all track runners and xcountry runners have very slim bodies and weigh under average but more power to them . i can run a mile in like 7:35 or something.. I used to run before i realized with my fast metabolism and my running habit im not making any good weight gains in weight lifting. So i only do cardio once a week and i work out 5 days a week. I bench 250 max on a really good day. I squat 320( i gotzz chicken legs), and i can curl 110 lbs( barbell) comfortably for 3-4 reps. But my reular routine is nothing close to this, I only check my max to see my progress. believe it or not lol. but i have been working out for 4 years+.