Run 800 meters stomach ache problem ... ...

girls sometimes finish the 800 meters is a stomach ache,

note that the pain is not a stitch, not stitch is sore ... ...

and especially severe pain, tugging pain ... ... and not the days of each month

sometimes, too.

I ask why? How can they be avoided?

Also ran 800 Yousha skills = = ... ...

Thanks!

less to do