getting sick while running

Question
Hi there,

I start dry heaving/gagging after what feels like not much effort has been exerted while running. It happens more towards the end of the run (usually 20 or 30 minutes) or after I run up a hill. I have even thrown up a few times. It is very discouraging because it causes me to not push myself when I know my body can handle more. I can ride my bike 50 miles or swim for an hour and feel fine but for some reason, running does not sit well with me. I am 23, weigh 116, and eat pretty healthy (meals three times a day with light snacking). I drink approx 2 to 3 pints of water a day. I also drink a cup of coffee or tea in the morning. I wait at least three hours after eating before running, unless I run first thing in the morning and then I don't eat. I am not a smoker. I hope I answered any of your possible questions. Please let me know if you have any advice.

Thank you,

Randi

Answer
Randi,

This is a weird problem. The only thing I can think of is that it has something to do with the way your body reacts to lactic acid buildup. I would strongly recommend seeing a doctor (preferably one with a running background). You may also try asking the other expert on this site, John DeHart. He is a good friend of mine and he may know.