I could talk about this for days. But instead, I decided to write a shorter article.
Here I’ll discuss the pros, cons, and myths of stretching.
Then I’ll give a brief description of how it works, so you can start to make sense of it all.
And finally, a question for you to think about whenever you are deciding how you should (or shouldn’t) include stretching in your lifestyle.
Turns out it’s not so simple.
- Pros, Cons, and Myths
- ‘Pros’ of stretching.
- Myths: What it doesn’t do.
- ‘Cons’ of stretching.
- How Stretching Works.
- Personal note.
- Should you stretch?
- How flexible do you need to be?
- So how can you prevent injuries?
- General Recommendations.
Stretching is any activity intended to improve your range of motion (flexibility). There are tons of types, but I won’t get into that here. When most people think of stretching, though, they think of ‘static’ stretching, where you stretch your muscle to its end point, perhaps putting a little more pressure on it, and then hold it for some amount of time.
So, why would you do this?
- Stretching seems to feel good, as long as you don’t go too crazy with it. One possible reason why it does this will be explained below (how stretching works).
- Stretching may help with sports that require above normal flexibility 2, like dancing, gymnastics, or diving.
Now for the bad news… ‘static’ stretching doesn’t do what we once thought it did!
- Stretching actually does not decrease your risk of overall injuries 4, 5, 6, especially overuse injuries, or anything other than a muscle strain 7. This should make sense when you think about how injuries actually happen.
- Stretching does not decrease muscle soreness 8. It might feel like it do at the time, but it don’t last. It feels good at the moment, and lasts an hour or two, but it’s not great for that next couple day exercise soreness. You’ll see why below.
CONS: Yup, cons! Stretching can actually have cons.
- Stretching more than 45 seconds has been shown to decrease muscular strength (by about 5%), power (~2%), and explosive performance (~2%) for up to an hour. The longer the stretch, the greater the weakness 11. So be sure to keep the stretching short and sweet before athletic pursuits!
Woah! So stretching isn’t all it’s cracked up to be! Why is that?
None of this means stretching “don’t work”, or that you “shouldn’t stretch”. After all, review the ‘pros’! It does have benefits. However, people need to be aware of the limitations of stretching. Only then can you implement stretching into your training regimen properly.
How Stretching Works
It seems stretching has its effect on your nervous system… but doesn’t really make your muscles longer or ‘stretchier’.
In 2010, an article in the journal physical therapy reviewed research on the basic science of stretching 12. After deconstructing many popular theories of what happens when you stretch, the authors made the following conclusions:
The idea that stretching actually increases muscle extensibility (stretchiness) is not substantiated by any good scientific research, and neither is the idea that it literally lengthens muscles.
Currently, the best theory is that stretching increases your ‘stretch tolerance’, either by decreasing the pain threshold, and/or decreasing the muscles resistance to stretching. It does the latter by temporarily altering the receptors in your muscles, tendons, and ligaments that usually react to stretching by making your muscles tighten up. There are a lot of possible mechanisms, and we don’t quite understand it all yet.
This change in the nervous system probably explains why it seems to feel good to stretch (at least during a light stretch). It decreases the feeling of tightness by increasing your tolerance.
Basically, your muscles get used to the range in which you use them. However, this effect seems to only last a couple hours… it takes weeks of consistent stretching to really increase your flexibility ‘permanently’, and if you stop stretching, it will likely go back to ‘normal’. Use it or lose it!
When I think about my clinical experience as a physical therapist, this actually makes a lot of sense.
Working in a rehabilitation hospital, I notice that people who have a complete spinal cord injury below the level of around T-10 (and often not displaying any spasticity) usually have incredible amounts of flexibility in their legs.
Of course, they can’t feel them or move them. But it is interesting to think that perhaps we all have very flexible muscles, and it’s nothing more than our nervous system that stops us from going to lengths that we are not used to.
Our nervous system says: “Woah! That’s not normal, probably not useful, and not safe!”
Confused? It’s okay, so are the researchers and scientists. All you need to worry about are the main points stated above in pros and cons.
So then, the question is:
Should you stretch?
Well, that clearly depends on your sport, your level, and your goals! For example, the goals of a weight lifter would be quite different than a dancer.
Dancers: The answer is probably yes for flexibility. But be careful. Read: Stretching for Dancers – Discussing the Research.
Strength Training: While you should probably warm-up, it seems that stretching probably isn’t a good idea (5% decrease in strength? No thanks!).
Goals should always determine your decision making.
Speaking of goals…
How flexible do you need to be?
Not everyone needs to be flexible!
If you need to open your legs wider to do some sort of movement, then perhaps you should stretch your groin regularly until you can do it. If your sport or activity requires a lot of flexibility, its probably a good idea to do some stretching before you practice or perform. It may prevent that over-stretching type muscle strain if you are in a sport where you have to kick your legs open quickly (dancing comes to mind).
However, if you don’t need to be flexible, stretching might be quite a waste of time! And even if you do need flexibility, it seems that once you have it, stretching can become a smaller part of your training program. Since it don’t seem to prevent all injuries very well, all you need is enough to maintain your flexibility.
When it comes down to it, if you don’t need to be flexible for your activity, this is probably how you should stretch:
So how can you prevent injuries?
Coordination: balance, stability, and agility training seems to be very important. See: Coordination Training.
Progression: don’t skip steps when trying to learn something, exercising, or rehabilitating an injury. Give your body time to adapt!
If you decide stretching is something you need to do (your goals require greater than normal flexibility) then here is how you can include stretching while avoiding the ‘cons’.
1. Warm-up (raise your temperature and sweat a little) and include simple, sport-specific, ‘dynamic’ stretches. ‘Static’ stretches should be limited to 15-30 second holds, once per position. Warm-up for 10-15 minutes, or until you feel ready to rock.
2. Exercise / Compete / Perform / Practice… do your thing!
3. Lots of ‘Static’ stretching afterwards to improve flexibility, if you need to. Hold sport specific positions at the end range (avoid pain) for about a minute, repeating 2-3 times.
So, should you stretch? Well, I gave you the information. Now it’s time for you to weigh the pros and cons, and decide for yourself.