Are You Leg Speed Training?

For a finish-line kick worthy of the free photo your race likely offers, consider leg speed training—a peculiarly narrow subset of training that will help you overtake your contenders in a triumphant, final surge. Although we each have an innate amount of leg speed, all runners can improve upon it by undertaking two training subtypes: neuromuscular training (NMT) and lactic acid tolerance (LAT).

At its essence, leg speed training is any workout in which near-maximum running speeds are maintained for 90 seconds or less. In NMT, the object is to never build up blood lactate, and so repeats of fast running (mile race pace) should be kept at less than 30 seconds. For a similar but alternately focused biomechanical analysis of exertion level and optimal gains, see the discussion of interval training, “Keep Interval Intensity Steady,” in this issue. By keeping NMT repeats under 30 seconds, you are ensuring that your primary energy source is the ATP-creatine phosphate system, which produces very little lactic acid. The rests between these short bouts should be long enough to completely remove from the muscles any lactic acid that has been produced.

The Muscles Remember
The reason to avoid lactic acid build-up when performing NMT is that the goal is to train the brain and nerves to best activate the running muscles. Calling upon more muscle fibers in the most coordinated fashion possible requires, then, that fatigue is avoided. To continue better defining these muscle movements, as well as making them faster, your form must remain intact. Lactic acid interferes with neuromuscular recruitment, resulting in poor technique. You therefore need a full recovery between bouts—you should be able to run your last few repeats faster than your first few.

With the goal of pushing off forcefully and generating the highest possible velocity across the ground, leg speed training improves your ability to sprint for short distances. Always make sure, then, that once your leg has swung fully forward, you pull it down and back as your foot makes contact. This willful paw-back is a lot like the arm movements in swimming the crawl stroke. By focusing on that backward push and not merely the forceful pull-down, you’ll avoid simply bouncing up and down and rather propel yourself across the ground.

Here is a sample NMT workout known as Straights and Curves. With each repeat, make slight adjustments to arm and leg movements, perhaps kicking higher toward your gluteals in one bout and bringing your knees higher in the next. Subtle shifts in your “lean” can also help you find the form that works best for you, increasing speed and reducing effort. Don’t consciously focus on increasing your stride length—trust paw-back and push off to optimize stride.

On a track, after a thorough 20 minute warm-up, simply jog the curves and sprint the straightaways. Start with four to six laps (12 sprints) at the beginning of your base training phase. Progress to a maximum of 10 laps, or 20 total sprints. Try medium-intensity for the first three sprints, gradually increasing speed until the last two to four sprints are at near-maximum speed. Jog the curves very slowly. Give yourself 45 to 90 seconds between repeats. Cool down with slow jogging for at least 10 and even up to 30 minutes.

Perform this workout once a week for eight weeks, increasing by up to two laps most weeks. After this period, you can begin to add LAT workouts once every two to three weeks in addition to this weekly NMT workout.

The Muscles Tolerate
LAT training teaches the muscles to better tolerate lactic acid build-up, the well known end result of carbohydrate conversion into energy. The idea, then, is to stay above your anaerobic threshold so that lactate production outpaces removal. Because this type of training induces the best adaptations in lactate capacity, use, and removal by varying the amounts of blood lactate with which you perform bouts, these workouts can be somewhat loosely structured. As long as you run at near-top speed (800-meter race pace) for between 30 and 90 seconds, you can use any combination of durations you like. Repeats longer than 90 seconds are ill advised because they necessitate a slower pace and form will likely deteriorate.

You should not allow recovery times longer than two or three times the duration of the repeat. You want time to remove most, but not all, of the lactic acid. For 30- to 45-second repeats, twice the duration should do the trick. For 45- to 90-second bouts, recovery jogging at three times the bout duration works best. The goal of LAT training is to produce a lot of lactic acid, remove it, and produce it again, teaching the muscles to both operate with blood lactate as well as enhancing your ability to get rid of it. The result is an increased ability to sustain leg speed.

Try to maintain or increase your speed progressively with each repeat throughout the workout. Many runners enjoy LAT training as “anywhere” runs. Similar to the unstructured running known as fartlek, these workouts can take place in a field, on trails, along roads or on a track if you prefer.

Keep Them Separated
Don’t try and perform both types of training in the same workout. Also avoid LAT training in the base period. This will interfere with that training phase’s goal of enhancing aerobic endurance. Most runners and coaches feel that between 800 and 3,000 meters per leg speed workout is sufficient. This naturally varies with your goals and years of experience. LAT training sessions tend to cover longer distances, such that perhaps NMT for 1,000 meters and LAT for 2,400 meters per session may work for you. Other coaches prescribe leg speed training distances as a percentage of your usual race distance. For 800 to 1500 meters, 200% of the distance is deemed adequate; 3000 to 10,000 meters requires only 100% of the race distance.

Leg speed training works with the smaller, accessory muscles not ordinarily recruited at more moderate speeds, as well as the major muscles and tendons used in running. It is a great way to improve turnover and velocity, and you’ll find it can improve all areas of your running fitness. And once you’ve fine-tuned your sprinting form, additional leg speed training consolidates this technique in your neural patterns, continuing to hone your surging skills for that final quarter-mile sprint to the tape.

Run Strong, ed. by Kevin Beck, 2005, “Creating Leg Turnover and Raw Speed,” by Greg McMillan, MS, pp. 25-40, Human Kinetics, Champaign, IL

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