4.12 Active and Passive Mobility

The short version

There are two kinds of flexibility. Passive range is how far your body can go when something else moves it - like a partner pushing your leg, or you pulling it with your hands. Active range is how far you can move using only your own muscles. For almost everyone, the active number is smaller.

Sport only cares about the range you can control on your own. So the goal is not more stretching - it is closing the gap between the two numbers. You do that in steps: hold your end positions with your own strength, then slowly add weight and speed. Flexibility you cannot control does not show up on the field.

Executive summary. Passive mobility is the range an external force can move you into. Active mobility is the range you can produce yourself. Almost all flexibility testing measures the first, almost all performance depends on the second, and the difference between them is the most informative and least collected number in mobility assessment. This article explains why the gap exists, breaks down the three distinct causes, sets out a four-stage progression for converting passive range into active range, and explains why an athlete with a large gap should generally stop stretching and start loading. It also covers the specific case of hypermobility, where the gap is largest and the conventional advice is most harmful.

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Key takeaways

1. Passive range is what someone else can move you into. Active range is what you can produce yourself. Only the second one is usable.
2. The gap between those two numbers is the most actionable measurement in a mobility assessment — and almost nobody collects it.
3. A large gap has three distinct causes: weakness of the shortening muscle, weakness of the lengthening muscle, or control and confidence factors.
4. Stretching raises passive range and does little for active range. So an athlete with a large gap who stretches more is widening it.
5. Converting passive range into active range takes end-range strength work, progressed by removing external assistance in stages.
6. Hypermobile people have the largest gaps of anyone — and benefit least from more passive range work.

The test that changes the answer

Here's a two-minute experiment that will quietly reorganise how you think about flexibility. Lie on your back. Keeping the knee straight, lift one leg as high as you can using only your own effort, and have someone note the angle.

Now relax completely and let them push that same leg as far as it will comfortably go. Note that angle too.

For a large proportion of people, the second number is twenty to forty degrees higher than the first. Read that again — twenty to forty degrees.

That difference is not a measurement error. It's range that exists, that your tissue happily permits, and that you cannot access on your own.

Think of it as money in an account you can't withdraw from. It's technically yours. It buys you nothing.

And here's the strange part: this gap is the most informative number in mobility assessment, and almost nobody ever measures it.

Think about how flexibility gets tested almost everywhere — someone or something moves you, and the biggest angle wins. Nearly all testing measures the passive number, while nearly all performance depends on the active one.

So the single most useful measurement in the whole field sits uncollected, one extra minute away from every test that's already being done.

Two kinds of range, two different animals

It's worth being precise about how these two qualities differ, because they differ on every dimension that matters.

• Definition. Passive mobility is range reached by an external force while your muscles stay relaxed. Active mobility is range reached by your own muscular effort. The second is what you can actually use.
• What limits it. Passive range is limited by tissue extensibility and stretch tolerance. Active range is limited by strength at short and long muscle lengths, plus motor control (Neumann, 2016). Different limiters need different interventions.
• How it's tested. Passive: a partner or gravity moves the limb while you relax. Active: you move the limb unaided against gravity. Testing only the first hides the problem.
• How it's trained. Passive: static stretching, proprioceptive neuromuscular facilitation (PNF), sustained end-range positions. Active: end-range isometrics, loaded mobility, active raises. Stretching does not develop active range.
• Typical value. Passive is the larger number, often much larger. Active is always the smaller one. The difference between them is the actionable measurement.
• Risk if excessive. Passive range you can't control is joint travel you can't govern — an instability risk. Excess active range carries very little risk, because it's inherently controlled.

Notice what that list keeps repeating: nothing about stretching appears anywhere in the active column. That's not an oversight — it's the finding.

In short: different qualities, different limiters, different training methods. Treating them as one number is why so many mobility programmes produce range that never appears in performance.

You can see the two qualities separated cleanly in sport. Gymnasts and dancers train active range as a matter of course — holding positions unaided rather than reaching them with assistance — which is why their gaps stay small despite enormous passive range.

Overhead athletes in swimming, throwing and volleyball often show the opposite: generous passive shoulder range with poor active control at end range. That combination is associated with shoulder problems, which tells you the gap isn't just a performance issue (Wilk, 2011).

Now apply it to a real case. Someone with one hundred degrees of passive hip flexion and sixty degrees of active hip flexion does not have a tissue length problem — their tissue clearly permits one hundred degrees.

