Stretching improves flexibility, but most of its other famous promises didn’t hold up

Key takeaways

• Stretching reliably increases how far your joints can move: a 2024 analysis of 77 studies found a moderate gain, with held stretches and PNF stretching beating bouncing or swinging moves⁴.
• In a 2014 analysis of 25 trials with 26,610 people, stretching didn’t reduce sports injuries, while strength training cut them to less than a third¹.
• A 2011 Cochrane review found that stretching before or after exercise changed soreness by 4 points or less on a 100-point scale, too little to matter².
• Holding a static stretch for a minute or more per muscle right before activity can cost about 4% to 5% of strength, power or speed, while shorter holds cost about 1%³.
• The American College of Sports Medicine’s 2011 position stand advises stretching each major muscle group at least 2 to 3 days a week, for about 60 seconds per muscle group in total⁹.

More than 2,000 adults in Norway and Australia signed up online for a stretching experiment. Half were assigned to stretch, and the rest carried on as normal¹.

When the researchers counted injuries, the stretchers’ risk was only 3% lower, a gap small enough to be chance¹. Two trials in Australian army recruits, with more than 2,400 men between them, found much the same¹.

Those three trials anchor a 2014 review in the British Journal of Sports Medicine, which pooled 25 trials of exercise programs meant to prevent sports injuries. Strength training cut injuries to less than a third, and balance and body-awareness training cut them roughly in half. Stretching did almost nothing¹.

That doesn’t make stretching useless, because it does one job very well: it lets your joints move farther. That matters when you reach a high shelf, check your blind spot while driving or pull on a pair of socks.

Flexibility is partly muscle and partly your nervous system’s permission

The federal Physical Activity Guidelines define flexibility as how far a joint, or a set of joints, can move¹¹. Muscles, tendons, ligaments, bone shape and skin all set limits, and so does your brain.

When you stretch, nerves in the muscle report the pull, and at some point you feel tightness and stop. That stopping point is set by sensation as much as by tissue⁶.

Researchers writing in the Scandinavian Journal of Medicine & Science in Sports in 2018 looked at 26 studies of regular stretching⁶. None of the programs ran longer than two months, and people stretched for about 19 minutes a week on average. Range of motion went up. The muscles and tendons themselves barely budged: measures of stiffness and muscle structure moved by trivial amounts⁶.

The bigger shift was in tolerance. People could take a stronger pull before they called it quits⁶. In programs under eight weeks, the authors wrote, the gains look mostly like changes in perception rather than changes in tissue⁶.

Changing the tissue itself may take longer or more intense programs, which haven’t been well studied⁶. Still, that’s good news: your body starts accepting a new range within weeks.

Stretching reliably buys range, and so does lifting through a full range

A 2024 meta-analysis in the Journal of Sport and Health Science gathered 77 studies of regular stretching⁴. A meta-analysis pools the results of many studies into one estimate. Compared with people who didn’t stretch, stretchers gained a moderate amount of range⁴.

Two details stand out. Held stretches and PNF stretching, a contract-then-relax method explained below, produced bigger long-term gains than bouncing or swinging styles. And more stretching wasn’t clearly better: the volume, intensity and frequency of the programs made no significant difference⁴. Women gained a little more than men⁴.

Now the surprise: you don’t have to stretch to get more flexible. A 2023 analysis of 55 studies in Sports Medicine found that strength training with weights or other resistance improved range of motion about as much as stretching did⁵. Adding stretching to lifting gave no extra gain on average⁵.

Previously inactive people gained the most, though body-weight-only training produced no clear gain⁵. The key is moving through a full range under load: a deep squat, a full overhead press, a lunge that lets the back knee sink. A 2025 panel of stretching researchers noted that strength training through the full range also improves flexibility⁸.

The federal guidelines agree that stretching increases flexibility. But time spent only on flexibility doesn’t count toward your weekly aerobic or muscle-strengthening targets¹¹. Stretching is an add-on, not a substitute.

The injury promise failed its biggest tests

Coaches have long told players to stretch so they won’t get hurt. In 1998, the American College of Sports Medicine (ACSM) added flexibility training to its fitness recommendations for the first time¹⁰.

