The Bendy Kid on the Soccer Field: Understanding Joint Hypermobility in Growing Athletes and How Physical Therapy Can Help

If your child could always sit in positions that made other parents wince, wins the flexibility test at every practice, bends a thumb back to the forearm as a party trick—and has now started saying a knee feels wobbly or a shoulder slipped reaching for a ball—this is worth understanding rather than panicking about.

Joint hypermobility in children is common. In a population study of fourteen-year-olds published in Arthritis & Rheumatism in 2011, 27.5 percent of girls and 10.6 percent of boys met the threshold for generalized joint hypermobility. Most were fine. Some were not, and the difference is rarely the range itself.

The good news? The part that makes the difference—muscle control around the joint—is the part that responds to training.

At Rooted Motion Physical Therapy, we assess young athletes in the spaces they actually play in. Here is what we would want you to know before the fall season.

Why Does the Same Body Win in One Sport and Struggle in Another?

This is the part that confuses families, and it is the most useful thing in this article.

A body that moves further than average is an advantage in gymnastics, dance, swimming and diving—sports that reward range and where the athlete controls the movement. The same body on a soccer or basketball court meets forces it did not choose: a planted foot, a shoulder charge, a landing that goes slightly wrong. Range that is an asset when you direct it is unprotected when someone else supplies the force.

Extra range is not the problem. Uncontrolled range is. Schematic, not to scale.

Think of a camera tripod with the leg locks loosened. Nothing is broken and the legs still work. It simply travels further than it should before something stops it, so something else has to do the steadying. In a person that something else is muscle—and unlike the range, muscle control can be built.

Which Joints Actually Carry More Risk?

Here the evidence is more specific than the general worry usually is, and it is also more reassuring than most parents expect.

A meta-analysis in The American Journal of Sports Medicine in 2010 pooled eighteen studies and found that hypermobile participants in contact sport had a raised risk of knee injury—an odds ratio of 4.69—while finding no increased risk of ankle injury at all.

The knee result and the ankle result come from the same review. Both belong in the conversation.

That knee figure needs its range attached to be honest: the confidence interval ran from 1.33 to 16.52. An interval that wide means the risk is probably raised but its size is genuinely uncertain.

And here is the part that rarely gets passed on to parents. The studies done specifically in children and young teenagers have mostly not found that raised risk. A Danish study of 999 children aged nine to fourteen, published in BMC Musculoskeletal Disorders in 2015, found no significant association between generalized hypermobility and either traumatic or overuse knee injuries, and its authors questioned whether hypermobility is a clinically relevant knee-injury risk factor at that age at all. A 2017 study in the Journal of Orthopaedic & Sports Physical Therapy of 132 elite adolescent athletes averaging fourteen years old likewise found no association with injury prevalence, recurrence, or missed training.

So the honest summary is this: the pooled adult-and-mixed-age data suggest a raised knee risk in contact sport, and the studies done in your child's actual age group largely do not. One proposed explanation is that young athletes who keep training develop enough active muscular control to compensate—which, if true, is an argument for preparation rather than for worry.

The shoulder is the other joint worth attention, with the same caution. A 2021 meta-analysis in BMC Musculoskeletal Disorders found roughly threefold odds of shoulder injury in hypermobile athletes—but that pooled figure is driven by athletes with specifically loose shoulders. For generally bendy athletes, the kind this article is about, the odds ratio was a far more modest 1.97. The authors graded the whole body of evidence as low quality, said the estimate will likely change, and studied athletes averaging nearly twenty rather than thirteen.

What If They Quietly Stop Playing?

A 2025 study in Pediatric Rheumatology put accelerometers on adolescents aged thirteen to seventeen and found those with hypermobility spectrum disorder or hypermobile Ehlers-Danlos syndrome spent significantly more time sedentary and less in moderate-to-vigorous activity than peers.

That study cannot tell us which came first, and we will not pretend otherwise. The picture most of the literature describes is a loop rather than a one-way street: discomfort reduces activity, and reduced activity erodes the muscle control the joints were relying on, which makes the next season harder. Catching that loop early is generally easier than reversing it later.

What Actually Helps, and in What Order?

International consensus guidance published in the American Journal of Medical Genetics in 2017 sets out an order that has held up well: control of the trunk and the joints closest to the body before the individual sore joint, closed-chain work before open-chain, and low load with higher repetitions before adding resistance.

In practice that generally looks like:

• Building control of the hip, trunk and shoulder blade first, even when the complaint is the knee.

• Loading with the foot or hand fixed—squats, step-downs, work against a wall—before free-moving resistance.

• Adding repetitions before adding weight, and adding speed and direction change last.

