Whenever I see someone stretching before or after hard exercise, I worry that the person has gotten bad advice about training.
• You should not stretch before a competition because stretching weakens muscles.
• You should not stretch after hard exercise because stretching muscles that are already damaged by intense exercise delays recovery and increases risk for injury.
• You cannot lengthen muscles or tendons by stretching.
An extensive review of the scientific literature showed that the supposed benefits of stretching are highly controversial (Int J Sports Phys Ther, 2012 Feb; 7(1): 109-119).
Stretching Does Not Lengthen Muscles
You can make a muscle longer while you are stretching, but after you finish stretching, the muscle returns to its former length. A review of 26 studies of stretching for 3-8 weeks found that stretching did not elongate muscles or tendons. The people were able to stretch further only because they learned to tolerate more pain (Scand J Med Sci Sports, Mar 2018;28(3):794-806). People who stretch regularly, such as gymnasts and people who do yoga, can stretch further than non-stretchers because they can tolerate more pain or they have less pain while they stretch (Scan j Med & Sci in Sports, Feb 2010;20(1):136-144).
Stretching a muscle pulls on nerve fibers in the muscle to cause pain, so you stop stretching when it hurts. When a person is given an anesthetic, he can stretch much further because he feels less pain. Regular stretchers stretch so often that they feel pain later than non-stretchers do and they learn to tolerate more pain when they stretch. If muscles did remain stretched, stretching would harm you because the overstretched muscle would lose its elasticity and be much weaker. Placing animals in muscle-stretching casts for several weeks can cause the muscles to grow extra units called sarcomeres, but muscles return to their original length soon after the cast is removed.
Stretching Does Not Prevent Sports Injuries
Muscles and tendons tear when the force applied to them is greater than their inherent strength, so anything that makes a muscle stronger helps to prevent injuries. Stretching does not strengthen muscles so it does not prevent injuries such as shin splints, bone stress fractures, sprains or strains (Research in Sports Medicine, Dec 2, 2016;25(1):78-90).
Stretching Does Not Prevent Delayed Onset Muscle Soreness (DOMS)
A review of 12 studies published over the last 25 years shows that stretching does not prevent delayed onset muscle soreness (DOMS), soreness that occurs eight to 24 hours after you exercise vigorously (The British Journal of Sports Medicine, December 2011; 45:15 1249-1250). Researchers in Australia reviewed five studies, involving 77 subjects, to show that stretching does not prevent next-day muscle soreness (British Medical Journal, December 2007; 325:468-70 and 451-2).
To enlarge a muscle and make it stronger, you have to put enough force on it to damage that muscle, so proper training requires some degree of muscle soreness on the day after an intense workout. Athletes train by taking a hard workout, feeling sore the next day, and then taking easy workouts for as many days as it takes for the soreness to go away. Since stretching does not reduce muscle soreness, it will not help you to recover faster from hard exercise. The best way to recover from exhausting competition is to move with little pressure on muscles, such as cycling on a stationary bicycle (American Journal of Physical Medicine & Rehabilitation, June 2007).
How Muscles Move Your Body
Every muscle in your body is made up of thousands of individual fibers. Each muscle fiber is composed of sarcomeres, repeated blocks lined up end-to-end to form rope-like fibers. Muscles move your body by contracting which shortens each muscle fiber. Muscles do not shorten (contract) equally throughout their lengths. Muscles contract only at each of thousands of sarcomeres. It is the cumulative shortening of thousands of sarcomeres that shorten fibers to make muscles contract and move your body. A sarcomere contains two proteins: actin and myosin. The actin proteins line up between myosin proteins above and below them. The actins slide toward each other to shorten the sarcomere. When thousands of sarcomeres shorten together at the same time, the entire muscle contracts.
Stretching Before Exercising Weakens Muscles
Stretching before competition and training weakens muscles. Elite college sprinters were timed in 20 meter sprints, with and without prior multiple 30-second stretches of their leg muscles. Both active and passive stretching slowed them down (Journal of Sports Science, May 2005). Stretching prevents you from lifting your heaviest weights or running your fastest miles. It limits how high you can jump, and how fast you can run (Scand J Med Sci Sports, 2013 Mar;23(2):131-48; J Strength Cond Res, 2013, Apr;27(4):973-7). Stretching weakens muscles temporarily by almost 5.5 percent.
