ou may not be a marathon champion or even finish in the top 100 in local 5-K races. But if you enjoy running, you may still want to train to become faster. The thrill of a faster race or the accomplishment of beating your personal record are the rewards for some punishing speed drills. The "killer" speed sessions such as those below can help improve your running speed, but don't attempt them if you're not in shape to do so. You should be running at least 15 to 20 miles a week for four to six months before attempting the following speed drills. These drills should only be done once every two weeks or so as a substitution for your regular workout. And don't do the speed workouts when you're tired, injured or training very hard. Warm up with a one- to two-mile jog, then stretch your legs. After your workout, cool down so your muscles won't cramp or tighten. Run a couple of miles, then stretch again. After a speed workout, give yourself at least two days of light or no training to recover. These are good early-season drills to increase your leg speed. But avoid them if you have knee problems. Select a hill that's about 1/8 mile long. Jog up the hill at an easy pace. Then run down the hill with the goal of increasing the frequency of your stride (your leg speed). Don't try to lengthen your stride. Lean your body forward slightly, while running smoothly. Avoid "pounding" down the hill, which is hard on the quadriceps (front thigh muscles) and knees. Don't overdo it. Four to six repetitions are sufficient. Run three 300-meter intervals as fast as you can. Jog 100 meters after each one. Next, run 400 meters at a slightly faster pace than the 5-K race pace, then jog or walk for 400 meters. Repeat the 300- and 400-meter sets four times. Then add one or two each interval session until you can do eight. Run 800 meters at a 10-K race pace, then jog for 2 minutes. Run 400 meters at your 5-K race pace, then jog for 60 seconds. Then run another 400 meters at a slightly faster pace. Without resting, run 800 meters at a 5-K race pace. Then jog easily for 4 minutes and repeat the 800-400-400-800 sequence. © Your HealthStyle, 2000.