What they lack is the ability to produce and control the movement. And stretching addresses none of that.

Worse: stretching will typically raise the passive number while leaving the active number unchanged, which widens the gap (Moreside & McGill, 2013). They become, by the usual measure, more flexible — and by the measure that matters, no better off.

That's a forty degree gap growing. Range they own on paper, and still can't spend.

Why performance depends on the active number

Think about what actually happens when you kick, sprint, throw or lift. No external force is out there positioning your limbs for you.

Every degree of range you use is produced by your own muscles — against gravity, momentum and load. A passive range that only appears when someone else is pushing does not exist during the activity.

This is painfully visible in kicking sports, where the gap at the hip is often very large precisely because kicks get practised at ranges well inside passive capacity. The bendiest person in the room is not necessarily the highest kicker.

It's not only kicks, either. Field-sport athletes commonly carry their biggest gaps at the ankle, and an ankle gap quietly limits squat depth and deceleration mechanics.

And for older adults, the stakes are plainly practical: active range at the shoulder and hip is what decides whether reaching, dressing and stairs stay comfortable. Passive range decides none of that.

Four numbers worth keeping straight:

• Passive range of motion. Range achieved by external force with you relaxed. Limited by tissue extensibility and stretch tolerance. The number most flexibility tests report.
• Active range of motion. Range achieved by your own muscular effort. Limited additionally by strength at short muscle lengths and by motor control. Always the smaller number.
• The gap. Passive minus active. A small gap means well-controlled range. A large gap means range that exists but is unavailable — which makes it a strength problem, not a flexibility one.
• Functional range. What survives under load, at speed and when fatigued. Smaller again than active range, and the only one that appears in competition.

This is also why so many mobility programmes fail to change how anyone actually moves. Twelve diligent weeks of increasing passive range, and none of it turns up in the squat, the sprint or the kick (Moreside & McGill, 2013).

Not because the range wasn't gained. Because none of it was ever converted.

Keep that word — converted. It's the job description for everything in the rest of this article, and it's a strength job, not a stretching one.

Three reasons for a gap — and three different fixes

Here's where most gap-closing efforts go sideways: a gap is not one problem with one solution.

Correctly identifying which cause applies is the difference between a productive block and a wasted one. There are three branches.

Before we walk them: the whole assessment really compresses into one question — can you get there without help? Everything below is about why the answer is no, and what to do about it.

Cause one: the shortening muscle is weak. The muscle that produces the movement can't contract hard enough in its shortest range. This is the most common cause — and the most commonly missed.

Make it concrete. To lift your leg to one hundred degrees of hip flexion, your hip flexors must contract while already very short, which is mechanically their weakest position. Many people simply cannot generate enough force there, regardless of how extensible their hamstrings are.

The classic picture is hip flexors too weak to raise the leg to the height a partner can move it to. The fix: active raises, isometric holds at the top of the range, and loaded work in that shortened position.

Cause two: the lengthening muscle is weak. The opposing muscle can't control its own long-range position — and your nervous system knows it.

The system is reluctant to allow a joint into a range it cannot safely decelerate out of. If your hamstrings can't control themselves at long length, active hip flexion gets limited as a protective measure, and it will keep being limited until that capacity exists.

The fix here is eccentric and long-length isometric work for the opposing muscle (Lindstedt et al., 2001; Alonso-Fernandez, 2018). This cause turns up often at the hamstrings and adductors in field-sport athletes.

Cause three: control and confidence. Sometimes the pattern has simply never been practised actively. Sometimes a prior injury has produced protective guarding at a specific range, or fear and the expectation of pain limit voluntary effort.

These respond to graded, unthreatening exposure more than to strength work alone. You're not building tissue here — you're renegotiating with a nervous system that has its reasons.

One-line recap: weak lifter, train the top. Weak brakes, train the brakes. Wary system, expose it gently.

A quick differentiator: If the athlete can hold the end position when placed there but cannot get there themselves, the problem is the shortening muscle. If they cannot even hold the position once placed there, the problem is more likely control or opposing-muscle capacity.

That little test sorts most cases in under a minute. Run it before you programme anything.

Converting range you have into range you can use

The four-stage conversion

The principle is almost embarrassingly simple: begin in the end position with as much help as you need, then systematically remove the help.

Here's the ladder, stage by stage.

Stage one — passive positioning. Reach the end position with external help: a strap, a wall, a partner, or gravity. Hold, and simply get familiar with being there. No strength demand yet — the goal is exposure and tolerance.

