Tyler Robbins Fitness

B.Sc. Biochemistry, Certified Strength and Conditioning Specialist (CSCS), Certified CrossFit Trainer (CCFT/CF-L3), USA Weightlifting Level 1

Filtering by Tag: PNF

Does static stretching help?

Well, according to an article published over at Runner's World, apparently not! To be honest, I don't really want to link to the article because I think it is kind of bull, but if I am going to write about it then I better link to it. You can also get the actual study being examined here.

Ok, let's break this down. I really think this author took these research results and took them completely out of context.

First, they end up mostly agreeing with a body of previous research suggesting that increased range of motion following a prolonged stretching program is mainly the result of increased tolerance to the sensation of stretching, rather than actually loosening the muscle-tendon unit. That is, you get better at pushing a little farther when you're at the extreme edge of your range of motion.

Our muscles have a defence mechanism called the Golgi Tendon Organ which senses changes in muscle length. If your muscle is lengthening too fast or too far then you have a reflexive action that essentially locks things up and won't let you go any further. It takes a long time (per session as well as number of stretch sessions) to be able to relax your body enough to get past this defence mechanism. This is why we hold stretches for a while or use things like PNF stretching, using a contract-relax cycle to help inhibit this reflex.

This study was done for 3 weeks.

Let that sink in for a second....I stretch all the time and I witness almost no measurable changes in my flexibility in 3 weeks either. It takes months and years of consistent effort to get and maintain flexibility. Just as someone who gets up off the couch and starts training for a 5km run, you are not going to see immediate changes in your range of motion or flexibility.

Not only that, but this study was conducted on the calves. Off the top of my head I'm quite certain the ankles have the least amount of range of motion out of all of the body's joints. I guess it was an easy selection because the ankle really only bends in one direction (minor inversion/eversion).

Static stretching helps improve circulation, aides in recovery, but most of all, it is intended to increase range of motion.

I just got back from a USA Weightlifting course over the weekend in Rochester. One of the key contributing factors for weightlifters (can be applicable to other sports too) is the fact that flexibility and full joint range of motion is not only critical to success, but strongly promoted for safe training. Weightlifters are some of the most flexible athletes in the world!

Having said all of that, static stretching should not be done prior to a workout. It has been proven to not reduce risk of injury and can even decrease strength and power performance. However, stretching at the end of workouts when the body is still warm is still highly recommended to increase range of motion to properly perform exercises safely and effectively.

To be honest, this is an interesting topic of research/discussion. How important is flexibility? I don't believe everyone needs to have the flexibility and range of motion as say a gymnast, however an increase range of motion for the average population would probably benefit those at risk for injuries.

Take back injuries, for example. I would love to see a study conducted on improving flexibility of things like the lower back, hamstrings, hip flexors, abdominals, gluteals, etc. (common low back pain causers) over a long-term study (longer than 3 weeks) in order to see the benefits of flexibility training.





Proprioceptive Neuromuscular Facilitation (PNF) Stretching

Proprioceptive Neuromuscular Facilitation (PNF) stretching was first developed to help rehabilitate patients by relaxing muscles with increased tone or activity. These principles can be applied to any individual, however, and although it is generally recommended to perform these techniques with a partner, using tools such as stretching bands or belts can help stretch certain body parts while still maintaining PNF stretch techniques.

PNF stretching may be superior to other stretch techniques because it facilitates muscular inhibition by using both passive and active movements (concentric and isometric) and muscle actions. The biggest downfall of these stretch techniques however, is that many body parts require a partner to help achieve PNF stretching, and they must be done with correct form and technique in order to work properly.

There are 3 main types of PNF stretches that I have detailed below. In each technique, the first phase incorporates a passive pre-stretch that lasts 10 seconds. The initial pre-stretch is then followed by a 2nd and 3rd phase which varies by technique.

Hold-Relax

Following the initial 10-second pre-stretch, a force is applied to the muscle in question while the individual being stretching "holds" the stretch isometrically. The "push" that is causing the isometric hold should be resisted against by engaging the muscle in question. The hold is held isometrically for 6 seconds and then relaxes. The last passive stretch is then held for 30 seconds and should be of greater magnitude due to the "autogenic inhibition" caused by the isometric active stretch.

Contract-Relax

Following the initial 10-second pre-stretch, and similar to the "hold-relax" technique, a force is applied in an attempt to stretch the muscle in question. In the hold-relax technique, the individual is instructed to not let the body part move and simply hold the muscle isometrically while resisting the force. In the contract-relax technique, however, the individual should actually complete range of motion, concentric contraction and then relax. A passive stretch of greater magnitude can then be performed for 30 seconds.

Hold-Relax with Agonist Contraction

This technique is performed exactly the same as the hold-relax technique in the first 2 phases, except in the 3rd phase, not only is the muscle in question being passively stretched, but there is an agonist contraction. For example, if the hamstrings were being stretched, then during phase 3, the quadriceps would contract to further accentuate the passive stretch.