Runners need active stretches.
The Problem with Static Stretches
Most static stretching, over a period of time, permanently elongates the relevant tissues. Sometimes this is useful. For example, if you have a limited range of motion due to a shortened muscle or ligament (perhaps due to an injury), static stretching may be the best method to elongate those structures. But if your range of motion is not limited, then static stretching may even be ill advised. Too much movement may compromise the integrity of that joint making it easy to injure. In fact, excessive flexibility is a risk factor for injury in itself.
When you stretch a muscle, it may contract in an involuntary effort to limit the range of motion in order to protect the muscle from over-stretching. This is your stretch reflex and it is part of your neurology that protects your joints from damage. When you perform a static stretch, you must voluntarily relax these muscles in order to override the stretch reflex. In static stretching, the nervous system is literally knocked out so that it can't activate the muscles in the same way they respond to motion.
In running, however, the nervous system plays an extremely important role. Running is a neuromuscular activity that requires constant firing of the nerves to activate the muscles producing leg and arm actions in a very active process. To truly prepare the muscles and joints for running, you must do something that activates them for running.
Range of motion in running at both slow and fast speeds depends on how strongly the muscles contract to move the limbs. An active range of motion depends more on the strength of the muscles involved than the degree of flexibility.
It is the muscular contraction that creates the force needed to move the limb through its potential range of motion. The muscles and corresponding nerves must be activated in the same way they are used in your running stride. During a static stretch the muscles are relaxed. In contrast, in dynamic movements the muscles perform in running strides. The forces experienced in such movements far surpass those in static stretching. As a result, you aren't preparing yourself to cope with forceful movements if you do only static stretches.
What the Runner Really Needs--Functional Range of Motion
Another way of looking at range of motion is to equate the stretch with exactly what takes place in the joint during running movements--this is functional range of motion. Does the stretch duplicate what takes place in the joint in relation to running? Does the stretch duplicate the type of muscular contraction that is elicited when you run?
Stretching and flexibility training are not necessarily synonymous and you can differentiate between the different types of stretching and flexibility exercises in order to perform the most appropriate and effective means of increasing functional range of motion. Static stretching increases static joint mobility rather than achieving functional range of motion in the shoulder, hip, knee and ankle joints, as they are involved in running. Active stretches involve strength as well as flexibility, thus minimizing the risk of injury and preparing muscles and joints for running.
Active Stretches-- The Runner's Solution
During active stretches the joint is simultaneously stretched and strengthened throughout its range of motion. Full range exercises against resistance offer the greatest functional increase in range of motion--flexibility for running. Active stretches stretch the muscles and tissues and activate them in preparation for running. When you do active stretches with resistance, you gain strength and flexibility simultaneously in the same exercise. It is a useable range of motion in which the muscles are capable of moving the limb through the range of motion developed for your running stride.
The major muscular contraction involved in active stretches is the eccentric contraction. In this contraction, the muscle develops tension while the overall length of the muscle increases by stretching under tension. For example in running, when you experience touchdown there is slight flexion in the ankle, knee and hip joints to absorb and withstand landing forces. As soon as the foot touches the ground, the muscles and tendons immediately tense to handle impact forces and to accumulate energy for the next push off.
There are many forms of active stretches that range from relatively simple stretches to very complex, explosive type stretches. However, in all cases, active stretches involve muscular work during the stretch. This is needed not only to ensure maximum joint safety but also to prepare the muscles for running.
Studies have shown that the landing forces in running can often be up to ten times your body weight, depending upon running speed and landing style. These are huge forces that the muscles and joints must be able to handle. The joints and their associated tissues must be able to cope not only with predictable but also unexpected, irregular, and sudden loads. If the tissues are unable to dampen shock loading adequately or with optimal speed, like efficient shock absorbers on a car, then the hard and soft tissues of the body may be damaged. Tissues that are either too soft or too stiff can cause damage to the body during shock loading. Active stretches can help to optimize your body's shock absorbing system, not only stretching the muscles and connective tissues appropriately but also warming up and strengthening your muscles, preparing your body for action.
("Running & FitNews" Editorial Board Member Michael Yessis, Ph.D., is president of Sports Training, Inc. at www.DrYessis.com. For more exercises, read his book Explosive Running, Using the Science of Kinesiology to Improve Your Performance, 2000, contemporary Books, Chicago, IL, $17.95, 173 pages. It is available at a 20% discount by calling 800-776-2732 or visit www.americanrunning.org)
RELATED ARTICLE: Active Stretches You Can Use!
* Touchdown and push-off use the muscles and support structures of the foot and lower leg. You need strength and flexibility in the calf, the Achilles tendon and the arch of your foot. The best stretch to improve range of motion for these is the standing ankle extension. Lean into a wall, hands at shoulder height, feet two to four feet away. Feel a stretch at the back of your ankles. As you lean into the wall with feet flat, feel the stretch for a count of one or two, then rise up on the balls of your feet and hold for a count of two. Lower your heels and repeat, up 1-2 and down 1-2.
* A running stride does not require a great range of motion at the knee. There is some bend at the knee in landing but 45 degrees is more than enough to prepare for running. The best exercise to stretch and warm up the muscles and tissues needed for the support phase is the squat stretch. Stand with your feet hip-width apart, feet flat on the ground at all times, trunk erect. Keep the back in its normal curvature (slightly arched lower back) throughout the move. As you slowly squat, your hips should move slightly to the rear and your trunk should lean forward, keeping the spine stable. Stop well before your thighs are parallel to the ground, rise up and repeat with the same up 1-2 and down 1-2 count.
* Hip flexion and extension play key roles in determining running speed, controlling stride length, push-off, and stride frequency. Hip-flexor flexibility is very important in stride length and hip extensor (hamstring) flexibility determines how high the thigh raises before pulling back. The lunge stretches and warms the hip flexors. Stand with feet hip-width apart and take a very long step forward, planting your foot with the toes forward. Keep the rear leg straight but relaxed with your weight supported by the front leg. Hold for a count of two and push back to standing and repeat with the other leg, forward 1-2 and back 1-2.
* Static Stretch--Holding a particular position for 30 or more seconds to stretch the muscles and connective tissue surrounding the joint. The key to successful execution of these stretches is to hold the position while relaxing the muscles as much as possible to get a gradual increase in the range of motion.
* Ballistic Movement--Forceful, powerful movements.
* Concentric Movement--In a concentric contraction the muscle shortens to produce movement.
* Eccentric Movement--In an eccentric contraction the muscle lengthens and develops tension to guide the movement and to stop it.
* Agonist and Antagonist Muscles--Muscles that act in opposition to one another and yet act together to control movement.
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|Publication:||Running & FitNews|
|Article Type:||Brief Article|
|Date:||Dec 1, 2000|
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