Have you ever had a friend whose party trick is to bend their thumb to their wrist, or contort a limb into a position that's just wrong (and a bit gross)?
Well, I've always been that person.
Most of my life I've been told I'm "double jointed", without even knowing what that meant, other than that I'm really flexible.
Turns out, there's a clinical definition for being too flexible — generalised joint hypermobility (GJH). So much clearer, right?
Hypermobility is both a genetic and acquired condition that affects the body's connective tissue, making it much more elastic than it should be.
This can be a problem because connective tissue is the stuff that holds us together.
It's in your organs, skin, muscles, blood vessels - pretty much everywhere. And it surrounds your muscles, joints, tendons and ligaments.
Loose limbs and injuries
When connective tissue has too much elasticity, you're at risk of injury because you need more control around your joints.
"You're constantly going further than what's considered the normal end range of a joint," explains Dr Verity Pacey, a physiotherapist and expert in GJH from Macquarie University and The Children's Hospital at Westmead.
This puts a lot of strain on your tendons, which attach muscles to bones, and your ligaments, which connect bones to each other at the joint.
By repeatedly pushing past "normal" range, you're getting micro traumas, which can lead to more serious injury, such as joint dislocation, ligament strains and tears, or tendon inflammation.
There's flexible and there's flexible
So the hyperflexible among us move far too much in our knees, hips, shoulders, elbows and ankles. We also tend to get joint pain, when our stretch-fests have gone out of hand.
One of the issues with GJH is that most people have no idea that they are too flexible.
It can be seen as a positive when it comes to certain activities - such as yoga, dancing and gymnastics. All that stretching feels really good.
It's not until we're injured and see a physiotherapist that we realise what's going on.
"There are plenty of people who don't show symptoms . . . and you may be drawn to a sport because of your flexibility," Dr Pacey says.
It's worth pointing out, there's a difference between GJH and hypermobile Ehlers Danlos Syndrome (EDS), which is much more serious.
Those with EDS often live with severe joint and muscle pain, have loose skin that bruises easily, suffer extreme fatigue, and are at risk of prolapses and hernias.
A cautionary tale
Yoga is my sport of choice and after a decade of stretching my limbs into "enviable" depths, I've been left with shoulder and hip issues that mean I am spending far too much time on rehabilitation.
Over the years I kept stretching myself further, until my already loose connective tissue probably resembled an old elastic band.
It wasn't until I became a personal trainer that I understood that hanging out on my joints was bad. Like most people, I thought my flexibility was cool. Now I see it as the karmic debt I'm repaying in this lifetime.
It's hard to know how many people have GJH because the criteria are so broad, explains Associate Professor Leslie Nicholson, leader of the Hypermobility and Performance Lab at the University of Sydney.
"There are figures at between 4 and 30 per cent of the population," she says.
Experts say it's hard pinpoint the cause of hypermobility, except that it's genetic and can be acquired. For example, ballet dancers who train themselves to become hypermobile.
Feedback system broken
So what's the solution to elastic-band limbs? Strengthening the muscles that surround the joints.
It won't stop you being hypermobile, but it can help control joint movement and reduce the risk of injury.
The frustrating part for the super flexible is that when they're strength training, they're constantly told to stop at "normal" range of motion. Often they don't know what that feels like.
"Ligaments, tendons and joint capsules have nerve endings that provide information on where you are in space and how much muscle activation is needed to control your joints," explains physiotherapist Nigel Morgan.
"But when they're chronically stretched over time, that feedback system is impaired, so your nervous system gradually receives less information. This makes it harder for you to control your movements."
Which is why people with generalised hypermobility shouldn't try to stop within 'normal' range.
"You can't really stop yourself going into that range especially when you are fatigued, so it's far better to learn control and strengthen your muscles in that excess range," Associate Professor Nicholson explains.
By doing that, you'll be training proprioception - your ability to sense the relative positions of your body parts - and improving the nervous system's feedback system, so you get better at controlling your joints.
Which means, in a dream world, that a ballet dancer who's super flexible will also have strength and control while doing insane things with their body.
Stay in the game for longer
In general, otherwise healthy people who have hypermobile joints can benefit from lifting weights several times a week.
The muscles you need to strengthen will depend on where you're too mobile, but building the major muscles that surround your joints is key, especially if it's your weight-bearing postural joints like hips, knees, shoulders and back.
Not only that, we need to learn to co-ordinate the muscles so they work in sync when moving our bones. Easier said than done.
"All muscles have a certain length where they're at their most efficient and that's based on typical range of motion," Dr Pacey says.
"But when you're hypermobile, your muscles are at a disadvantage. So when you need them most, they're at a less-efficient position."
Are you hypermobile?
Diagnosis of a more serious hypermobility disorder needs to be done by a doctor, but the easiest way to see if you have generalised joint hypermobility is with the Beighton score.
It tests the mobility around your major joints. Each joint (left and right) is one point for a total score out of nine.
Add a point each for pinky fingers that bend back 90 degrees, thumbs that can be bent to reach the forearm, elbows that straighten past 10 degrees, knees that straighten past 10 degrees, and hands that can lie flat on the floor with knees locked out.
Female hypermobility scores per age group:
- 3-7 years: 6
- 8-39 years: 5
- 40-59 years: 4
- 60-69 years: 3
- Over 70: 2
Male hypermobility scores per age group:
- 3-7 years: 5
- 8-39 years: 4
- 40-59 years: 2
- Over 60: 1
The disadvantage of the Beighton score is that it's limited to those nine particular joints and doesn't test your shoulders or ankles.
If you do score high, or have cranky shoulders or ankles, remember that it's pretty harmless, but have a chat with your physiotherapist.
Keeping active and getting strong is important, but do it sensibly and recruit a personal trainer or physio to help you build your end-range strength.
Cassie White is a Sydney-based personal trainer, yoga coach and health journalist.
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