"Most people do not stretch," says Brion Gardner, MD, an orthopedic surgeon specializing in sports medicine at the Centers for Advanced Orthopaedics in Manassas, Virginia. "Some don't bother because they think it's boring, while others don't understand the importance of stretching."
So how bad is it really to skip stretching altogether? Stretching is the basis for flexibility, so if you want to enhance it, the American Council on Exercise (ACE) says those side bends are essential. Not to mention, flexibility is a core component of physical fitness.
What Happens When You Stretch a Muscle
Whether you're doing a spinal twist, hip opener or side bend, stretching helps your body move more freely.
"When you stretch, your nervous system sends a signal to a proprioceptive sensor called the Golgi tendon organ," says Anthony Wall, MS, a spokesperson for the ACE and member of the physical activity innovative collaborative of the National Academies of Medicine. "The Golgi tendon detects the change in tension and instructs your muscle to relax."
After about 7 to 10 seconds of stretching, your muscle will release some tension, at which point the spindles — long lengths of tissue within each muscle — extend, enhancing your range of motion.
"In the short term, the increased range of motion will last for 10 to 20 minutes after you finish stretching," Wall says.
But if you stretch regularly, then over time you will grow your overall range of motion. "This allows you to move effectively and properly in daily life," Wall says.
Exactly how long before you see a permanent payoff? "It depends how supple your muscles are, but as long as you are properly hydrated then you will probably start to feel differences in about five to six sessions," Wall says.
But if you don't stretch things out, here are few things that can happen.
You Can Develop a Rounded Upper Back
Folks who never stretch are more likely to eventually take on a hunchback appearance. "If you are not maintaining your flexibility, it can lead to poor posture," Wall says. "Gravity will hunch you forward — your shoulders will round and your chin will stick forward."
And improper alignment not only leads to issues like lower back and neck pain, but it can also cramp your lifestyle as you age. "As your posture gets progressively poorer, it impacts your ability to perform normal activities of daily living, like walking up a flight of stairs, sitting down on a chair or reaching under a bed to get something," Wall says.
A classic example is putting on a sweater in the winter: "If you lack flexibility and don't have much range of motion through your shoulders, it becomes challenging to raise your arms and maneuver them through your sleeves," he explains.
While skipping stretch sessions probably won't have much of an impact when you're in your 20s, your flexibility declines each decade thereafter. "Stretching resets our posture and is one of the ways to combat the negative adaptations associated with aging," Wall says.
You’re More Likely to Get Hurt
The primary reason flexibility declines with time? The content of H2O in your body decreases as you age. As a result, not only will you feel stiff instead of supple — but you are also more injury-prone.
"A lower concentration of water within your muscle, ligament and tendon cells can lead to tears and injury," Dr. Gardner says. Case in point: When your tendons aren't as spongy, it's easier for them to pop under strain. And as the discs cushioning the vertebrae in your lumbar spine (lower back) become friable, they can cause pain.
With many Americans leading increasingly sedentary lifestyles, this becomes more of a concern. A June 2017 study in the Saudi Journal of Sports Medicine found that the longer students spent sitting, the more contracted their hamstrings were.
"When your resting muscle position shortens due to extended sitting, it can make you prone to injury," Wall says. "For example, if you stand up suddenly, you are more likely to pull a muscle."
Since joint mobility is also a driver of balance, people with tight muscles are at a greater risk of falling. Adults who participated in stretching exercises exhibited a significant improvement in balance, according to a November 2018 study in the Journal of Anatomical Science and Research. "For instance, having a greater range of motion in your ankles improves your balance when going up and down stairs," Wall says.
In addition, neglecting to stretch before working out may lead to sports injuries. "A 'cold' muscle will fatigue faster, which puts extra strain on the fibers around each muscle group and the tendons and ligaments attached to those muscles," Dr. Gardner says. "When your muscle is not loose, you are at a greater risk of injury within the muscle, as well as tendon and ligament tears."
Stretching pre-workout also gives your body a heads up that it's about to work. "It warns the muscle that it will be put under stress and that it should relax instead of fighting it," Wall says. "This protects you from injury — often when you hurt yourself, it's because you move too fast and the muscles aren't prepared."
It's also a good idea to stretch after exercise. "You run the risk of feeling sore if you don't allow your muscle fibers to recover gradually [via stretching]," Dr. Gardner says. "You can damage your muscle cells, leading to bursitis or tendonitis."
Without a good stretch, your muscles could contract and freeze up — and that's a recipe for pain. Dr. Gardner likens it to slamming on the brakes instead of slowly pressing down. "If you go from 100 to zero, your car will skid instead of coming to a controlled stop," he says. "Similarly, going from one extreme to another can cause injury."