The trials didn’t back up the injury idea. In the 2014 review, the three stretching trials enrolled about 4,600 people in all, and stretchers’ pooled injury risk was 0.96 times that of non-stretchers¹. The plausible range ran from a 15% drop to a 10% rise. Strength training’s figure was 0.32, based on four studies¹.

That’s a thin base, mostly army recruits plus one internet trial. Official bodies have read it the same way, though. ACSM’s 2011 position stand said a link between flexibility and fewer injuries hadn’t been shown⁹. The federal guidelines say it’s unclear whether flexibility work lowers injury risk¹¹.

One caveat cuts the other way. A 2016 review found no clear effect of held or PNF stretching on overall or overuse injuries, yet its authors still advised stretching within a warm-up that ends with active movement, partly to help limit muscle injuries³.

In 2025, a panel of 20 stretching researchers went further. Using a formal method called a Delphi process, which required 80% agreement, they concluded stretching is not an all-around injury-prevention strategy⁷. The University of Klagenfurt’s announcement put it plainly: don’t stretch for that purpose⁸.

If fewer injuries is your goal, the 2014 numbers point to strength and balance training, done steadily over time¹.

Stretching won’t erase soreness or fix your posture

Soreness that peaks a day or two after hard or unfamiliar exercise is called delayed-onset muscle soreness. Stretching seems like the obvious cure, but it isn’t.

Cochrane, an international network known for careful, independent evidence summaries, last updated its review of the question in 2011². It pooled 12 studies. All but one had just 10 to 30 people in the stretching group, but one field trial enrolled more than 2,300 adults².

Picture soreness on a 0-to-100 scale. A day after exercise, people who had stretched beforehand scored about half a point lower than non-stretchers, and those who stretched afterward scored about 1 point lower². The big trial asked people to stretch both before and after, and their worst soreness of the week came out 3.8 points lower². The authors judged that stretching doesn’t produce “clinically important reductions” in soreness in healthy adults².

The 2025 expert panel agreed that stretching doesn’t speed recovery after exercise, and it found that stretch training doesn’t improve posture⁷. A rounded upper back won’t straighten out from stretching alone, the Klagenfurt announcement noted⁸.

If soreness is the problem, easy days, sleep and good food deserve your attention first. Our article on recovery gadgets weighs what helps.

Before a workout, keep static holds under a minute

The old warning says stretching before exercise makes you weaker. The truth is narrower.

A 2016 systematic review in Applied Physiology, Nutrition, and Metabolism looked at testing done 3 to 5 minutes after stretching³. Static stretching lowered strength, power or speed by about 3.7% on average, and PNF lowered it by about 4.4%. Dynamic stretching raised performance by about 1.3%³.

Hold time mattered most. Holding a muscle 60 seconds or longer cut performance by about 4.6%, while shorter holds cost about 1.1%³. When people moved actively after stretching, the drop was no longer clear³.

So if you like a few stretches before a hike or a game, keep them. Hold each one for less than a minute, then move: brisk walking, leg swings, an easy jog. Save long holds for after activity or a separate time of day. Our companion article on mobility covers movement-based warm-ups.

How much stretching is enough

ACSM’s 2011 position stand, as summarized by exercise scientist Len Kravitz of the University of New Mexico, set out a simple dose⁹:

• Stretch each major muscle group at least 2 to 3 days a week. Daily stretching works better.
• Go to a feeling of tightness or slight discomfort, never pain.
• Hold 10 to 30 seconds. Older adults may benefit from 30 to 60 seconds.
• Repeat 2 to 4 times, for about 60 seconds in total per muscle group.

The 2025 expert panel went further and attached minimums to particular goals, according to a University of Klagenfurt summary of its work⁸. If you want a same-day boost in range, any style of stretch works, done for two or more sets with holds of 5 to 30 seconds. Making stiff muscles less stiff over time takes more: four or more minutes of static stretching, five times a week⁸.

The panel also tied longer static sessions to blood vessel function: 7 minutes for a short-term effect and 15 minutes for a lasting one⁸. Treat that as a maybe. The panel itself said stretching may help blood vessels but more research is needed⁷.

Flexibility fades with age, at very different rates

A 2008 study, done mostly at one Rio de Janeiro clinic, measured 20 joint movements in 4,711 non-athletes ages 5 to 91¹². Each movement was scored from 0 to 4. Flexibility fell with age in both men and women¹².