Stage two — assisted isometric. Same supported position, but now contract into the end range at low intensity for ten to twenty seconds. The support is still there; the difference is that you're producing tension where you previously only received a stretch.

Stage three — unassisted hold. Remove the support and hold the position using nothing but your own muscular effort. Expect the achievable range to drop substantially at first. That drop is the gap made visible.

Stage four — loaded and dynamic. Add external load, then speed. Weighted leg raises, loaded end-range holds, and finally the movement performed dynamically. At this point the range is genuinely owned, and it stops disappearing under fatigue.

The value of this sequence is what it never does. It never asks you to produce force in a position you can't yet reach, and it never leaves you passively parked in a position you can't yet control.

Each stage bridges the previous one. No leaps of faith required.

The working numbers:

1. Stage one: reach the end position with a strap, a wall, a partner or gravity. Hold for 30 to 60 seconds. No effort required.
2. Stage two: in the same supported position, contract into the end range at 20 to 30 per cent effort for 10 to 20 seconds. Repeat three to five times.
3. Stage three: remove the support entirely and hold the position unaided. Expect a large drop in achievable range at first.
4. Stage four: add external load, then speed. Ankle weights, cables, or your own bodyweight in a more demanding position.

A word of reassurance about stage three, because it's where people wobble. The sudden loss of range when the support leaves isn't regression — it's the honest measurement finally showing itself, and it narrows steadily as the holds accumulate.

Want it even more concrete? Take that straight-leg raise from the top of the article. Stage one: hold the leg up with a strap. Stage two: press gently into the strap at 20 to 30 per cent effort. Stage three: take the strap away and hold. Stage four: add an ankle weight, then raise the leg with speed and control.

The progression criterion between stages is quality, not time. Move on when you can hold the current stage for the target duration without trembling, without losing position and without compensating elsewhere.

About that trembling: it's informative rather than alarming. It means the position is genuinely challenging — and it should resolve within a few weeks.

End-range isometrics: the primary tool

If you keep only one exercise category from this article, keep this one. The end-range isometric: hold the joint at or near its limit, and produce tension there.

The rationale is joint-angle specificity. Strength adaptations from isometric training are largest at or near the trained joint angle, and the carryover shrinks as you move away from it (Kitai & Sale, 1989; Noorkoiv et al., 2014).

Your problem is specifically an inability to produce force at end range. So you train at end range. The direct solution, no cleverness required.

Four variations, in rough order of progression:

• End-range isometric hold. Hold the joint at its active limit against gravity or light resistance. Ten to thirty seconds, three to five repetitions. The foundational method.
• Passive-to-active transition. Enter the position passively, then remove the support and try to hold. The moment the support leaves is the training stimulus — and the range that disappears is the gap.
• Loaded end-range hold. The same hold with external load added. Progresses the stimulus once the unloaded version feels comfortable.
• End-range dynamic work. Small-amplitude repetitions performed at the outer limit rather than through the mid-range. Bridges holding capacity into movement capacity.

The beauty of the basic hold is its economy. It targets the exact deficit, needs no equipment, and works at any joint — everything else in this area is a variation on it.

The governing principle is worth pinning to the wall: own it before you extend it.

Why do these holds make you shake? Because you're producing force in a position where you have very little capacity, so motor unit recruitment is unsteady. Shaking is a reasonable sign you've found genuine end range rather than a comfortable approximation.

Volume requirements are modest: two or three exercises, three to five holds each, three to four times a week. That's a realistic and effective dose.

One honest warning. This work is fatiguing in a way that's easy to underestimate, particularly in the first fortnight. Plan for it rather than being ambushed by it.

Active and passive insufficiency: when the limit is mechanical

Two anatomical concepts explain some gaps that would otherwise look like weakness. They cannot be trained away, because they're mechanical.

Active insufficiency happens when a muscle crossing two joints is asked to shorten across both at the same time. At that point it cannot generate meaningful force (Neumann, 2016).

Your hamstrings cross the hip and the knee. Try to flex the knee fully while the hip is also extended, and they land in a position where they simply cannot contract effectively. That is not weakness, and it does not improve with training.

Passive insufficiency is the mirror image: a two-joint muscle is lengthened across both joints simultaneously and reaches its limit before either joint reaches its own.

Straight-leg hip flexion is restricted by the hamstrings crossing both joints — which is exactly why the same movement with a bent knee produces far more hip flexion (Kendall, 2005).