You Might Not Be as Fast or Strong
Increased flexibility can improve strength, endurance and sport-specific training, according to the ACE. If your muscles are too tight, then you might not be able to activate the fibers necessary for explosive movements, the ACE says. For example, tight hip flexors prevent you from breaking out into a full stride when sprinting.
It's kind of like a rubber band; pulling the muscle back and then releasing it allows it to fly forward with greater speed. "Stretching a muscle to its maximum length gives it more energy to contract, leading to increased force, agility and a faster reaction time," Dr. Gardner explains. "In comparison, if you ask a 'cold' muscle to sprint, it won't go as fast or hard."
Stretching also boosts circulation. "When you stretch, you bring blood back into the muscles," Wall says. "That's important because when you activate a muscle, blood needs to come into the muscle to help facilitate that movement."
The Case Against Stretching
Some research suggests that stretching is not all it's cracked up to be. In fact, a February 2018 Physical Activity Guidelines Advisory Committee Scientific Report to the Secretary of Health and Human Services states, "Flexibility training is a common component of multicomponent physical activity programs but has not been sufficiently studied by itself, precluding assessment of its independent benefits, if any, on health."
"When it comes to injury prevention, the research is inconclusive in some areas and more supportive in other areas," Wall says. "The type of stretch, the conditions used and the population [studied] all affect the results, which makes it hard to translate for the general [public]."
For example, a June 2014 meta-analysis in the British Journal of Sports Medicine found that good balance and strength training significantly reduced the risk of sports injury, but stretching had no impact.
Meanwhile, a May 2020 article in Sports Medicine argues that stretching is not associated with decreased injury and mortality in people who are otherwise healthy and fit. (That said, a December 2020 study published in the Journal of Physical Activity and Health found that stretching is more beneficial than walking at lowering blood pressure.)
In other words, keep stretching it out. "There is still lots of research in this area [that] supports the rationale for stretching," he says.
How to Start a Stretching Routine
If flexibility training isn't in your wheelhouse, you might be clueless about where to begin. Start with a few basic stretches.
"At first, target the muscles you are most comfortable stretching, and do it for a short amount of time," Wall says. "Over time, you can start to incorporate other body parts and make stretching a regular part of your fitness routine."
If you have trouble getting motivated, write down your stretching goals. "It's important to understand the value of stretching for you," Wall says. From less soreness to better balance to improved athletic performance, what do you hope to change about your lifestyle or the way you feel through greater flexibility? Remembering what you're working toward can help keep you on track.
And although it's tempting to limber up while you're watching TV, listening to a podcast or talking on the phone, stretching newbies should avoid multitasking. "If you are too focused on other things, then you might miss some signals about how far you can safely stretch," Wall says. "Stretching is a skill you need to develop."
That said, anything is better than nothing, so if the only time you can carve out to forward-bend is while tuning into your fave show, go with it.
So, How Bad Is It Really to Never Stretch?
It depends on what activities you do. "If you play tennis, tight muscles put you at risk of a ligament or tendon injury," Dr. Gardner says. "In terms of your general lifestyle, it might make you feel less stiff when sitting at your desk or riding in the car for long periods of time."
Age is also a factor. "If you're in your 20s, not stretching might not present any issues at the moment, but I'm a strong proponent of thinking about what you want the back half of your life to look like," Wall says. "Eventually, you will see the cumulative effect of decades of not stretching — and it is much more challenging to increase your flexibility when you are in your 70s."
So stretch your imagination: Even if you're young and fit, fast-forward to your golden age. Staying pliable right now will help keep you happy and healthy years from now.
- Saudi Journal of Sports Medicine: "Extended Sitting Can Cause Hamstring Tightness"
- Physical Activity Guidelines Advisory Committee Scientific Report
- International Journal of Sports Physical Therapy: "CURRENT CONCEPTS IN MUSCLE STRETCHING FOR EXERCISE AND REHABILITATION"
- Sports Medicine: "The Case for Retiring Flexibility as a Major Component of Physical Fitness"
- Journal of Anatomical Science and Research: "The Effect of Static Workplace Stretching on the Balance in Computer Operators with a Single Leg Balance Test"
- American Council on Exercise: "The Impact of Flexibility Training on Performance"
- British Journal of Sports Medicine: "The Effectiveness of Exercise Interventions to Prevent Sports Injuries: A Systematic Review and Meta-Analysis of Randomised Controlled Trials"
- American Council on Exercise: "10 Reasons Why You Should Be Stretching"
- Journal of Physical Activity and Health: "Stretching is Superior to Brisk Walking for Reducing Blood Pressure in People With High–Normal Blood Pressure or Stage I Hypertension"