I just started doubles last week. A 4 mile every morning in addition to regular training.
I'm just looking for other people's experience with doubles. How long before you noticed significant improvement? How much improvement?
My main goal is a 15.30 5k in June, I'm going to be patient and keep the miles easy most of the time. I plan on reducing the effort of interval workouts by about 5% aswell.
BTW, I'm 16(almost 17) and have been running for about 2 years at 40mpw.