Which Type of Stretching Works Best?
This blog post was first sent to Jenni’s email list as an email newsletter. Sign up for the JRY email newsletter here!
There are many styles of stretching and flexibility training – which one is the best?
This is a question many of us yoga and movement geeks often ponder. 🤓
Stretching is an integral component of all styles of yoga practice. But if we understand which types of stretching work best, this may better inform our choices in our own yoga practice or teaching!
Before we look at some recent scientific research on this topic, let's quickly review what the different types of stretching are.
The Different Types of Stretching: Static, Dynamic, PNF
Static Stretching
First of all, we have static stretching (a.k.a. passive stretching), in which we come into a stretch and hold the position for a sustained amount of time.
An example is the yoga pose ardha hanumanasana (half split), in which we statically stretch the hamstring muscles of the front leg:
Dynamic Stretching
Next, we have dynamic stretching, in which we move in and out of a stretch repeatedly in a controlled manner.
(There's also ballistic stretching, which is a higher-velocity version of dynamic stretching, and in the research we're looking at today, the researchers combined these two into one category.)
For our dynamic stretching visual example, here's ardha hanumanasana again, but this time, we bend and straighten the front knee repeatedly, moving in and out of the hamstring stretch:
PNF Stretching
Lastly, we have PNF stretching. PNF stands for proprioceptive neuromuscular facilitation. (It's a bit of a mouthful! If you know this term, you're a true yoga body geek. 🤓)
There are a few different variations of PNF stretching, but the gist is that we come into a stretch and actively contract the target muscle and/or the antagonist muscle.
In a yoga class setting, an example of a PNF-type stretch might be holding ardha hanumanasana, but digging our front heel down into the floor. This would isometrically activate the hamstring muscles (the "target" muscles) in a stretched position:
So... which type of stretching works best?
Before we answer that question, let's clarify what we mean by “works best.”
Our outcome measure of interest here is range of motion (ROM). We're specifically wondering which type of stretching results in the largest increases in ROM in the long term.
This is important to clarify because there are other outcome measures one might be interested in with regard to stretching – such as stress reduction, athletic performance, pain reduction, vascular health, etc.
But the research we're looking at today was specifically investigating stretching's effect on ROM. Got it?? :)
What did this stretching research find?
A recent systematic review and meta-analysis investigated this question, and it found that (drumroll please 🥁)…
*Static stretching* and *PNF stretching* resulted in the largest ROM increases in the long term!
Static stretching and PNF stretching were similar in their effectiveness, and they outperformed dynamic stretching.
This is just the quick-and-dirty summary of these findings for our purposes here. For a more in-depth look at this topic, I recommend reading the full paper! Here's the reference:
Why would static and PNF stretching outperform dynamic stretching?
We don’t actually know the answer to this question (!) – this research can't tell us that.
However, the researchers did speculate that one possible factor could be the difference in "time under tension" in the stretched position:
“While during PNF or static stretching, the joint is mainly in a stretched position throughout the whole stretching protocol, this is not the case during ballistic or dynamic stretching due to the swinging or bouncing movements.”
What does all this mean for us in our actual yoga practice and teaching?
The researchers suggest that when one's goal is to maximize ROM increases over the long term (i.e. to optimize flexibility training), static and PNF are the preferred stretching types.
This does not mean that dynamic stretching is a useless practice that should be abandoned, though – not at all! Remember, there are many possible goals when it comes to stretching, and ROM gains are only one.
Besides, dynamic stretching does increase ROM, just not as effectively as static and PNF stretching do.
Additionally, the researchers suggest that when it comes to a warm-up with the goal of maximizing performance, dynamic stretching is actually preferred compared to the other styles of stretching!
So dynamic stretching clearly still has its place.
But now that we have a better sense of what the research suggests about stretching types and ROM, we can make more informed decisions in our yoga practice and teaching!