Women were more flexible from about age 10, and after 60 they scored 20% to 40% higher than men¹². The gap between individuals also grew with age: children’s scores sat close together, while older people’s spread widely¹².

These were snapshots of different people, not the same people followed for years, so the study can’t show how much habits explain¹². But both big meta-analyses tested age, and neither found that it significantly changed the gains from training⁴⁵. ACSM’s main change for older adults is longer holds⁹.

Some people have the opposite issue. Joint hypermobility means joints move farther than usual because the ligaments that hold them are looser¹³. The UK’s children’s physiotherapy association calls it a normal finding, not a disease, unless it causes symptoms such as pain, tiredness or frequent falls. Then it may be called hypermobility spectrum disorder¹³.

Depending on the criteria, 7% to 36% of children have hypermobile joints, according to a Canadian study the association cites¹³. Its advice centers on strengthening the muscles around the joints and pacing activity; stretching isn’t on its list¹³. If you’re very bendy and your joints hurt or slip out of place, ask a clinician or physical therapist for an assessment.

A 10-minute daily routine and a when-to-stretch table

Stretching fits natural-health values well. It’s free, needs no gear and asks you to pay attention to how your body feels. The evidence only asks you to expect the right things from it: more range, not a shield against injury.

This routine gives most muscle groups about 60 seconds, the ACSM dose⁹. Most adults can do two 30-second holds per side, and older adults can do one 60-second hold. Breathe slowly and stop at tightness, never pain.

1. Warm up (2 minutes). Walk around the house, march in place or climb a flight of stairs a few times. Keep it light: by the federal talk test, moderate effort lets you talk but not sing, so stay a notch below that¹¹.
2. Calves (1 minute per side). Hands on a wall, one foot back, back heel down, back knee straight. Lean in.
3. Back of the thighs (1 minute per side). Sit on the front edge of a sturdy chair. Straighten one leg with the heel on the floor. Hinge forward from the hips with a long back.
4. Front of the hips (1 minute per side). Kneel on a cushion beside a chair, holding it for balance, one foot forward. Tuck your tailbone and shift your weight forward.
5. Chest and shoulders (1 minute). Stand in a doorway with your forearms on the frame. Step slowly through.
6. Side reach (30 seconds per side). Stand tall, raise one arm overhead and lean gently to the opposite side.

Want to try PNF on step 3? Press your heel into the floor for 3 to 6 seconds at gentle effort, relax, then stretch again⁹.

Your goal	What works best	When	Evidence rating
Reach farther and move more freely	Static or PNF stretching most days, or full-range strength training	Any time you’re warm	Strong evidence45
Get ready for a hike, game or lift	Movement-based warm-up; static holds under 60 seconds, then move	The 10 minutes before	Strong evidence that short holds cost little3
Avoid sports injuries	Strength and balance training	2 to 3 days a week, ongoing	Evidence says no for stretching alone1
Ease next-day soreness	Time, sleep and easy movement	The days after hard exercise	Evidence says no for stretching2
Improve posture	Don’t count on stretching for this	Not applicable	Evidence says no for stretching, per a 2025 expert consensus7

What the evidence shows

Claim	Evidence rating	What it rests on
Regular stretching increases range of motion	Strong evidence	77 studies4; federal guidelines11
Full-range strength training increases range of motion	Strong evidence	55 studies, with gains similar to stretching5
Long static holds right before activity briefly reduce strength and speed	Strong evidence	Systematic review; holds under 60 seconds cost about 1%3
Regular stretching helps blood vessel health	Promising but early	Expert panel says more research is needed7
Stretching alone improves long-term health, such as heart disease risk or lifespan	Not enough evidence	Federal guidelines call its health benefits unknown11
Stretching prevents sports injuries overall	Evidence says no	Three trials with about 4,600 people1; a 2016 review still favors stretching inside a warm-up3
Stretching prevents or eases muscle soreness	Evidence says no	Cochrane review of 12 studies2
Stretching improves posture or speeds recovery	Evidence says no	2025 consensus of 20 stretching researchers7

Questions readers ask

The bottom line

Stretching is good at one thing: it lets your joints move farther, at any age, within a few weeks. It isn’t good at preventing sports injuries, erasing soreness or fixing posture, and the best evidence on all three points the same way.

