Stretching Demystified

Flexibility is an important aspect of fitness, along with muscular strength and endurance, and aerobic capacity.   However, it is not uncommon to find athletes who are unable to bend over and touch their toes!  This is most likely due to sitting most hours of the day and attempting to reverse the changes by ten minutes of stretching at the gym.

In the past decade, there has been much discrepancy in recommendations about stretching: how long, what kind, which muscles?  Does it depend on your sport of choice? Before or after a workout?

There have been countless studies published, even in the past year, with varying results. However, they all agree on one thing: Do not perform static stretches prior to exercising.

WHY NOT?

Static stretching alters the (microscopic) length of the muscle which can alter, and likely decrease, its firing potential.  Stretching may also activate tendon structures that inhibit muscle action.  Both of these proposed mechanisms will decrease power output.

“Then how should I warm up?”

Warm-ups are essential to performance and injury prevention.  They are useful for increasing the core temperature to decrease stiffness of muscles and alerting the neurologic system to the events about to take place.  This should be achieved with specific, dynamic exercises rather than static stretches or laying on the foam roller.

Runners—Studies found that a dynamic warm-up increased performance of endurance runners, meaning they ran longer without exhaustion1.  This warm-up consisted of movements such as high knees, butt kicks, leg swings and hopping.  Total time: 4 minutes.

Notice, I said nothing about running.  Those athletes warming up with running had comparable results to those not warming up at all. Check out Dr. Danny’s post specifically addressing running warm-ups.

Weightlifters—Other studies found that just ONE set of static stretches decreased 1RM performance by 5.4%2.  That would decrease your 400 lb back squat by 21.6 lb!

When performing sets for reps, static or ballistic stretching decreased amount of reps by 17-20%3. That’s 2 less reps in your 10 rep set.  The most effective was a specific warm-up of 20 reps around 30% 1RM, then appropriately building to working weight.

For Olympic Lifts, additional dynamic warm-ups may be warranted, specifically for the overhead movements. One of my favorite drills is thoracic rotation4, performed in between light warm-up sets:

CrossFitters—You fall somewhere in between; Choose your warm-up type based on the workout of the day.  The same theme holds true: specific, dynamic warm-ups!

Sport-Specific Athletes—Dynamic, sport specific warm-ups are the most effective to prepare for practice or competition.  This includes running, cutting, jumping, ball handling, throwing or whatever your sport demands.  Begin at a slower pace and then work up to competition speed movements.

Your workout is over, you ran your fastest 5K, PRed your back squat or scored the winning goal... NOW you stretch. 
​
To address the earlier question: When, how long, what kind, which muscles?
To receive any benefit, hold static stretches for at least 30 seconds but 2 minutes may show better results. Static stretches can work but they take a few weeks for sustainable differences.  
PNF (proprioceptive neuromuscular facilitation) stretches have been shown to be superior to static stretching.  These can be done with a buddy or by yourself using bands or straps.  A common form of PNF to increase range of motion is contract-relax.  You have likely seen it before:

• Bring muscle to limit or restriction
• Increase tension in muscle by contracting maximally but counteracting movement with the strap
• Relax muscle and gain a few more degrees of motion

So on the hamstrings, it looks like this5:

​This would also be the appropriate time to work with the foam roller or PVC pipe on the muscles that are sore or may be lacking flexibility.

Of course, the cartoon at the top is wrong.  Touching your toes IS everything.  Every athlete should have the flexibility to bend over and touch their toes whether or not they are warmed up.  Inefficient muscle length can lead to compensation by other muscles.  This causes joint pain, tendonitis, faulty movement patterns, poor form and then decreased performance or injury. Stretching is also great to incorporate into rest days. A light warm-up, then your favorite stretches or maybe your least favorite if you have some restrictions.

Self-management is 100% possible when it comes to flexibility and recovery!  Take the time to take care of your body and it will perform better. Remember, at Athletes’ Potential you can supplement your stretching and take recovery to the next level with full-body cryotherapy and NormaTec compression boots. Call us anytime to schedule an appointment!


Thanks for reading,

     Dr. Jackie, PT, DPT, CSCS



References

1. Yamaguchi, T, Takizawa, K, and Shibata, K. Acute effect of dynamic stretching on endurance running performance in well-trained male runners. J Strength Cond Res 29(11): 3045–3052, 2015.
2. Winchester JB, Nelson AG, Kokkonen J. A single 30-s stretch is sufficient to inhibit maximal voluntary strength. Res Q Exerc Sport, 2009; 80: 257-261.
3. Barroso R, Tricoli V, Dos Santos Gil S, Ugrinowitsch C, Roschel H. Maximal strength, number of repetitions, and total volume are differently affected by static-, ballistic-, and proprioceptive neuromuscular facilitation stretching. J Strength Cond Res, 2012; 26: 2432-2437.
4. https://v1.voltathletics.com/node/879
5. https://www.cooperinstitute.org/2014/03/self-pnf-stretching-better-than-static-stretching/