• Rehearsing landing and cutting deliberately, since contact sport supplies those without warning.

One honest caveat, and it cuts toward patience. There is no high-quality trial establishing how heavily to load a hypermobile adolescent; the guidance above is expert consensus rather than trial-derived, and heavy loading in this age group is neither validated nor ruled out. A trial in adults found higher loads outperformed lower ones at the shoulder, but that has not been tested in thirteen-year-olds. The conservative sequence is the safer default, progress is often slower than in other young athletes, and measurable change can take months.

What Should You Tell the Coach?

Less than you think, and more specifically than you think. A coach does not need a diagnosis. A coach needs two or three concrete things.

• Which movements your child is currently working on controlling, so a warm-up can include them rather than work against them.

• What the plan is when something feels unstable mid-session, so nobody has to improvise in front of a team.

• That extra flexibility is not an invitation to stretch further, since range is generally not the limiting factor here.

When Should You Get It Looked At?

Extra flexibility on its own does not need treating. It is worth an assessment when a joint has given way or dislocated, when pain persists beyond a few weeks or wakes your child at night, when they have started avoiding parts of a sport, or when fatigue seems out of proportion.

That last one matters. Hypermobility and orthostatic problems travel together often enough that clinicians now look for one when they find the other—in the largest pediatric series, more than half of children with postural orthostatic tachycardia syndrome also had a hypermobility disorder. The link runs less predictably in the direction that concerns you here, and why the two cluster is still unsettled. But dizziness on standing and fatigue out of proportion to activity are worth raising with your child's physician rather than treating as ordinary tiredness.

The Rooted Motion Difference

We provide one-on-one mobile care throughout Richmond, Henrico, Chesterfield and Midlothian. For a young athlete that means being assessed on the surface they play on, with a program that fits around practice rather than competing with it. We are also comfortable telling you when extra range is simply how your child is built and needs nothing more than sensible loading.

Ready to Take the Next Step?

If your child is flexible, sore, and heading into a fall season, a proper look now is worth more than a wait-and-see. Schedule a one-on-one evaluation and we will build a plan around the sport they actually play.

Ready to move better and live rooted? Contact Rooted Motion Physical Therapy to schedule a one-on-one evaluation and begin a personalized plan built around the sport your child actually plays.

Research Used for This Article

1. Clinch J, Deere K, Sayers A, et al. Epidemiology of generalized joint laxity (hypermobility) in fourteen-year-old children from the UK: a population-based evaluation. Arthritis Rheum. 2011;63(9):2819-2827. DOI

2. Pacey V, Nicholson LL, Adams RD, Munn J, Munns CF. Generalized joint hypermobility and risk of lower limb joint injury during sport: a systematic review with meta-analysis. Am J Sports Med. 2010;38(7):1487-1497. DOI

3. Junge T, Larsen LR, Juul-Kristensen B, Wedderkopp N. The extent and risk of knee injuries in children aged 9-14 with Generalised Joint Hypermobility and knee joint hypermobility - the CHAMPS-study Denmark. BMC Musculoskelet Disord. 2015;16:143. DOI

4. Schmidt H, Pedersen TL, Junge T, Engelbert R, Juul-Kristensen B. Hypermobility in Adolescent Athletes: Pain, Functional Ability, Quality of Life, and Musculoskeletal Injuries. J Orthop Sports Phys Ther. 2017;47(10):792-800. DOI

5. Liaghat B, Pedersen JR, Young JJ, Thorlund JB, Juul-Kristensen B, Juhl CB. Joint hypermobility in athletes is associated with shoulder injuries: a systematic review and meta-analysis. BMC Musculoskelet Disord. 2021;22(1):389. DOI

6. Schubert-Hjalmarsson E, Fridolfsson J, Arvidsson D, Borjesson M, Lundberg M. Exploring physical activity patterns in adolescents with hypermobility spectrum disorder or hypermobile Ehlers-Danlos Syndrome. Pediatr Rheumatol Online J. 2025;23(1):69. DOI

7. Engelbert RHH, Juul-Kristensen B, Pacey V, et al. The evidence-based rationale for physical therapy treatment of children, adolescents, and adults diagnosed with joint hypermobility syndrome/hypermobile Ehlers Danlos syndrome. Am J Med Genet C Semin Med Genet. 2017;175(1):158-167. DOI

Educational disclaimer: This article is for general education and is not a substitute for an individualized evaluation. Seek prompt medical care for a joint that has dislocated or will not go back into place; severe pain, deformity or marked swelling after an injury; numbness, tingling or loss of circulation in a limb; fainting; or chest pain.