To stretch or not to stretch? Part 1: Static Stretching.

Stretch

Static Stretching is believed to be an essential part of any warm up, warm down and during most exercise regimes. It is widely accepted that stretching minimises injury, decreases delayed onset muscle soreness (the soreness you feel after working out) and in some cases increases, improve performance.

I’ve never been fully convinced on the issue of static stretching. Over the years I’ve read interesting studies from both points of view, and throughout my professional soccer career I’ve worked with coaches who have shared their differing philosophies on the issue. I hate being a fence sitter, so determined to come up with an answer, I commenced my own research project.

What is stretching?
Throughout this article I will be discussing the major components contributing to the process of stretching. In the interest of clarity I will lay out a few definitions. If you’ve ever participated in a group training or personal training session your coach will most likely have taken you through a few drills at the beginning and end.

Stretching can be defined as the elongation of muscle fibres through various techniques to increase joint range of motion. There are four different types of stretching:

  • Static Stretching is a type of stretch whereby a person stretches the muscle until a gentle tension is felt and then holds the stretch for thirty seconds without any movement or bouncing. This is the most common type of stretching, and will form the focus of part 1 in the series of stretching blogs.
  • Ballistic stretching is a rapid bouncing stretch in which a body part is moving with momentum that stretches the muscles to a maximum. Muscles respond to this type of stretching by contracting to protect itself from over extending.
    Dynamic stretching is a walking or movement stretch. By performing slow controlled movements through full range of motion, a person reduces risk of injury.
    Proprioceptive neuromuscular facilitation (PNF) is a type of stretch for a particular muscle and its specific job, so resistance should be applied, and then the muscle should be relaxed.

Flexibility Vs. Full Range of Motion. It’s apples and oranges.
This is where things get a little more complex; it is widely accepted that flexibility can be achieved by static stretching and is optimal for injury prevention, however flexibility doesn’t necessarily mean you have the capability to move load through the range of motion, flexibility ONLY means you can move through the range of motion. So many people may appear to be very flexible in their yoga class (while static stretching), however when weight or load is added they cannot perform the same range of motion.

The optimal situation for an injury-free exercise regime is for the subject to possess the ability to move load throughout the full range of motion, which would enable them (for example) to achieve proper depth in a squat or to push a weight correctly overhead. This is called functional range of motion. Flexibility without load is simple range of motion.

This functional range of motion cannot be achieved through static stretching, however can be achieved through a variety of different methods which I shall be following up in part 2 of this stretching series. Some top-line examples include:

  • Myofascial release trigger pointing
  • Warm up
  • Muscular activation drills
  • Mobility techniques and exercises
  • Performing movements with load forcing the body into the range of motion or stretching with load attached

Posessing flexibility (or simple range of motion) through a joint can be beneficial and detrimental at the same time.

Having the ability to move through full range of motion does benefit us immensely when pursuing greater muscle activation when we lift or move. Some people can, through sheer genetics, be hyper-mobile (you know those freaks who can put their limbs in ridiculous positions) or incredibly stiff (the guys who struggle to do their shoes up).

However, neither end of the spectrum is optimal. If you were to sit on the proverbial seesaw, middle-ground is always best. Most of us would sit on the stiff side, but this is not necessarily the worst end to be on as being too flexible can be detrimental to your health. This Most of us would sit on the stiff side, but this is not necessarily the worst end to be on as being too flexible can be detrimental to your health. This is because hypermobility around the joints can promote dislocation and numerous joint related injuries. I am personally privvy to this genetic predisposition, and let me tell you – it’s awful. After-all, you can always get flexible but you can’t always get stiff.

Is static stretching really that important in injury reduction and prevention?

From personal experience
My journey commenced with a review of my own personal experience with injuries and stretching. I will always be the first to admit (my colleagues would remind me if I didn’t) that in the last few years, I have not been very vigilant at warming up, trigger pointing or stretching before/after any workout. I will perform the odd trigger pointing session usually once I’ve left it a bit too long and am starting to feel the onset of an injury but generally, I just don’t rate it. My lack of stretching or trigger pointing comes from a combination of laziness and the fact that I am busier than a one arm brick layer in Baghdad, so when it’s time for a workout I try to get in and out without chewing up too much time.

