Do interval training
Do high-intensity interval training
Do tempo runs or threshold workouts
Add hill sprints or incline intervals
Increase weekly aerobic volume
Train at or near VO2 max pace
Use progressive overload
Include one long endurance session each week
Cross-train with cycling, rowing, or swimming
Improve running economy with drills and form work
Strength train regularly
Maintain consistency over months
Recover adequately between hard sessions
Sleep enough
Eat enough carbohydrates for hard training
Stay hydrated
Monitor heart rate and training zones
Reduce excess body fat if appropriate
Avoid overtraining
Re-test and adjust training plan regularly