The longer you hold the stretch, the more strength you lose. Holding a stretch for more than 90 seconds markedly reduces strength in that muscle. Stretching reduces power: how hard you can hit a baseball or tennis ball, or how fast you can swim, run or pedal. When you stretch a muscle, you pull on the muscle fibers and stretch apart each fiber at the thousands of Z lines between the sarcomeres. This damage occurs only at the Z lines throughout the length of the muscle fiber, to weaken the entire muscle. On the other hand, warming up makes muscles more pliable, helps you to run faster and lift heavier, and helps to prevent injuries.
Stretching Does Not “Warm Up” Muscles
Stretching can never be considered “warming up”. Holding a muscle contraction does not generate much heat and therefore does not warm up muscles. Warm up by starting out your exercise slowly and gradually increasing the intensity. This raises muscle temperature to make muscles more pliable and resistant to injury. Since almost 80 percent of the energy used to power muscles is lost as heat, you must contract and relax muscles continuously to generate the heat necessary to raise muscle temperature.
Warming up before you exercise helps to prevent injuries and lets you jump higher, run faster, lift heavier or throw further. Your warm-up should involve the same muscles and motions you plan to use in your sport. For example, before you start to run very fast, do a series of runs of gradually-increasing intensity to increase the circulation of blood to the muscles you will be using. If you decide to continue stretching even after you have read all of my reasons not to, be sure to warm up first; do not stretch cold muscles.
Prolonged Stretching Limits the Ability of Muscles to Store Energy
Muscles are like rubber bands. They stretch and contract with each muscle movement. This constant stretching and contracting stores energy. For example, when you run, you land on your foot and the muscle stops contracting suddenly. The force of your foot striking the ground is stored in your muscles and tendons and this energy is released immediately to drive you forward. Your foot hits the ground with a force equal to three times your body weight when you run at a pace of six minutes per mile.
Up to 70 percent of the force of your foot strike is stored in your Achilles tendon and other tendons. This energy is released by your muscles and tendons to drive you forward for your next step. Stretching decreases the amount of energy you can store in muscles and tendons and therefore weakens you and you have less stored energy to drive you forward, so you have to slow down.
Contracting Stretched Muscles May Make Them Stronger
Athletes can become stronger by lengthening their tendons before they contract them. The longer a tendon, the greater the torque the muscle can put on a joint and the more force it can generate to make you faster and stronger. Passive stretches do not do this. It is more effective to try proprioceptive neuromuscular facilitation (PNF), in which the athlete stretches his tendons and then tries to contract the muscles from the lengthened position.
Gymnasts have been shown to increase their flexibility more after PNF stretching than after static stretching (Journal of Sports Medicine and Fitness, December 2014). Many athletes incorporate plyometrics into their training programs. For example, they jump off a series of steps consecutively. Their leg tendons are stretched when they land and they contract their muscles to do their next jump. However, this has been shown to increase their chances of injury.
Summing Up
Stretching offers little benefit to regular exercisers. There is some evidence that stretching a contracted muscle may offer a competitive athlete more power when that muscle is contracted, but stretching contracted muscles may increase susceptibility for injuries. Activities such as yoga that involve stretching motions can be beneficial and enjoyable, but they should not be used just before or just after a competition or session of hard exercise.
Dr. Gabe
What causes achilles tendinitis? I’ve been in pain for some time and am being told by my PT to warm up, do a variation of a leg lift, and the stretch my calf and Achilles’ tendon. I’m trying this and it’s not really helping as this has been going on for almost a year. Any general advice would be greatly appreciated.
Hi John,
I have suffered from a damaged Achilles for many years. What works for me is self massage – a routine I read about in a book on running injuries. Basically, I start by squeezing and wiggling the calf muscle side to side, and then do a few different massage techniques for a few minutes each. I knead the back of the leg from the calf down to the heel. I use my fingers to push down and move them across the calf from the top down to the heel and I do the same going lengthwise, up and down the area. I have found that this really helps reduce pain and prepares the leg for riding without Achilles issues. I bet you can google self massage for Achilles and come up with a routine like I follow.
Hope this helps,
Jim
Hi John,
I suffered from achilles tendinitis and it took over 2.5 years of care to resolve itself – It was the most frustrating injury I’ve ever had to deal with. I ended up having to wear a boot/splint while sleeping at night (and during the day for a shorter time frame). One of the first things my podiatrist said to me when we first met was “this is going to take way longer than you think it is.” He was right. I was still able to cycle in a limited capacity, but running/sprinting/hiking were off the table. Good luck and sorry to hear about your injury.