How to spot them in the wild:

• If a range restriction disappears when you change the position of the adjacent joint, you're looking at passive insufficiency rather than a joint restriction.
• If force production collapses at one specific combined position, suspect active insufficiency rather than weakness.
• Neither is trainable in the conventional sense. Both are managed by choosing positions that account for them.
• Testing hip flexion with a bent knee and a straight knee separately distinguishes hamstring restriction from hip joint restriction in about ten seconds.

This matters more than it sounds. A lot of apparent mobility restrictions dissolve the moment the adjacent joint is repositioned.

It's also why someone can sit comfortably in a deep squat, knees bent, yet look hopelessly restricted on a straight-leg test. Same hips, different hamstring length demand.

Recognising that saves an athlete months of stretching something that was never the limit. Ten seconds of testing versus a season of wasted stretching — cheap insurance.

The hypermobile case

People with generalised hypermobility have the largest active-passive gaps of any group (Simmonds & Keer, 2007). They also receive the least appropriate advice.

The typical loop runs like this. Abundant passive range, yet a persistent feeling of stiffness. So they stretch for relief — and feel better, briefly.

Within hours, the stiffness is back. Conclusion: must stretch more. And around it goes — one of the more reliably counterproductive loops in the field.

Here's the catch: the stiffness sensation in this population is generally not a tissue length problem at all. It appears to relate to muscular effort spent stabilising joints that have insufficient passive restraint (Simmonds & Keer, 2007).

Stretch those muscles and you reduce the stabilisation temporarily, which feels like relief. Then the underlying situation reasserts itself, right on schedule.

None of which means the stretching time was wasted effort — it just needs redirecting. The minutes go into end-range isometrics and loaded work through range instead, where they'll actually move the problem.

The playbook for this group is lift, not lengthen:

1. Stop adding passive range. It is not the limiting factor, and it worsens the underlying situation.
2. Prioritise strength work, particularly in the mid-range and inner range where hypermobile joints are least well controlled (Palmer, 2014).
3. Use end-range isometrics to build active control at the outer limits that already exist.
4. Progress load slowly, since connective tissue tolerance may be lower.
5. Seek clinical assessment where hypermobility comes with pain, frequent subluxation or other systemic features — some presentations warrant specific medical management (Simmonds & Keer, 2007).

This is not an argument that hypermobile people should never stretch. It is an argument that for this group, the default intervention should be strength through range, and that persistent stretching without strength work tends to entrench the problem.

Testing and tracking the gap

The measurement itself is easy. The discipline that makes it useful is the same as for any range measurement: standardise everything.

Here's what success looks like when you plot it. Over twelve weeks of end-range strength work, the passive line holds roughly steady while the active line rises to meet it — the gap closing from below.

That's the goal of most mobility work in one image: raise the lower line, not the upper one. An athlete with a forty degree gap does not need more range — they need to own the range they already have.

One rule above all: test active first, always. Testing passive first stretches the tissue and raises the subsequent active measurement, which contaminates the comparison (Norkin & White, 2016).

So the order is fixed: active, rest briefly, then passive. Every time.

Standard positions worth using:

• Hip flexion: supine straight-leg raise, active then passive, opposite leg held flat.
• Hip extension: prone, active then passive, pelvis stabilised.
• Shoulder flexion: supine with the lumbar spine flat against the floor, which prevents compensation.
• Shoulder external rotation: supine at 90 degrees of abduction, elbow supported.
• Ankle dorsiflexion: knee-to-wall test for passive, active heel-down dorsiflexion for active.

When is a gap worth chasing? A gap of roughly ten to fifteen degrees at a major joint is normal and expected — everyone carries some difference between the two numbers.

More than about fifteen to twenty degrees, though, and there's meaningful range you cannot access. That deserves a dedicated intervention; below it, the difference doesn't warrant one.

Standardising matters because the gap you're tracking can be smaller than the noise from sloppy testing. Same position, same order, same time in the session — then the trend means something.

Track it every six weeks on the same protocol. Expect the active number to move while the passive number stays largely still — that's the pattern you're after, not a rising passive score.

An eight-week gap-closing block

This block is written for an athlete with adequate passive range and a gap of twenty degrees or more at one or two joints.

If passive range is genuinely insufficient, address that first with the methods in the static stretching article. Then come back and run this.

