Stretching Before Exercising Weakens Muscles 339
Khemisty writes "Back in grade school you were probably taught the importance of warm-up exercises, and it's likely you've continued with pretty much the same routine ever since. Science, however, has moved on. Researchers now believe that some of the more entrenched elements of many athletes' warm-up regimens are not only a waste of time but are actually bad for you. The old presumption that holding a stretch for 20 to 30 seconds — known as static stretching — primes muscles for a workout is dead wrong. It actually weakens them. In a recent study conducted at the University of Nevada, athletes generated less force from their leg muscles after static stretching than they did after not stretching at all. Other studies have found that this stretching decreases muscle strength by as much as 30 percent. Also, stretching one leg's muscles can reduce strength in the other leg as well, probably because the central nervous system rebels against the movements."
Re:Importance of warm-up (Score:2, Interesting)
Agreed. I have had too many injuries to not stretch. I believe the point is to make your muscles and tendons a bit longer, so that when they're under stress (like during a sprint), it's more difficult to stretch them to the point of tearing. Of course having stretched out muscles means that there's a little more slack, and they won't respond as well. Just guessing, though.
Somebody I knew ran track for a division 3 college, and their coach wouldn't allow them to stretch. I still find that very strange.
Re:Performance vs. Health (Score:5, Interesting)
The "stretching reduces injury" canard has been disproven in study after study. Warming up may have some benefit, but stretching isn't the way to go if you're worried about injuries.
One study is at http://www.sportsinjurybulletin.com/archive/stretching-exercises.html [sportsinjurybulletin.com]
As it turned out, stretching during warm-up had no statistically significant effect on the risk of injury, either for soft-tissue problems or bony disorders...Although pre-exercise stretching was totally unimportant from an injury standpoint, other easy-to-determine factors actually did a decent job of prognosticating who would get hurt. For example, age was a good predictor of injury (the older the athlete, the higher the injury frequency)...In addition, 20-metre shuttle-run time was an outstanding predictor (the faster the time, the lower the risk of injury), a relationship which suggested that overall fitness -- not the presence or absence of pre-workout stretching -- had the paramount influence on injury occurrence
This is old, old news. (Score:4, Interesting)
The deleterious effect of static stretching on muscle power has been known for years.
It's not a matter of static stretching being "bad for you", what's "bad for you" depends on context. Static stretching is a developmental exercise. You wouldn't go to the weight room for serious strength training before a competition, and the same applies to static stretching.
Well coached athletes have been doing the kind of warm-up exercises described in the article for years, it's just that the word hasn't trickled down.
Seems like a perfectly sensible article to me (Score:3, Interesting)
When it comes to doing martial arts classes and other exercises, I typically start with some deep breathing for 1-3 mins (preferably while walking to the class), then follow with a light 50-60% warm up. I have stretched cold before exercise in the past, but it kept causing injuries (I obviously stopped doing that). Then after I finish a class I'll cool down with some stretches while my muscles are warm - which I find I can stretch much further.
I'm over 30 now and have recently re-started capoeira (so pretty hard for work me), and these high effort classes are getting much harder since I've been out of training for a few years. Getting back in to it I've found (casual observation, no science here ;-) that after a combination of a deep breathing and a light warm up, my ability to train is increased substantially. I'm not exaggerating at all. We're talking the difference between having to stop constantly and feeling like passing out, and carrying on a class just at the edge of my comfort zone. Most of the article seems to back this experience up with some science, which I'm glad about :-)
Re:Importance of warm-up (Score:5, Interesting)
As a battered ex-goalie (Score:2, Interesting)
I used to have a daily (static) stretch routine that has lapsed since I hung up my skates, so I'm looking at this article with interest and trying to match them against my own observations and routine:
1. The purpose of the stretching routine was to allow the muscles to lengthen and reduce the chance of injury that wild flailing contortions on a slippery surface exposes you to.
TFA suggests that muscles are "weakened" (in terms of performance) but does not say that those muscles have been exposed to injury risk. Also, the parts of my body I'm protecting are the non-stretchy bits of ligament and tendon that may see too much load if muscles are too tight.
2. The routine was a set of systematic, static stretches held for a minimum of 30 seconds. But the whole set was always, always, always preceded by a light warmup: jogging, a few pushups, etc.
This is borne out by the article, which said (surprise!) that warmed up muscles work better. In fact, cold muscles are just hard to stretch, and you risk injuring yourself right there.
Dynamic stretching was something I was aware of at the time, but it came with a bit of a warning-- if you don't know what you're doing with exercises that stretch muscles that are under tension, or you're not in peak physical shape, you can hurt yourself pretty fast.
It does sound like there's been progress in this area... it was very hard to find information on "how to do effective dynamic stretching without breaking yourself" five years ago.
Now... as for the "ex" part of "ex-goalie": my first knee injury was an MCL tear on a game in early summer, when I wasn't in a regular stretch routine, when I hadn't followed my regimen properly before game. That emphasizes to me that not following a stretching routine was infinitely worse than a static stretching routine. I won't comment on whether what I did do was optimal-- I suspect it could have been improved.
(FWIW it wouldn't have saved me from knee injuries #2 and #3, patella subluxations that put me out of the sport for good. Turns out I have shallow trochlear grooves [athleticadvisor.com] and sliding kneecaps are bad if you like butterfly goaltending and dislike obscene amounts of pain.)
So best I can say is that this article's pretty inconclusive about whether static stretching is actually bad. I believe that even if it cuts your muscle output, it's still having an effect in increasing your safe range of motion, and both (a) better than no stretching and (b) more easily managed for an amateur than some potentially aggressive dynamic stretching approaches.
Breathing causes cancer Re:Importance of warm-up (Score:3, Interesting)
Actually, yeah, oxygen causes cancer.
There's a graph of incidence of cancer against oxygen concentration. As you increase the oxygen percentage of the air, the rate of cancer goes up, and if you reduce it, it goes down. If you reduce it too far, you die.
However, if you plot the curve back to the 0% oxygen axis you find that there's a certain amount of cancer still there- that's the cancer due to other causes than oxygen.
But there's a gap- some of the cancer that you get due to the normal oxygen levels you need to live raises the cancer rate measurably.
So, it looks like oxygen causes cancer, and hence so does breathing!!!
Re:Importance of warm-up (Score:2, Interesting)
I agree with Eskimo. I'm also a martial artist (BJJ instructor), and we only do dynamic stretches before practice or sparring as well. Instead we begin with a light warm-up to (duh!) warm up the muscles. Then we train sport-specific movements as well as dynamic stretches to build muscle memory and increase flexibility. After practice we might finish with some yoga, but we got rid of the generic static stretches with no problems. Our Muay Thai instructors do the same thing at their practices. As far as I knew, the thesis of this article was common knowledge in the sports world for a while now. It has made us more flexible and faster with less occurring of injuries than when I was doing static stretches. We have some really good fighters and competitors, so I don't doubt our training methods. They seem to be working for us.