[Cd00d]

I'm the same - it's very easy for me to ramp up miles and pace in endurance sports, but I've never been able to do a pull up.

I do notice I weigh 25-30 pounds less than my friends that are same height and waist size. I'm 6'3" and when fit hover a little under 170 lbs, while everyone else is 190-200. I think it's a distinct lack of muscle.