“Ya gotta stretch before you work out!”
How often have you heard this advice? Lots of times, I’ll bet.
But it’s only kinda sorta true.
Stretching is traditionally recommended pre-exercise as a way to reduce injuries. Unfortunately, research and real life doesn’t support the stretching-reduces-injuries theory.
The Centers For Disease Control And Prevention (CDC) dug through all the research on stretching and injuries and concluded that people who stretch are no less likely to suffer injuries than those who don’t and that stretching does nothing to prevent injuries.
And even worse, several studies have found that stretching before exercise actually makes you more likely to get injured.
Stretching before a workout doesn’t make you more flexible either. There’s a limit to how far a muscle can be stretched…
Picture a steak. You can grab the ends and pull hard, and it will stretch a bit. Keep pulling and pulling and it won’t stretch, it will rip. Your muscles are like that steak. There’s a limit to how far you can stretch before you start ripping.
Stretching beyond your limits weakens your tendons and ligaments. (Loose joints might give you a bigger range of motion though, at the high cost of greatly increased chance of injury)
The British Journal Of Sports Medicine stated that test subjects’s “flexibility index decreased significantly after stretching training.”
The warm-up aspect of stretching is also overrated. Stretching doesn’t contract your muscles (muscles are designed to do only one thing: contract). Contraction is what pulls blood into the muscle and bumps your metabolism to produce heat as a byproduct of effort. No muscular contraction, no warm up.
Stretching before you are warm is another good way to injure yourself, incidentally. Pulling the ends of a cold rubber band make it more likely to snap. Cold taffy doesn’t stretch out, it breaks. Your muscles do this too – a cold muscle getting stretched out will tear.
Stretching a muscle makes it weaker. You have these little things called Golgi Tendon Organs in your tendons that are stretch sensors. When they feel a stretch they try to contract your muscles to protect your muscles and joints from injury. if you hold a stretch long enough (and without going too far), the golgi tendon organs “turn off” and allow your muscle to stretch a bit more.
The problem with relaxed golgi tendon organs is that they are designed to help your muscles contract. Turn them off, and you’ve instantly become weaker. This not only affects your strength, speed, power, and endurance; your muscles are what support your joints – and if you turn off your support system, you’re left with no protection from moving your joints beyond their range of motion. Moving your joint outside of its range of motion = injury.
Weakened muscles from stretching also limit how effective your workout will be (while also making you more likely to get injured). If you’re training to lose fat and re-shape your body, being stronger means you can exercise with more weights, go longer, do the exercises better, burn more calories, and raise your metabolism higher.
The American College Of Sports Medicine published a study that checked out the effect that stretching has on strength. They tested hamstring strength and then the next session had subjects stretch their hamstrings before being tested. Strength declined every time after stretching, even if the stretch was only held for 30 seconds.
So really, stretching doesn’t do anything that common knowledge holds it does. Stretching doesn’t warm you up, make you more flexible, make you stronger, or protect you from injury.
Stretching a muscle weakens it.
Stretching your working muscles before practice (in athletes) or a workout is like going in overtrained and tired. You’ll perform on an inferior level and be more likely to get injured.
That’s why you don’t want to stretch your prime mover muscles before exertion. Weakened hamstrings, quads, and shoulders lead to injury and impaired performance. Of course, what are the most often stretched muscles? Hamstrings, quads, and shoulders…
Now, when is stretching a good thing?
You can slightly increase a muscle’s range of motion with stretching if it’s not done too vigorously. And stretching is ideally done an hour or so after your workout, when the muscles are still warm but not firing lots of electrical signals that cause contraction.
As your strength and mobility improves, your workouts themselves become active “stretches.” Sitting into a deep squat is a real world exercise that ensures you keep a big range of motion. (Doing real-world movements like squatting, pulling, pushing, and lunging means you’ll move freely, without even a risk of becoming “muscle bound”)
It’s time for the big idea: Sometimes making a muscle weaker is a good thing!
Really. After all the slams on stretching so far, sometimes you really do want to make a muscle weaker.
When a muscle is in a contracted position all day, it shortens and becomes very tight. This can pull your body out of alignment and really mess you up when you try to move.
So you can stretch that muscle to weaken it and let your joints get back into alignment.
Time for a few examples of when stretching a muscle to weaken it is what you should do…
Calves – Wearing shoes with a heel all day keeps your calf muscles shortened and they tighten up. Then when you go to exercise you can’t keep your feet flat on the floor, your knees shoot forward, and your back goes wonky.
So stretching your calves to weaken them allows you to keep your heels down when you exercise so your body is aligned and you have less risk of injuring other joints.
One caveat with stretching your calves: you don’t want to stretch them so much they’re weakened before doing power jumping exercises. In this case it’s better to warm them up with little hops and active squat stretches (like toe grab squats) instead of stretching.
Chest – Sitting hunched over in front of a computer (or on any chair, really) draws your shoulders forward and shortens your chest muscles. This in turn weakens the muscles of your back and raises your shoulder blades which weakens your shoulders and makes them more likely to get get injured. A tight chest is no bueno.
Opening and loosening your chest will let you activate your back muscles and keep your shoulders in place.
Again, you don’t want to weaken your chest muscles if you’re going to be doing aggressive chest exercises, but anything involving your back or lower body – go for it.
Hip Flexors And Piriformis – This is a big one. In fact, the most popular post on this website is all about just stretching your hip flexors (Here it is: One Exercise To End Lower Belly Pooch).
Sitting shortens these muscles and tips your hips out of alignment, which throws all of your exercise onto your lower back and prevents you from engaging your abs and glute muscles.
When your hip flexors are tight, your low back is going to hurt. And you see all the benefits from your core and butt exercises.
And a tight piriformis can cause shooting pain (and a shortened range of motion) through your low back and the back of your legs.
Weakening these two muscle groups with stretching is one of the best things you can do for yourself. We sit so much that it affects everything, and these are two great weapons you can use to counterattack.
There’s no caveat here, do the hip flexor stretch and the piriformis stretch as often as possible. I start every one of my workouts and the workouts of my clients with these two. Plus, stretch again throughout the day.
What doesn’t work about stretching:
- Doesn’t Warm You Up
- Doesn’t Decrease Injuries
- Doesn’t Increase Strength
- Doesn’t Increase Flexibility
- Doesn’t Improve Power Output
What stretching does:
- Slightly Increase Muscle Length
- Turn Off Contraction System
When stretching is a good thing:
- To Deliberately Weaken A Muscle To Improve Alignment