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Stretching Before Exercising Weakens Muscles
Posted by
kdawson
on Fri Nov 07, 2008 09:40 AM
from the everything-you-know-is-wrong dept.
from the everything-you-know-is-wrong dept.
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."
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Importance of warm-up (Score:5, Informative)
Back in the days when i was in school, warm-ups were there to avoid injuries, not to increase your performance.
By making your muscles weaker, the chance to get an injury decreases as well. People have proved over time (and quite many times) that you are able to hurt yourself with the strength of your muscles alone (ever seen those 100m sprinters falling like bricks on half way ?).
Re:Importance of warm-up (Score:5, Insightful)
It's like most things in that too much of even a good thing can be bad for you. It's very important to limber up before a workout, but anything can be taken to extremes.
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Re:Importance of warm-up (Score:5, Insightful)
That was my thought. 20 - 30 seconds is far too long to hold a stretch before exercise. A warm up should be just that - moderate activity to get the muscles ready for your workout.
When I run, I start with a brisk five minute walk, followed by some easy stretching before I begin my run, but I won't hold a stretch for more than ten seconds. You can also just stretch as you do your warm up, by walking on your toes, kicking your butt, and basically walking like you're applying for a government grant.
The 30 second stretches are for after your workout, during the "cooling off" period.
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Re:Importance of warm-up (Score:4, Insightful)
I think this entire article is a load of attention seeking BS, and I will not believe a word of it until I see a proper peer-reviewed research paper in a medical journal that debunks stretching.
While I'm sure that it is possible to overstretch a muscle, especially if you isolate one muscle and use all your opposing musculature to stretch it excessively, the implied message of this article is rubbish. There is absolutely no evidence that stretching before exercise weakens muscles (note I used the exact same phrase as the title) so long as you don't over do it.
In other news:
Breathing is bad for you!
Hyperventilating can result in a situation where you remove too much CO2 from your bloodstream leading to a failure of the breathing reflex, resulting in hypoxia and in extreme cases brain damage or death).
Exercise is bad for you!
Bodily ligaments and tendons wear out, just like any other mechanical part, so the more you use them the faster they wear out. The body does have a regenerative effect, but it is not unlimited and the deterioration of the body's ability to maintain joins manifests in arthritis and other related conditions.
Water is bad for you!
You can drown.
These articles brought to you by the Department of Attention Whores with no Sense of Truth or Accuracy.
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Re:Importance of warm-up (Score:5, Informative)
Increasing flexibility is for after the workout, where you hold a stretch for 20-30 seconds (for muscle memory).
Maybe I have drank too much of the koolaid, but I assume this is what the article is talking about. It's been around for a while (at least 8 years).
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Re:Importance of warm-up (Score:4, Insightful)
It's been around for a while (at least 8 years).
Try 30+ years
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Re: (Score:3, Funny)
what an awful acronym.
Re:Importance of warm-up (Score:5, Informative)
I think this entire article is a load of attention seeking BS, and I will not believe a word of it until I see a proper peer-reviewed research paper in a medical journal that debunks stretching.
How about these:
Nelson AG, Kokkonen J, Arnall DA: Acute muscle stretching inhibits muscle strength endurance performance. J Strength Cond Res. 2005 May;19(2):338-43
Power K, Behm D, Cahill F, Carroll M, Young W: An acute bout of static stretching: effects on force and jumping performance. Med Sci Sports Exerc.2004 Aug;36(8):1389-96
Cramer JT, Housh TJ, Weir JP, Johnson GO, Coburn JW, Beck TW: The acute effects of static stretching on peak torque, mean power output, electromyography, and mechanomyography. Eur J Appl Physiol. 2005 Mar;93(5-6):530-9. Epub 2004 Dec 15
Fletcher IM, Jones B: The effect of different warm-up stretch protocols on 20 meter sprint performance in trained rugby union players. J Strength Cond Res. 2004 Nov;18(4):885-8
This is not exactly news. The studies have been showing these same results for years now.
