yo man i jus read ur thread where u said u want a six pack and how to do it. not to sound like a total douchbag, but i have been the owner of an eight pack since i was 15 and i know a ****load about core training. since u r 13 u shouldnt over do it too much cuz u got a lot of growin up to do. remember the most important part of getting ur abs is dieting, to have a eight pack (six in ur case) u need to be relatively low % body fat i got a eight pack now and im at 4.7% when i carry a six pack (like when im bulkin up or sumthin) i usually have 6-8% body fat. pick good natural foods and dont eat any junk foods or anything thats processed but still get enough calories to keep u goin cuz ur still real young. u already run and stuff so ur good with that. as for a routine i recommend doin this:
weighted situps - 100 total
Crunches - 100 total
Ab wheel rolls (its a wheel with handles and ur on ur knees and extedn out on the wheel and come back to starting position, using ur abs to go down and come back up) - 50 total....(a more advanced way is to do it from ur feet, thats wut i do, but that might be too hard for u cuz its a really difficult motion)
Reverse crunches - 50 total
Oblique crunches - 200 each side
Twists - get a broomstick or sumthin and jus hold it on ur shoulders with ur hands and twist to ur knees, twist the left side of ur body to ur right knee and vice versa. this is done from standing - 200 total (100 each side)
try and do this routine after ur weightlifting has been done and before ur cardio, start off with 3 days of doing this and then once ur body adapts to the load (u'll know when it does) u can move up to 4 or 5 days a week. i work my abs 7 days a week cuz my body is used to the strain so i never overtrain. give it a try for a few weeks man u'll see a difference. good luck!