One of the keys to successful racing is variable speed training. There are five primary types of running workouts:
1. Basic Speed: Short, fast speed work to improve leg turnover, running form, and explosiveness
*8 x 100 meter strides worked into the middle of a regular training run
*12 x 200 meters on the track. Sprint 200 meters, jog 200 meters to recover. Rinse and repeat.
*Hill sprint repeats. Find a suitably long hill (roughly 50 to 200 meters). Sprint up hill, jog down to recover. Repeat 6 to 8 times. Focus on lifting knees high, pushing hard off your feet, and driving your arms. I usually work this into the middle or end of a regular training run.
2. VO2 Max: Longer repetitions of 2 to 6 minutes run at 3k to 5k race pace, which improve your body's ability to utilize oxygen efficiently
The intervals should be run at your 3k to 5k race pace. Sometimes I aim for my 5k goal pace in these workouts. Otherwise, if you always do them at your exact current 5k pace, you will only improve up to a certain point. If it is a really hot day you can also just go by your heart rate instead of your pace. With VO2 max workouts, the goal is to accumulate time running with your heart rate at 95% or higher of your max heart rate. Max heart rate is generally 220 minus your age, although that can vary.
An ideal VO2 Max workout would include 2.5 to 5 miles total of running at this pace. So, for example, you could run 6 x 800 meters which would give you 3 miles total. Or 4 x 1600, which would give you 4 miles total. The possibilities are endless.
Each interval should also last between 2 and 6 minutes. Your speed will determine your distance here. If you are running 6:00/mile pace, you could run anywhere from 600 meters per interval all the way up to 1600 meters. But if you are running slower than that, 1600 meters would be too long of an interval, and you should choose a shorter distance. (perhaps 800, 1000, or 1200 meters)
The rest between each interval is important too. Recovery time should last for 50 to 90% of the time of the interval itself. So, for example, if you are running 1600 meter intervals in 6:00, you should recover for somewhere between 3:00 and 5:30 between each one. Recovery time can include easy jogging or just walking and stretching, although easy jogging is preferable.
*6 x 800 meters
*5 x 1000 meters
*4 x 1200 meters
*3 x 1600 meters
3. Lactate Threshold: Sometimes known as a tempo run - a run of 20 to 40 minutes (could also be broken into intervals) at your 15k to half-marathon race pace, which trains your body to delay the accumulation of lactic acid. Also improves your concentration, toughness, and ability to sustain a hard pace in a race. If it is a really hot day, you can also go by heart rate, and run at an effort that requires 85 to 92% of your maximum heart rate.
* 20 to 30 minute tempo run at LT pace
* 4 x 1 mile at LT pace with 2 minute recovery jog in between each interval
* 3 x 1.5 mile at LT pace with 3 minute recovery jog in between each interval
* 2 x 2.5 miles at LT pace with 5 minute recovery jog in between each interval
4. Long runs: Quite simply - a long run - which helps to build endurance. Should generally be run 1:30 to 2:30 per mile slower than your 5k pace (or :45 to 1:30 per mile slower than your marathon pace). If you want to go by heart rate, try to stick somewhere between 70 and 85% of your maximum heart rate during the run. A good strategy is to start out at the slower end of your pace range and gradually work your way down to the faster end for the last 2 or 3 miles of a long run. For example, on a 16 mile run, I might run the first 6 miles at 8:20 pace, then speed up to 8:00 pace during the middle, and finish the last few miles at 7:40 pace.
One of the most common mistakes people make in training is running their long runs too fast. This puts you at greater risk for injury and leaves you too tired to get in effective VO2 max and lactate threshold runs later in the week. The distance of a long run can also vary depending on which race distance you are training for. For example, the aforementioned 16 mile training run is probably longer than you need in training for a 5k.
5. Recovery runs: Easy runs which help you recover from previous hard days to allow top effort on future hard days, yet still allow you to accumulate weekly mileage. People also commonly make the mistake of doing these runs too fast. Just let your legs recover, and save your energy for VO2 max running, lactate threshold runs, and other key workouts later in the week. Recovery runs should be completed at less than 75 percent of your maximum heart rate.
A good training plan should include all of these types of running at various times. However, some workouts are more important for certain race distances. For example, long runs are obviously more important in training for a marathon than in training for a 5k. And VO2 max workouts are more effective in helping you improve your 5k time than your half-marathon time.
Certain types of running also become more or less important at various phases of a training plan too. For example, lactate threshold runs are more important early in a marathon training plan, whereas VO2 max workouts become more important as you get closer to the race.
But the key to successful racing is to implement all of these types of workouts into your training. For example, even though basic speed is the least important factor in distance racing, it would be to your detriment to ignore it. It is also important that, whichever type of workout you are doing, you understand the purpose of that workout and exactly what you are trying to develop.
Another key is to be patient when increasing your mileage or intensity (training pace). In Daniels' Running Formula, Daniels explains that a major key to success is to avoid injury. He writes that, "In a sense, the runners we send to the Olympics are not necessarily our top runners, but they are very good runners who have avoided injury at critical times." A good general rule to follow is to avoid increasing your mileage by more than 10% per week, and to take a "recovery" week with lighter mileage every fourth (or even third) week.
I hope this information helps. Good luck with your training. Stay healthy, train smart, and race fast!