It’s important to occasionally conduct a complete assessment of your training program to determine areas of challenge and opportunity. Runners, by nature, are task-oriented and can focus almost exclusively on completing daily workouts.
Determine where you need to improve (i.e., nutrition, strength training, post-run recovery, flexibility, etc.) and devote more time and effort into those areas.
There are greater benefits to reducing the duration of a run back and conducting dynamic movements prior to a run to prepare your body for the rigors of running. At the very least, complete your first mile of every run 60-90 seconds slower than you expect to average for the remaining miles. This allows your body to ‘gradually’ warm up and to establish a rhythm of efficiency through a higher cadence and relaxed and rhythmic breathing. Start too fast and you go anaerobic and never find a comfortable rhythm.
Most runners start fast and finish slow. Reverse that trend and you’ll improve your fitness and reduce the chance of an injury.
The Marathon Solution 