there is no underline health condition, you should make sure you do the following. 1. Stretch before running. You need your muscles to warm up and get the blood flowing. 2. Do deep breathing exercises before your run. Your lungs are going to work hard during the run and this will help prepare them. Most people are shallow breathers 3. Pace yourself 4. Make sure you are well hydrated before the run 5. You can overheat your body in 80 plus weather so try to run in the morning when its coolest 6. If your a smoker, do not smoke before a run 7. Make sure you are breathing in and out of your nose and not your mouth. This will help regulate the amount you actually are breathing in and expelling. A nice steady breath will allow the oxygen more time in your lungs. If you breath too fast you will exhale the oxegen needed for your lungs. 8. For a good long distance run or for someone not use to running it will take some time to adjust. Remember that your blood is pumping through your body at a faster rate and the cells in your brain have to absorb as much oxygen as possible. 9. Don't dead stop when your done. Walk for at least another 5 minutes this will also help clear your head. I don't know why but it works but I suppose maybe its because you will still be breathing heavier without slowing down the blood flow too much giving the brain time to adjust.