Jogging Always Ends in a Stitch: Help? [Forum]

i started trying to lose weight when i was 20, 91kgs and 172cm. I lost 20 kilos in 6 months but for the past 6 months haven't been able to lose anymore weight

so now im 21 and 71kg but i want to go back to a size 8. im still doing everything the same, same gym routine, still eating healthy in the past few months i've even stopped drinking alcohol to see if it helps...it hasn't

a typical day consists of around 1000-1500 calories and 2 hours at the gym

but also i can't jog or run and i don't know why, theres nothing physically wrong with me but every time i try i end up with a stitch, i stretch before hand, and have tried not eating and eating a small meal before the gym

please help!