Анатомия бега (2010,иностр

Plyometrics

The term plyometrics is mysterious to many distance runners, although it is a common training tool for many elite distance runners, middledistance runners, and sprinters, most professional athletes, and many athletes rehabilitating from injuries. For the noninitiated, it sounds like, and at times is represented as, a hyperspeed method of improving performance. Just perform plyometrics, drink amino acid-laced recovery drinks, and voilà, instant performance improvements.

By definition, plyometrics means measurable increases, in this case through body-weight exercises. Because it is the use of strength, not raw strength, that contributes to speed development, plyometric exercises have one main goal: the conversion of strength to speed by generating a large amount of force quickly. Plyometric exercises train the neurological and muscular systems to increase the speed at which the body’s strength can be used. By performing plyometric exercises, runners can measurably improve running performance, but not in the way they may think.

A by-product of the development of muscular power is an improvement in running economy. Running economy is the cost, or amount of oxygen, required to maintain a defined pace. The less oxygen used to maintain a certain pace relative to other runners or your previous measurement, the better the running economy. It does not quantify the efficiency of running form (the terms are often confused), although running form may affect running economy.

Plyometric exercises trigger improved running economy through recruitment of muscle fibers in a way that distance training does not. A plyometrically trained athlete’s muscle contractions are shorter in duration; because less strength is required to perform the contraction (a result of both increased strength and neurological development), running economy improves. This chain of events leads to faster performances caused by the delay of muscle fatigue.

But, unlike DWR, plyometrics cannot be substituted for running training to improve performance for distance runners. Although DWR has an impact on LT and VO2max, plyometric exercises train the neuromuscular systems with almost no impact on the cardiothoracic

systems described in chapter 2. Without running training, plyometric training could not sustain improvements in running performance. There is debate about the phase of training in which plyometrics should be incorporated. There are no definitive answers, but we suggest

one plyometric session per week during lactate training and two sessions per week during VO2 max training. The workout should be done before the LT or VO2 max workout takes place, in a separate training session if possible, and not on recovery days.

The plyometric workout should be sufficient in duration to develop muscular fatigue, but not so difficult that the running workout is compromised. The neurological component of the workout is as important as the muscular strength derived from exercises, so performing the exercises to exhaustion can overload the muscles for the workout to follow and performance improvement could be hindered.

Following are four beginning plyometric exercises that can be incorporated into a running program. The exercises do not all meet the true definition of a plyometric exercise (eccentric muscle contraction, inertia, concentric contraction), but because they do involve explosive musclecontraction movements, most current training programs include them as plyometric drills. These can be performed all in one session, as one set only, as multiple (two or three) sets of each for a heavier day, or as just one or two exercises with a single set for an easy preworkout. Limit the total number of repetitions or touches to no more than eight per exercise (except for box steps, which can be done in one-minute intervals at varying speeds) and the total number of sets to no more than five per exercise.

The number of exercises performed and the number of reps or touches are dependent on many factors: The familiarity of the runner with plyometric exercises, the difficulty of the workout to be performed after the plyometric session, and the runner’s fitness. Following the exercises are some guidelines for performance.

Frogger

Midair position.

Running Focus

The frogger is a propulsive exercise that requires the athlete to explode from the start position, engaging the quadriceps, hamstrings, and glutes. Although it has a very practical application for sprinters (the improvement of the starting motion from a block), the frogger, like all plyometric exercises, can also aid the distance runner by increasing running economy by strengthening the impacted muscles, leading to less energy consumption during distance running.

A-Step Depth Jump Start position.

Landing position.