Want to Run Faster? You Probably Don’t Need More Speedwork.
Aerobic capacity, not speed, is usually the limiting factor in how fast you can race, even for a distance as short as the 5K.
aerobic endurance
Can I Run Low Miles and Still Succeed in the Marathon?
You can run a good marathon off a low-volume, high-intensity training program, but to reach your full potential, you have to have it all: volume and intensity.
Four Approaches To Cross-Training For Runners
Should you be a maximalist, supplemental, seasonal, or emergency cross-trainer?