1. Do 300's instead of 400's. The monotony of the one lap workout (400 meters) can become mundane after a while. Switch up your 400 meter repeats by doing 300 meter repeats. What's good about the 300's is that the splits will be quicker and shorter, but still have the same anaerobic affect without the longer distance attached to it. Also, 300 meter repeats are not specific to a certain type of athlete. So this type of workout is good for someone who is running a 5k or for someone who is running a marathon.
Try: 7 X 300 with a 60 second break in between each interval
2. Start doing plyometrics. Plyometrics improve overall strength by recruiting on the same muscle fibers that the running motion does, but without the long wear and tear of a run. Plyometrics are geared at improving your overall running economy because they create greater power by training the muscles to contract more quickly and efficiently.
According to competitor.com, "One of the most important functions of muscles and tendons in running is to store energy. Like a pogo stick, your body can store energy from impact and then release it to propel your body forward. As such, a large portion of your propulsive energy actually comes from the energy stored in your legs from impact previously made with the ground. This is why you can leap higher and longer if you do a “countermovement” before jumping, like swiftly bending your knees, which allows you to reach much higher into the air than slowly bending your knees.
3. Do 2 hard workouts (metabolic conditioning or strength training, not so much running), the week of the race and take the day off before the race. Yes, I understand tapering is good, and you should still taper, but don't become stale. This will help you to avoid exhausting earlier during the race since your pain tolerance is in recent muscle memory. Try and mimic race motion and pace with you sets and make sure you incorporate some triple extension lifting (i.e. deadlifts, or anything you can pull from the ground).
4. Start using music that matches your cadence. Cadence is the number of steps your take per minute. The more steps you take per minute the less time you spend on the ground, which in turn alleviates the impact on your shins and knees. Advanced runners have a cadence of 180 or higher, however, most runners have a cadence of 150-170 steps per minute.
Matching your music to your run is imperative if you want to maintain a consistent pace. The idea is to forget you are running. You want to transcend mentally and physically in order to be in complete sync with your body and stride.
5. Know the difference between anaerobic and aerobic running. According to Runners Connect, "If you begin to run too hard in the middle of a workout or the start of a race, your body goes into an anaerobic state, producing lactate. If you “go anaerobic” early in a race, you will fatigue sooner, and your ability to maintain pace will take a nosedive. Lactate pools in your muscles, and you will have to slow dramatically to get your body back into an aerobic state. Your PR is out the window and you will be struggling before the halfway mark of your race.
PACE PACE PACE.