Stretch most days if you enjoy it and want more range, with short holds before activity and longer ones after. For fewer injuries, put your time into strength and balance work. And if you’d rather lift than stretch, moving through a full range under load gets you much of the same flexibility.

Related reading

• Mobility means getting up, reaching and carrying, so practice the real moves
• Most adults skip strength training, though under an hour a week goes a long way
• Sleep, food and easy days beat most recovery gadgets
• Vibration plates didn’t build bone in a year-long trial, though falls are another story
• Wellness advice is written for an average person who doesn’t exist

Sources

1. Lauersen JB, Bertelsen DM, Andersen LB. “The effectiveness of exercise interventions to prevent sports injuries: a systematic review and meta-analysis of randomised controlled trials.” British Journal of Sports Medicine, 2014;48:871-877. pubmed.ncbi.nlm.nih.gov
2. Herbert RD, de Noronha M, Kamper SJ. “Stretching to prevent or reduce muscle soreness after exercise.” Cochrane Database of Systematic Reviews, 2011, CD004577. cochranelibrary.com
3. Behm DG, Blazevich AJ, Kay AD, McHugh M. “Acute effects of muscle stretching on physical performance, range of motion, and injury incidence in healthy active individuals: a systematic review.” Applied Physiology, Nutrition, and Metabolism, 2016;41(1):1-11. ro.ecu.edu.au
4. Journal of Sport and Health Science. “Chronic effects of stretching on range of motion with consideration of potential moderating variables: A systematic review with meta-analysis.” March 2024 (DOAJ record). doaj.org
5. Alizadeh S, Daneshjoo A, Zahiri A, et al., Behm DG. “Resistance training induces improvements in range of motion: a systematic review and meta-analysis.” Sports Medicine, 2023;53(3):707-722. lida.sport-iat.de
6. Freitas SR, Mendes B, Le Sant G, Andrade RJ, Nordez A, Milanovic Z. “Can chronic stretching change the muscle-tendon mechanical properties? A review.” Scandinavian Journal of Medicine & Science in Sports, 2018;28(3):794-806. research-repository.griffith.edu.au
7. Warneke K, Thomas E, Blazevich AJ, et al., Wilke J. “Practical recommendations on stretching exercise: a Delphi consensus statement of international research experts.” Journal of Sport and Health Science, 2025;14:101067. pure.northampton.ac.uk
8. University of Klagenfurt. “Scientifically grounded recommendations for stretching published for the first time” (news release on Warneke et al.). University of Klagenfurt, July 7, 2025. aau.at
9. Kravitz L. “From 1998 to 2011: ACSM Publishes Updated Exercise Guidelines” (summary of Garber CE, et al., “Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults,” Medicine & Science in Sports & Exercise, 2011;43(7):1334). University of New Mexico. unm.edu
10. Morey SS. “ACSM Revises Guidelines for Exercise to Maintain Fitness.” American Family Physician, 1999;59(2):473. aafp.org
11. U.S. Department of Health and Human Services. “Physical Activity Guidelines for Americans, 2nd edition.” HHS, 2018. odphp.health.gov
12. Araújo CGS. “Flexibility assessment: normative values for Flexitest from 5 to 91 years of age.” Arquivos Brasileiros de Cardiologia, 2008;90(4):280-287. pubmed.ncbi.nlm.nih.gov
13. Association of Paediatric Chartered Physiotherapists (Chartered Society of Physiotherapy). “Hypermobility and Hypermobility Spectrum Disorder: Information for Parents and Carers.” APCP, 2023, reviewed June 2024. apcp.csp.org.uk
14. Leeds Beckett University, Carnegie School of Sport. “Health Screening Guidance” (based on ACSM’s Guidelines for Exercise Testing and Prescription, 10th edition). Leeds Beckett University, 2018. Www.Leedsbeckett.Ac.Uk
15. Whitfield GP, Riebe D, Magal M, Liguori G. “Applying the ACSM preparticipation screening algorithm to U.S. adults: National Health and Nutrition Examination Survey 2001-2004.” Medicine & Science in Sports & Exercise, 2017;49(10):2056-2063. digitalcommons.uri.edu