if u keep getting bigger and bigger, you coud get very unhealthy, so wut you should do, and wut i do, is eat just as much as normal, but eat healthier stuff. then, try cutting back on how much you eat when you get that downed. running is very good. being active is very good, and that will help you be fisically fit, but the reason y u just keep gaining is you probably eat too much unhelthy. just runninng around wont help all of it. it will get u fisically fit, but not skinnier. GOOD LUCK!