This is one of the best articles I’ve read in a long long time.
The most important thing you can do for Achilles tendonitis is gluteal strengthening. If you think about it, the glutes control where and how your foot and ankle move. I struggled with this for 2 yrs and worked with a terrific physical therapist
My personal experience (I’m 70) has been, that by post exercise stretching, I’ve been able to decrease nerve impingement issues related to arthritis. I’ve also noticed that after a “hard” ride, I have less muscular soreness and am less prone to cramping. if I stretch immediately after the ride.
I would like to hear doctor Mirkin’s views on stretching an IT band. My IT bands become painful if I cycle a lot, and a combination of driving long distances combined with cycling seems to be the worst. Stretching the IT band when it is sore helps with mobility, I can walk without limping. Then at some point the inflammation goes away, I stop stretching and all is well for a while. Then the tightness returns I stretch for a while and it goes away.
I am 81 years old and this problem started when I was riding double centuries 20 years ago.
I have similar issues
I’ve been a coach since 1965 and have multiple post graduate degrees in Motor Learning, Neuropsychology and Neurophysiology. I’ve been an very serious endurance athlete since 1978 (multiple times a member of Team USA Age Group World Championship teams). All the research I’ve read, my personal experience and my coached athlete’s have shown that there is no benefit to stretching, either before or after exercise. In fact some empirical peer reviewed research shows that stretching increases the risk of injury and slows the recovery from injury. I’ve always used and coached my athletes to use “dynamic” stretching – moving to improve range of motion (ROM) and never “static” stretching. The biomechanical difference is that dynamic stretching involves contraction of opposing muscles. The physiology involved is that muscles relax when their opposing muscles contract, while forcing a muscle to lengthen while the opposing muscle is in a relaxed state causes the “stretched” muscle to contract and oppose the lengthening. This is a basic preventative process that protects the muscle from :”tearing”. An example of dynamic stretching is swinging one leg forward to the limit of ROM. During the forward swing the hip flexors contract causing the glutes to relax,. As an aside, it is proven (peer reviewed empirical research) drinking chocolate milk within 30 minutes of completing a workout significantly decreases recovery time. I’ve only suffered from 3 or 4 injuries related to a workout and have recovered from hard workouts and races typically within 24 hours. I finished third in a three day stage ultra and ran an 18:24 5Km race the next weekend when I was in my 50’s.
I think you are addressing muscle stretching, but the IT band is not a muscle and seems to have its own behavior pattern. I do not know how to dynamically stretch an IT band. It would be very interesting to hear if you have a method of doing this
Roger, the ITB gets sore when the hip flexors and hip stabilizing muscles weaken and/or shorten. Cycling (and driving and running) is a single plain movement (or no movement) so an imbalance develops and the ITB gets pulled and becomes painful. Soccer players and basketball players rarely suffer ITB pain. They do a LOT of lateral movement. The best way to fix painful ITB is to do side shuffles, crossovers and lateral leg swings. I have athletes do a lateral lung – step to the side, squat and rotate on the leg you stepped sidewards with, repeat stepping with the other leg. Any movement that is lateral will help. I don’t believe rollers, or massage will do anything to help the cause, they may provide temporary relief, but the problem will return. Of course you could play soccer or basketball on the days you don’t cycle! All of these issues/problems/pain are the result of an imbalance and loss of ROM. An interesting study in the 1980’s correlated Masters Track champions with training volume (both time and distance), training intensity and finishing place. Surprisingly, none of that information correlated positively with finishing place. What was the best (and statistically significant) predictor of finishing place was how high the athletes got their heels during their run (measured with video analysis). I have used that with my athlete’s running technique and they have improved their speed and reduced/eliminated typical injuries. The relation to cycling is similar, improving your range of motion. I have some cycling/pedaling techniques that have worked, but they are not commonly recognized as recommended pedally techniques (don’t pull up on the pedals, only push down and “tap dance” on the pedals – get your feet out of the way as quickly as possible after the burst of force downward on the pedal). It’s the same biomechanical and kinesiological technique as getting your heels up when you run.
I asked Dr. Mirkin via his website how to increase ROM since stretching is not recommended. No reply yet. Neil Cook answers the question with his recommendation to employ dynamic stretching. Makes sense, especially with his explanation. When my current sciatica resolves I will swing legs, rotate ankles and work quads (how? Perhaps deep lunges). This is one of the most useful articles by Dr. Mirkin I’ve ever read. I’m 72, male, fairly fit.