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Re:Importance of warm-up (Score:4, Insightful)
The word "acute" in the title of 3 out of 4 of those papers highlights that what I was saying, i.e., it is not stretching but over stretching that is bad for you. I don't think these papers would suggest that a rugby player get to the field and get into the scrum 20 minutes after getting out of bed and with no preceding activity.
Well done, it's not often that someone can actually cite references to prove that they missed the point.
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Re:Importance of warm-up (Score:5, Informative)
Actually, when they talk about the acute effects of stretching, they're talking about the immediate effects.
That is, weakened muscles are an acute effect because the effect only lasts ~30 minutes. Acute does not mean they stretched the bajeezus out of a muscle before the test.
Furthermore, you still seem to be having trouble grasping the difference between stretching, static stretching, and warming up.
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Re:Importance of warm-up (Score:5, Informative)
There is absolutely no evidence that stretching before exercise weakens muscles (note I used the exact same phrase as the title) so long as you don't over do it.
if you haven't actually read any peer-reviewed articles about it?! You do know about scholar.google.com, right? It's not that hard to check on the people interviewed in the NYTimes article. There are many papers on the subject. Yes, there is still work to be done to answer all the questions, but your ridiculous statement that there is absolutely no evidence that stretching (static) before exercise weakens muscles just shows that you haven't bothered to read about it.
Here's your spoon-fed google search with links to a few abstracts for your edification.
http://www.acsm-msse.org/pt/re/msse/abstract.00005768-200403000-00004.htm;jsessionid=JJgJGzgYVCy4qyLKzfW21kXYSGvYP3tWmM2WDyC6Nr1nvvvH7ykd!-1853705402!181195629!8091!-1 [acsm-msse.org]
http://eric.ed.gov/ERICWebPortal/contentdelivery/servlet/ERICServlet?accno=ED448119 [ed.gov] [PDF]
http://www.ncbi.nlm.nih.gov/pubmed/9368275 [nih.gov]
http://www.bmj.com/cgi/content/abridged/325/7362/468 [bmj.com]
http://www3.interscience.wiley.com/journal/119251161/abstract?CRETRY=1&SRETRY=0 [wiley.com]
http://www.cjsportsmed.com/pt/re/cjsm/abstract.00042752-200409000-00004.htm;jsessionid=JJgpcrQvSRyyCn1CG2XnW4WS6vzdsmrXnhG43kmLDT1CyhhCknr9!1600976923!181195628!8091!-1 [cjsportsmed.com]
http://apt.allenpress.com/perlserv/?request=get-abstract&doi=10.1519%2F1533-4287(2001)015%5B0098%3AAEOSAN%5D2.0.CO%3B2 [allenpress.com]
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Re: (Score:3, Insightful)
There are many papers on the subject. Yes, there is still work to be done to answer all the questions, but your ridiculous statement that there is absolutely no evidence that stretching (static) before exercise weakens muscles just shows that you haven't bothered to read about it.
There's a really subtle point that a lot of this work seems to overlook. Muscles are length dependent force generators, meaning that they'll produce more force at longer lengths. One of the things that happens during a prolonged static stretch is that the tendons creep a little, meaning that, at the same joint position, the muscle itself is at a shorter length. If you measure force, stretch, then measure force again at the same joint configuration, you're not measuring the muscle in the same configuratio
Re: (Score:3, Insightful)
I've always thought about it in terms of steel cables and rubber bands.
If I tie one end of a steel cable to a load that is stuck in the mud and the other end to the back of my truck, and leave it slack, and floor my truck, I'm going to get more snapping power to dislodge the load, but I'm at higher risk of breaking the cable.
If I tie one end of a bungee cord to a load that is stuck in the mud and the other end to the back of my truck, and leave it slack, and floor my truck, the elongation is going to sap a
Re: (Score:3, Informative)
There's a bunch of energy stored in the snatch-strap, which wants to go back to its original shape. It eventually does return to
Re: (Score:3, Informative)
You are wrong. A number of studies show that stretching when cold is not a good idea. As the article stated, stretching is good, AFTER, a light warm up like an easy jog for 5 to 10 minutes. Stretching when cold does not help prevent injury, and does not improve athletic performance. You should not do intense stretching before playing sports. If you need to improve flexibility do the stretching as a separate exercise on your work out days.