Set your expectations before you start. Closing a gap takes six to twelve weeks of consistent end-range work — often longer for a very large gap — and it feels slower than the quick early wins stretching hands out.

That slowness is the honest price of gains that actually last. Here's the plan.

Weeks one and two: exposure and assisted work

Stages one and two of the ladder. You're buying familiarity and early tension, nothing heroic.

• Assessment: measure active and passive at the target joints, active first.
• Stage-one holds: 3 by 45 seconds in the supported end position, daily.
• Stage-two assisted isometrics: 4 by 15 seconds at low effort, four days per week.
• No stretching volume added. The passive number is already sufficient.

Weeks three to five: unassisted holds

The support comes away, and the gap shows itself. Hold your nerve.

• Stage-three unassisted end-range holds: 4 by 15 to 20 seconds, four days per week.
• Expect the achievable range to be much lower than the assisted version. This is the point, not a failure.
• Add small-amplitude repetitions at end range: 3 by 8, performed slowly.
• Remeasure at the end of week five.

Weeks six to eight: loading and speed

Now the new range earns its keep under load and at pace.

• Loaded end-range holds with ankle weights or light cable resistance: 4 by 12 seconds.
• Dynamic active raises through full range: 3 by 8 with control at the top.
• Integrate the work into the training session rather than performing it separately.
• Final measurement at week eight, active and passive.

Interpreting the result

1. Active rose, passive stayed level, gap narrowed: exactly right. Move to maintenance.
2. Active rose slightly, gap still large: continue for another block. This is often slow work.
3. Neither moved: check the work is genuinely at end range, since most people perform it comfortably inside their limit.
4. Active rose and passive fell slightly: entirely acceptable. Usable range increased, which is the point.

Whatever your outcome, resist the urge to celebrate by stopping. The gain was built by producing force at end range, and it's kept the same way.

Maintenance afterwards is inexpensive, and worth taking seriously because active range detrains. Two sessions a week of end-range isometrics — or simply keeping full-range loaded exercise in the programme — will generally hold the gain.

Sport applications

Kicking athletes in martial arts and football need active hip flexion at speed, and the gap at this joint is often very large because kicks are usually practised at ranges well inside passive capacity.

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Gymnasts and dancers train active range as a matter of course, which is why their gaps are typically small despite very large passive ranges. Their approach, holding positions unaided rather than reaching them with assistance, is the model.

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Overhead athletes in swimming, throwing and volleyball frequently have generous passive shoulder range with poor active control at end range, and this combination is associated with shoulder problems (Wilk, 2011).

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Field-sport athletes usually have small gaps at the hip and larger ones at the ankle and thoracic spine, and the ankle gap in particular limits squat depth and deceleration mechanics.

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Older adults benefit substantially from closing gaps at the shoulder and hip, since active range determines whether reaching, dressing and stair use remain comfortable, and passive range does not.

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Common mistakes

• Only measuring passive range. It produces the bigger number and hides the actual problem. Measure both, always, and always measure active first.
• Stretching to fix a large gap. Stretching raises passive range and leaves active range largely unchanged, which widens the gap. The intervention needed is end-range strength work.
• Testing passive before active. Testing passive first stretches the tissue and inflates the subsequent active measurement, contaminating the comparison.
• Working inside the actual end range. Most people perform end-range work comfortably within their limit. If it does not feel precarious and produce trembling, it is probably not at end range.
• Mistaking passive insufficiency for joint restriction. If the restriction disappears when you reposition the adjacent joint, a two-joint muscle was the limit, not the joint. Test with the neighbouring joint in two positions.
• Advising hypermobile people to stretch more. They have abundant passive range already. The stiffness sensation usually reflects stabilisation effort, and stretching entrenches the problem while providing brief relief.
• Expecting fast results. Closing a gap takes six to twelve weeks of consistent end-range work. It is slower than the apparent gains from stretching, and more durable.
• Stopping once the gap closes. Active range detrains. Maintenance is cheap, roughly two sessions a week, or simply training through full range in normal exercise.

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Coaching cues

• "Can you get there without help?" is the whole assessment in one question.
• "Hold it where it shakes" to find genuine end range.
• "Own it before you extend it."
• "Active first, then passive" for testing order.
• "Take the strap away" as the transition to stage three.
• "Small range, high effort" for end-range work.
• "Bend the knee and check again" to test for passive insufficiency.
• "If you are hypermobile, lift rather than lengthen."

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FAQs

What is a normal gap between active and passive range?