David, to increase ROM of your quads I recommend two things. First as you swing your leg forward, continue the swing backward getting your heel close to your butt. The second you do while running,. Try to kick your heels against your butt. This will be difficult at first, so start by jogging very slowly and put your hands on your butt (palms facing backward) and bring your hips to your hands. Do 4 x 50 meters EVERYDAY and you’ll increase the ROM of your quads. As an added benefit you;’ll also run faster, your feet will be on the ground for as shorter period of time. If your don’t run, the butt kicks will help your tightness and your cycling. As a cyclist (runners have this same problem) you also need to strengthen and increase the ROM of your hips. Side shuffles, or just swinging your leg to the side and then across your body will help this (and ITB issues). Cyclists and runners only move their legs forward and backward, not sideward, which lessens ROM and causes an imbalance in stabilizing muscle strength. I’d do these exercises every day, and before and after cycling (and running). I have a list of warm-up and warm-down exercises that will help cyclists as well as runners. The entire set takes about 15 minutes and should be done even when you don’t cycle (or run).
David, I forgot to mention a recommendation for your sciatica. Don’t sleep with a pillow. Sleep flat on your back or with a towel rolled up and under your neck. This will keep your spine straight and not aggravate the sciatica or compress any spinal nerves.
Neil, this is a good recommendation to the public in general. I see far too many people way younger than me (60) who are curling over like dried up leaves. Start your sleep on your back with either a very flat pillow or no pillow and let gravity do some magic to slowly remove exaggerated curves from your back. There should be some “S” curve but you should be able to walk with your head upright over your hips.
Dr. Gabe Mirkin:
I do some basic Yoga poses every morning to get this old (87) body awake and moving. Yoga is really stretching but is it not beneficial?
Yes, in my experience stretching is beneficial. I think studies have not found it helps much before or after hard exercise but it is quite important for relaxation, toning, and preventing shortening and tightness. I used to get pain in my gluteus maximus muscle near the hip joint when doing TT position. The tight muscles were generating inflammation in the outer muscle covering. Laying on my back and stretching those muscles by pulling my knees to my face fixed that immediately. I still do that as well as stretch every other muscle I can imagine using free form Tai Chi motions mostly from a standing “Horse” position. Do that twice per day. Always sleep like a baby and have excellent balance. Also the act of comprehensive stretching keeps you aware of the state of your body in a detailed fashion in the sense that you notice subtle aches, pains, swelling, balance anomalies, etc and can address them realtime.
Neil, Many thanks for your reply which I found very interesting and consistent with my own experience.
I am 81. I raced bicycles from the age of 14 to 19 then gave up cycling. I played soccer seriously from the age of 30 to 62, at which point my left knee was ready for a replacement, so I gave up soccer and returned to cycling.
Cycling rehabilitated the knee up to a certain level, I can now walk and bike, but I have to be careful not to twist or put side loads on the knee ( I even have to be careful turning over in bed) So as you point out, it is this lack of sideways motion which is causing my IT problems. My right IT band is not as bad as the left as I probably allow some limited lateral movement on that side. So now I have to work out how to exercise the IT band laterally without damaging the knee
Roger
It just isn’t that simple.
Perhaps the problems here are 1) that there is no one-size-fits-all answer to whether stretching can improve anything, and 2) perhaps it can help in areas other than improved strength and race results. As I have learned, some people are born with loose, limber bodies, others (including me) more tightly knit frames. In my case, the static stretching involved in yoga and dance classes keeps me far more comfortable all the time (resting, walking, running, cycling, truly any type of movement or rest) than anything else I have found. And yes, I suspect I have tried it all. On the other hand, people I know with more limber frames are often hurt by stretching; they do not always have enough strength to support themselves if they are born with the flexibility of a contortionist. And for me, although I agree that static stretching is not a good way to start an activity involving strength, failing to stretch after a hard ride or run is almost sure to leave me leaping out of bed in the night to get rid of the cramps that follow. Finding proper ways to stretch, and to use that invaluable foam roller, have changed my life. I am 68 and move comfortably through long multi-day rides and just about anything else that comes up. Before I figured out my particular needs, I felt like the Princess and the Pea. Lots of pain, lots of general discomfort. My body feels younger than it did when I was 35.
That mirrors my experience as well. Middle of the night cramps were an unwelcome experience until I incorporated some static post ride stretching.