Stretch after warm up. [mydr.com.au]
Stretch after your work-out, Athletes who s [bodybuilding.com]
I've got your peer-reiviewed papers right here (Score:5, Informative)
I think this entire article is a load of attention seeking BS, and I will not believe a word of it until I see a proper peer-reviewed research paper in a medical journal that debunks stretching.
Geeze. I've noticed a certain hyper-skepticism among Slashdotters. Please note that the New York Times is not known for trumping up pseudoscience with no support in the literature.
Others have responded that the article is not "debunking stretching", just pointing out problems with certain kinds of stretching. And at least one other poster gave references, some of whom involved people interviewed for TFA. More specifically with respect to the studies mentioned in TFA:
The article cites Duane Knudson, a kinesiology professor at CSU. Peer reviewed research paper [springerlink.com].
The article mentions a Las Vegas stretching study. Peer reviewed research paper [allenpress.com].
The article mentions Malachy McHugh, a researcher in NYC. Peer reviewed research paper [acsm-msse.org].
The article mentions a collegiate volleyball study. Peer reviewed research paper [acsm-msse.org].
And so on.
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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 n
Re: (Score:3, Informative)
In weight lifting you do not want to stretch your muscles out. In anything more aerobic you want to do light stretching and at the end of both you want to completely stretch your muscles.
Your muscles are able to put forth the most when they are not all stretched out similar to an elastic band. If you stretch it out several times it starts to lose its ability to snap back as quickly. For aerobic exercise though you don't want your muscles to cramp up which they have an increased chance of doing because of th
Re:Importance of warm-up (Score:5, Informative)
That may be adequate for running, but it won't do for regimens with extreme range of motion, such as martial arts. We stretch for half an hour prior to a workout punctuated with short one-minute warm-ups every five minutes or so, and it definitely reduces injuries (which, as the GP has it, is the intent... not for "strength"... in fact, I've never heard — anywhere — that the act of stretching increases strength for the immediately succeeding session of exercise. I've been teaching martial arts for over twenty years.)
I can also tell you that if your body isn't prepared to reach an extended position, and it has to go there, either because you forced it to or someone else did, you had better have stretched first and be warmed up.
As for this line in TFS: "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", the science of this has been known for many years. What happens is that the working elements of the muscle fibers are laid against each other in pairs with an intervening layer between; the more overlap, the more power can be generated because the overlapping surface area of the layer between is where the work gets done. When fibers are stretched, there is less overlap, hence the muscle can generate less power, but the muscle is longer.
Think of your forearm extended, and look at your bicep... see how it is long? Lots of fiber layers have slid against each other and now have considerably less overlap. Now move your arm to the 90 degree position at the elbow, and look at your bicep; it's bunched up, even if it isn't tense: many fiber layers are now slid to an overlapping position.
The number of fibers involved is the factor that determines the total amount of strength in your motion; high recruitment of fibers results in a strong motion, low recruitment results in a weak motion. We train to develop the ability to generate high recruitment on demand. But no matter the recruitment, if you start from a highly non-overlapped position, eg a stretched one, you'll generate less power with the stretched muscle.
This is the basis for moves like arm locks; if the arm is extended, not only is the leverage at the joint reduced, making it more difficult to close the arm against the lock, but the muscle is extended by the lock so that fiber overlap is minimal, which reduces the amount of force that can be generated by the muscle — it is literally a "double-whammy", and accounts for why a fully executed lock is so hard to exit using direct force (correct exits involve rotation of the arm or the lock itself in order to effect closure of the joint, and a good lock prevents such rotation.)