When I overlay my bleak history of stretching with the number of injuries I have sustained, I think I’ve gotten away fairly well off. I have had the occasional minor injury here and there, given I train approx. 7-8 times per week at a decent intensity.
I realise that up until this point everything I have said is subjective, so don’t get up in arms just yet – especially not for this next bit.

During my time as a professional football (soccer) player, I was completely vigilant. I warmed up, trigger pointed, static-stretched, underwent numerous warm up/down protocols and performed activation drills. Some may say that this could be put down to sheer coincidence, but during my career I sustained 3 major shoulder injuries and subsequent reconstructions, a knee reconstruction, several hamstring and groin strains as well as a few minor lower back injuries. I realise that to draw a correlation between warm up and warm down protocols and my injuries is pretty unfounded, but when I overlay this with the research that I have read, it has certainly helped to justify my experience.

Let’s hear what the experts have to say…
To put it frankly, there is NO empirical evidence to suggest that static stretching (simple range of motion) offers preventative mechanisms or attributes for injury (Witvrouw, Mahieu et al. 2004). If you can find a study (peer reviewed please) that suggests otherwise, I would love to see it. Send to matt@hammerperformance.com.au

Static stretching is primarily the most ineffective way of stretching as most research concludes that stretching for long periods of time in a static fashion can actually increase muscle damage post exercise which actually increases injury prevalence, especially if you do more exercise later in week (McHugh and Cosgrave 2010). Static stretching also decreases cross bridge attachment sites as well altering Ca2+ balance in the muscle decreasing both muscle strength and power (Safran, Garrett et al. 1988). And finally, every time a static stretch is performed in a workout, it decreases muscle temperature which increases the risk of rigidity when entering the exercise again.

The bright side…
Not all research paints a terrible picture when it comes to stretching. Dynamic, ballistic and PNF stretching all can be advantageous prior to any exercise regime. There has been some evidence to suggest that if the right protocols are performed, reduction in injury is apparent.

I will be covering off the ‘right protocols’ that this research discusses in my follow-up blog or part 2 in this series over the coming weeks.

Conclusion
At this point, the research that I have covered suggests that static stretching is a waste of time when it comes to reduction of injury. This concerns me as static stretching is the most common form of stretching that is performed by general publich of gym-goers and exercise enthusiast’s. Stay tuned for part 2 of the stretching series to learn more about they types of stretching that can be advantageous.

References
McHugh, M. P. and C. H. Cosgrave (2010). “To stretch or not to stretch: the role of stretching in injury prevention and performance.” Scandinavian Journal of Medicine & Science in Sports 20 (2): 169-181
Safran, M. R., W. E. Garrett, et al. (1988). “The role of warmup in muscular injury prevention.” The American Journal of Sports Medicine 16(2): 123-129. This study is an attempt to provide biomechanical support for the athletic practice of warming up prior to an exercise task to reduce the incidence of injury. Tears in isometrically preconditioned (stimulated before stretching) muscle were compared to tears in control (nonstimulated) muscle by examining four parameters: 1) force and 2) change of length required to tear the muscle, 3) site of failure, and 4) length-tension defor mation. The tibialis anterior (TA), the extensor digitorum longus (EDL), and flexor digitorum longus (EDL) mus cles from both hindlimbs of rabbits comprised our ex perimental model.Isometrically preconditioned TA (P < 0.001), EDL (P < 0.005), and FDL (P < 0.01) muscles required more force to fail than their contralateral controls. Precondi tioned TA (P < 0.05), EDL (P < 0.001), and FDL (P < 0.01) muscles also stretched to a greater length from rest before failing than their nonpreconditioned con trols. The site of failure in all of the muscles was the musculotendinous junction; thus, the site of failure was not altered by condition. The length-tension deforma tion curves for all three muscle types showed that in every case the preconditioned muscles attained a lesser force at each given increase in length before failure, showing a relative increase in elasticity, although only the EDL showed a statistically significant differ ence. From our data, it may be inferred that physiologic warming (isometric preconditioning) is of benefit in pre venting muscular injury by increasing the and length to failure and elasticity of the muscle-tendon unit.
Witvrouw, E., N. Mahieu, et al. (2004). Stretching and Injury Prevention.” Sports Medicine. 34(7): 443-449




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