Thursday, July 4, 2013

Stretching the Limits for Fitness and Performance



Stretching the Limits of Fitness and Performance

Stretching is a matter that requires understanding what limits body movement, and how mobility is required for the fitness or sports performance. There are many misconceptions of the benefits of stretching, and how much flexibility is required. The application of a stretching program must take into consideration the individual needs of the individual, and the sport specific demands of movement and how this maximizes the health and performance in this activity.


Stretching the Limits


You are not stretching to be the next gymnast, nor do you need to keep up with the person in front of you in your Yoga class. Stretching is about mobility. This allows muscles to move, and therefore, joints to move. You can be too flexible, or hypermobile, and if not balanced with stability of the joints, and muscle strength, injury can be sustained. I have encountered many individuals that can palm their hands to the floor, but also need spinal fusion.

An understanding of muscle anatomy, physiology and biomechanics is required to better provide an individualized program. For example, it is important to know if the muscle you are "stretching" crosses one joint, or two.

A muscle can be limited by overuse of some movement, or position of a muscle. This can create hypertonicity, or excitability, of that muscle that will then limit movement when this muscle is placed on stretch, or elongated. For example, muscles that are chronically shortened, such as the hamstrings during prolonged sitting, become tight. It should be noted that those muscles that are chronically lengthened, maybe due to postural positioning such the rounded shoulder blades in sitting, can become weak, or susceptible to fatigue. This can be the cause of back and neck pain.

If there are muscles groups that tight on one side of the body, you can count on having tightness on the other side of the body. You will often find that if the hip flexors are tight, the low back extensors will also be tight.

Stretching can reduce the risk of injury

Stretching has not been shown to be effective at reducing the incidence of overall injuries.(1) While there is some evidence of stretching reducing musculotendinous injuries,(1) more evidence is needed to determine if stretching programs alone can reduce muscular injuries.(2)
(1) Small K, Mc NL, Matthews M. A systematic review into the efficacy of static stretching as part of a warm-up for the prevention of exercise-related injuryRes Sports Med. Jul 2008;16(3):213–231.
(2) McHugh MP, Cosgrave CH. To stretch or not to stretch: the role of stretching in injury prevention and performanceScandinavian journal of medicine & science in sports. Apr 2010;20(2):169–181.

Stretching can improve range of motion

  • Stretching can increase joint extensibility where there is actual change in joint range of motion related to increased muscle length.
  • Stretching can also increase tolerance to stretch. In this case muscle length may actually stay the same, but a greater tolerance to muscle force is gained.
Stretching can create increased muscle length 
  • Static, or sustained hold Stretching is most beneficial when held for 15-30 seconds.

Stretching must be performed daily to maximize the benefit

  • To increase the extensibility of a muscle a daily regimen of stretching must be used.

Stretch dynamically before activity, and static after activity

  • This statement is only generally true. It can be generally applied to runners and jumpers that engage the muscles in that require more force, and where overall endrange movement may not be required. Getting the muscles warm, and ready for activity is the goal.
  • In sports where flexibility, like gymnastics and dancing, the use of static stretching can have more of an impact on joint and muscle extensibility. These athletes will engage in daily stretching routines that prepare the joints and musculotendinous structures for endrange, body postures and positions vital to the sport.

                                      


Stretching alone does not prepare for the exercise, or activity
  • Warming the muscle with light movement of the joints(dynamic warm-up) or running prepares the body for exercise and sports activities.

Stretching statically requires prolonged holds with low level pain

  •  Over stretching, or stretching to the point of increased pain beyond mild will cause the muscle to contract, protecting the muscle. This is counterproductive.
Stretching does not have to Hurt

Stretching muscles with rotation creates more elongation of the muscle


  • All muscles provide some rotational component of movement to the extremity. This is based on the orientation of origin and insertion of the muscle ends. When the muscle contracts it creates some multi-planar movement of the joint. For example, when the medial hamstrings contract creates medial rotation of lower leg. To stretch the medial hamstring there must be some lateral(external rotation) of the leg as the straight leg is pulled back. 

PNF Diagonal Stretch for Hamstring
with adduction and external rotation


Stretching muscles prior to sprinting and jumping can decrease performance.






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