For any motion, you typically will have two muscle groups involved; the agonist, which is the muscle doing the work, and an antagonist, which is the muscle that would be responsible to reverse the motion. In the case of bending at the elbow, to close the arm, the bicep is the agonist and the triceps is the antagonist. If you are trying to open your arm, that is, extend your forearm, then the roles are reversed: The triceps is the agonist and the bicep is the antagonist. One of the key elements of controlling the force your body can generate is learning to really relax the antagonist, and again, stretching helps by teaching you what a really relaxed and extended muscle feels like; it is difficult to minimize fiber recruitment if you don't know what it feels like and the muscle isn't accustomed to that condition.
Anyway, my recommendation is that athletes ignore this report entirely; stretching significantly increases your range of motion, particularly in your ankles, legs, groin, waist, wrists, fingers, back, neck and shoulders, and to the degree that your sport requires (or risks) large range o
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Re:Importance of warm-up (Score:5, Interesting)
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Re: (Score:2, Informative)
Back in the days when i was in school, warm-ups were there to avoid injuries, not to increase your performance.
By making your muscles weaker, the chance to get an injury decreases as well. People have proved over time (and quite many times) that you are able to hurt yourself with the strength of your muscles alone (ever seen those 100m sprinters falling like bricks on half way ?).
From the article:
THE RIGHT WARM-UP should do two things: loosen muscles and tendons to increase the range of motion of various joints, and literally warm up the body. When youâ(TM)re at rest, thereâ(TM)s less blood flow to muscles and tendons, and they stiffen. âoeYou need to make tissues and tendons compliant before beginning exercise,â Knudson says.
Re:Importance of warm-up (Score:4, Insightful)
That's exactly what I thought when I read the summary. That it can reduce strength is news to me, but I always thought the importance of it was to prevent injury. And given this is a tech site, I don't see why it matters to most of the people here. Hell, most of us probably don't get enough exercise to begin with, let alone taking it to the level where performance matters.
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Re:Importance of warm-up (Score:4, Insightful)
Can we please cut it out with the everybody-interested-in-technology-is-a-fat-slob jokes? And the everybody-interested-in-technology-is-socially-inept-and-has-no-luck-with-the-opposite-gender jokes? Seriously, it's getting old.
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Re: (Score:3, Funny)
Can we please cut it out with the everybody-interested-in-technology-is-a-fat-slob jokes? And the everybody-interested-in-technology-is-socially-inept-and-has-no-luck-with-the-opposite-gender jokes? Seriously, it's getting old.
Yeah not everybody here is like me.
I'm special!
Re:Importance of warm-up (Score:5, Funny)
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Re:Importance of warm-up (Score:5, Insightful)
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Re: (Score:3, Funny)
You must be new here.
Welcome to /., where everybody needs to get laid.
Re:Importance of warm-up (Score:5, Funny)
Sounds like someone needs to get laid.
Just don't stretch first.
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Re: (Score:3, Insightful)
Sure, we'll stop right after we stop the jokes about lawyers being unethical, plumbers showing way too much buttcrack, politicians lying, and sharks wearing frickin' lasers. (OK, that last one may not fit in)
Please RTFA (Score:5, Informative)
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Muscle Cramps? (Score:5, Insightful)
Also when I lift, I would rather be a little weaker than having my arm freeze up as I lift a barbell over my head.
I don't think I ever had the impression that stretching makes me stronger, just protects me from cramps and overextending. Has this been proven/disproven? I'd be shocked to see so many years of sports medicine overturned by something that could be easily determined through statistics acquired by anyone working out.
Re: (Score:3, Informative)
Absolutely agree with everything you've posted - I was going to say the same thing. To add to that though, this isn't new at all. My exercise book from 2-3 years ago has exactly the same information - stretching will reduce performance, but it's still worth it.
Not the real purpose of stretching??? (Score:2)
I always thought that other reasons for stretching include getting your heart rate up and getting more oxygenated blood throughout your body (so that, even though you can get more strength by not stretching, your heart isn't burdened unnecessarily). It's not so much for your muscles as it is for other parts of your body needed for the activity.
Warm-up still important (Score:5, Insightful)
For those of you who don't RTFA, the summary could be misleading. TFA doesn't imply it's best to just jump straight into exercising. Rather you still need to do some warm-up activity (light jogging, jumping jacks, etc..), and then do dynamic stretches, rather than static stretches. What dynamic stretches you should do depends on your sport.