A gap of roughly ten to fifteen degrees at a major joint is expected and does not need addressing. Beyond fifteen to twenty degrees, there is meaningful range the athlete cannot access, and that is worth a dedicated block of end-range work.

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Why can someone push my leg higher than I can lift it?

Because different things limit the two movements. Passive range is limited by tissue extensibility and stretch tolerance. Active range is additionally limited by how much force the muscle producing the movement can generate in its shortest position, and by whether the opposing muscle can control the end range. The tissue permits the range; your muscles cannot produce it.

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Should I stop stretching if my gap is large?

For that joint, largely yes. Your passive range is already sufficient, and adding to it widens the gap. Redirect the time into end-range isometrics and loaded work through range. You can keep light stretching as a warm-up if you find it useful, but it should not be the focus.

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How long does it take to close a gap?

Six to twelve weeks of consistent work for a meaningful change, and often longer for a very large gap. This is slower than the apparent improvements from stretching, which is one reason people abandon it. The gains are considerably more durable.

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What is the best single exercise for active range?

The end-range isometric hold: Reach the position with assistance, remove the assistance, and hold using your own effort. It targets the exact deficit, requires no equipment, and can be applied at any joint. Everything else in this area is a variation on it.

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Why do I shake during end-range holds?

Because you are producing force in a position where you have little capacity, and motor unit recruitment is unsteady as a result. It is a reasonable indicator that you have found genuine end range rather than a comfortable approximation, and it typically settles within a few weeks.

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Is a large gap dangerous?

It is not dangerous in itself, but passive range that cannot be actively controlled means joint travel the athlete cannot govern, which is a plausible contributor to injury in sports that reach end range at speed. It is also, more simply, wasted range: You carry the tissue extensibility and get none of the benefit.

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I am hypermobile. Should I do any mobility work at all?

Yes, but the emphasis inverts. Strength work through range, including end-range isometrics, is the priority, and further passive range work is generally unhelpful. If hypermobility comes with pain, frequent joint subluxations or other systemic features, get a proper clinical assessment rather than self-managing, since some presentations need specific medical care.

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Recommended videos

Each video below was chosen because it covers a specific part of this article in more depth than text alone allows.

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Related reading on FitXplor

• 4.9 Understanding Range of Motion
• 4.11 Static Stretching
• 4.1 Flexibility vs Mobility in Athletic Performance
• 4.5 The Hip: Mobility, Stability, and Power Transfer
• 4.6 The Shoulder Complex
• 4.2 The Joint-by-Joint Approach to Movement
• 3.14 Coordination and Motor Control
• 2.1 Principles of Strength Training

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References

Kendall, F.P. et al. (2005). Muscles: Testing and Function with Posture and Pain, 5th edition. Lippincott Williams & Wilkins.

Neumann, D.A. (2016). Kinesiology of the Musculoskeletal System, 3rd edition. Elsevier.

Norkin, C.C., White, D.J. (2016). Measurement of Joint Motion: A Guide to Goniometry, 5th edition. F.A. Davis.

Lindstedt, S.L., LaStayo, P.C., Reich, T.E. (2001). When active muscles lengthen: properties and consequences of eccentric contractions. News in Physiological Sciences.

Kitai, T.A., Sale, D.G. (1989). Specificity of joint angle in isometric training. European Journal of Applied Physiology.

Noorkoiv, M., Nosaka, K., Blazevich, A.J. (2014). Neuromuscular adaptations associated with knee joint angle-specific force change. Medicine & Science in Sports & Exercise.

Alonso-Fernandez, D. et al. (2018). Changes in muscle architecture of biceps femoris induced by eccentric strength training. Scandinavian Journal of Medicine & Science in Sports.

Simmonds, J.V., Keer, R.J. (2007). Hypermobility and the hypermobility syndrome. Manual Therapy.

Palmer, S. et al. (2014). The effectiveness of therapeutic exercise for joint hypermobility syndrome: a systematic review. Physiotherapy.

Wilk, K.E. et al. (2011). Shoulder injuries in the overhead athlete. Journal of Orthopaedic & Sports Physical Therapy.

Moreside, J.M., McGill, S.M. (2013). Improvements in hip flexibility do not transfer to mobility in functional movement patterns. Journal of Strength and Conditioning Research.

Behm, D.G. et al. (2021). Non-local muscle fatigue and stretching effects. Applied Physiology, Nutrition, and Metabolism.