Saturday, September 22, 2007

Stretching for healthier knees

In previous posts we have looked at the way in which knee injuries might be prevented through balance or proprioception training, at how women's knees are prone to injury and also how stretches should be avoided prior to exercise.

This study below is useful in that it indicates how appropriate stretching might also contribute to healthier knees.

If you have bad knees you might want to consider adopting a regular stretching routine of the muscles mentioned in this article - quads, hamstrings and adductors. If they are tight they might be throwing out the positioning of the knee. Stetching should be about stretching the tight muscles to restore balance and function to the body.

Effect of static stretching of muscles surrounding the knee on knee joint position sense

Background: Muscle stretching is widely used in sport training and in rehabilitation. Considering the important contribution of joint position sense (JPS) to knee joint stability and function, it is legitimate to question if stretching might alter the knee JPS.

Objective: To evaluate if a stretch regimen consisting of three 30 s stretches alters the knee JPS.

Design and setting: A blinded, randomised design with a washout time of 24 h was used.

Subjects: 39 healthy students (21 women, 18 men) volunteered to participate in this study.

Methods and main outcome measures: JPS was estimated by the ability to reproduce the two target positions (20° and 45° of flexion) in the dominant knee. The absolute angular error (AAE) was defined as the absolute difference between the target angle and the subject perceived angle of knee flexion. AAE values were measured before and immediately after the static stretch. Measurements were repeated three times. The static stretch comprised a 30 s stretch followed by a 30 s pause, three times for each muscle.

Results: The AAE decreased significantly after the stretching protocols for quadriceps (3.5 (1.3) vs 0.7 (2.4); p<0.001), hamstring (3.6 (2.2) vs 1.6 (3.1); p = 0.016) and adductors (3.7 (2.8) vs 1.7 (2.4); p = 0.016) in 45° of flexion, but no differences were found for values of the gastrocnemius and popliteus muscles in this angle and for the values of all muscles in 20° of flexion (p>0.05).

Conclusion: The accuracy of the knee JPS in 45° of flexion is improved subsequent to a static stretch regimen of quadriceps, hamstring and adductors in healthy subjects.


Scott Kustes said...

Right on Chris. I used to have persistent, mild right knee pain. I also used to have chronically tight hamstrings. While I'm still not extremely flexible, dedicated hamstring stretching, along with weighted, full-depth squats (after finding CrossFit) have done away with it. Now, if I feel a touch of ache in my patellar tendon, I can stretch out my right hammy and it goes away.

By the way, just found your site and love it. Keep up the awesome work.

Scott Kustes
Modern Forager

Chris said...

Thanks for the comment - yours is a blog I enjoy too.