Furthermore, since this is slashdot, you all probably have terrible posture stemming from over-tight hip-flexors and internally rotated shoulders. Static stretching can be good to loosen the problem muscles. People who bother to stretch usually focus way to much on the hamstrings, when the hip flexors are much more likely to be the problem.
Re: (Score:3, Informative)
1) You want to stretch ONLY muscle, rarely tendon (muscle to bone connections), and NEVER ligament (holds bones together). Think of a mechanical coupling such as ball joints in a car (yes! a car analogy!.:-) ) If they are tight, forces are transmitted as they should be. Loose couplings - not only do your teeth get rattled, but parts tend to wear out.
Back to the meat worl
Depends on your sport (Score:5, Informative)
Based on what I've read, stretching/warm-up should be based on your sport.
For instance, I coach a hockey team, and any stretching is considered bad, as it loosens the tendons, and you are now more prone to injury because "things" can move too far...
We (the team) do simple warm-ups.
Note to self: read linked articles before posting! (Score:5, Informative)
Some types of stretching are good, some are bad. The article explains the differences quite well and still recommends that some stretching takes place...
...Revolution! (Score:3, Funny)
I'm a huge fan of the Dance Dance Revolution games. I've ranked highly in both tournaments that I was able to participate in.
One thing that I've noticed over time is that I usually play better on the second and third songs of my first set than I do for the rest of the night. I don't know if this is related to fatigue (the total lack thereof for the first few songs) or if the so-called muscle stiffness makes the actions more deliberate (and perhaps more precise as a result).
That said, if I'm going to play the most difficult songs (MaXXes, PSMO, etc) then I definitely need a good warmup. This almost never involves stretching.
20-30 sec? (Score:3, Informative)
Where did that come from? I've been taught since being a 6 year old hockey master that you should always do warm up, and then stretch max 10 seconds per muscle...
Right after exercise, you shouldn't stretch as your muscles should be full of blood, you don't want to rip them open – you should walk or do something light and go to sauna.
2-3 hrs after exercise you should do those 20-40 sec stretches.
MOD Parent UP (Score:3, Insightful)
The 20
Not new information. (Score:4, Informative)
Re:Not new information. (Score:4, Funny)
...pickup some kettlebells from the site. Mine are worth their weight in gold.
Wow! At today's gold price, that's $425,231 for a 35lb kettlebell. I value my physique, but I would have to think twice about that...
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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.
Public Education Conspiracy (Score:3, Funny)
bad assumption (Score:3, Insightful)
static stretching is not for warming up before athletic performance - it is for increasing flexibility. Of course it would result in weaker muscle output - the goal of that kind of stretch is to slightly pull the muscle - similar in effect to muscle-tearing during a heavy weights workout - the torn/stretched muscle then should be given the opportunity to heal in it's new configuration.
Again, it's not supposed to generate more muscle power.
To properly warm up for a game or athletic performance, you want to stretch some but mostly do repetitive movement. Start small and build up to wider movements. Also for raw power, don't discount heart rate and oxygen uptake - being "up to speed" on heart is in many situations more important than warm muscles.
Missing the point entirely... (Score:4, Funny)
I think the author of this article has completely missed the point of stretching. It has absolutely nothing whatsoever to do with increasing or decreasing your overall muscle strength. Additionally it has nothing to do with preventing injury or warming up either. In actuality stretching for humans is the same thing as frogs inflating their bellys. It is solely to attract the opposite sex.
Study after study has proven than men who stretch their forarms (also known as guns) in front of women have a greater likelyhood of mating. It's a known fact also that women who do yoga are more likely to excel in the reproductive arts.
A more interesting study would be the effect of biker shorts on your ability to determine potential danger (such as a speeding car) or how fanny packs have led to retardation and uneven hair growth (re. the mullet)
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: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
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Re:Performance vs. Health (Score:4, Informative)
Stretching might be bad for performance, but it does reduce injury.
From TFA:
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Re: (Score:3, Funny)