Family and life pressures are prob. one of the biggest reasons that the younger masters runners (early 40's) often dominate the local races. Having the time to train is so important. Runners in their late 20's and 30's just don't have the time to establish careers and families at the same time.
Fortunately for me I train mid-morning from work for the main workout with a training partner every day during the week. Then a short run after work during the week. Longer workouts and races on the weekends. When I have to I run at 6:30 in the morning if I won't be able to get out of work for a while. I run my own business which is helpful.