Flexibility Is Overrated. Here's What Actually Matters.

A deep dive into the difference between flexibility and mobility — and why chasing range of motion might be getting in your way.

The myth we inherited

For decades, the fitness world told us a simple story: stretch more, move better, get hurt less. Warm up with a hamstring stretch. Cool down with a quad stretch. Touch your toes. Open your hips. The more flexible you are, the healthier your body is.

It's a good story. Clean, logical, easy to teach. But it's not quite the full picture.

What the evidence actually says

Stretching does one thing very reliably: it increases range of motion. On that, the science is consistent. But when researchers looked at whether that range of motion translates to fewer injuries or less post-workout soreness, the results were far less convincing.

A 2014 review evaluating over 26,000 people found that improved strength reduced injury risk by nearly 70% and better balance by 35% — while stretching, regardless of type, showed no significant injury reduction at all. A 2025 Delphi consensus statement involving international research experts concluded that stretching "does not serve as an all-encompassing injury prevention strategy" and doesn't meaningfully reduce muscle soreness after exercise.

A 2004 paper in a clinical journal put it plainly: "little or no scientific evidence supports the practice [of stretching to prevent injury], and recent research suggests that stretching which increases flexibility beyond that needed for sport-specific movements may cause injury."

This isn't an argument against stretching. It's an argument for understanding what stretching is actually for.

The key distinction: flexibility ≠ mobility

Flexibility is passive range of motion — how far a joint or muscle can be moved, with or without assistance. It's a tissue property.

Mobility is something richer: it's the active, controlled use of that range. It includes flexibility, but also requires muscular strength, joint stability, and neuromotor coordination. You can think of it as range of motion that you own — not just range that your body passively has.

Blandine Calais-Germain, in Anatomy of Movement, draws a similar distinction when discussing the three types of movement exercise: flexibilisation (recovering range), strengthening (force through movement), and movement coordination (motor control and neuromuscular refinement). These three are distinct, and all three matter.

The sports science literature agrees: as one framework puts it, Mobility = Flexibility + Active Stability. Passive range without active control doesn't improve how you move — it just means your joints can travel further without your nervous system fully managing the journey.

Why more range isn't always more

Here's the counterintuitive part: excessive flexibility without control can actually compromise movement quality.

When we pursue range of motion as the goal — pushing further into a stretch, accumulating more "openness" — we can increase range while decreasing stability. And an unstable body doesn't move better. It protects itself. The nervous system reads instability as a threat and restricts movement in response. This is why many hypermobile people, who can achieve extreme ranges, often report feeling tight or restricted: their nervous system is actively limiting access to ranges it can't control.

There's also a biomechanical argument for some degree of muscular tension. The muscle-tendon unit functions as a biological spring: it stores elastic energy during loading and releases it during movement. A muscle with appropriate tension is more efficient at this storage and release cycle, requiring less metabolic energy to stabilise and move. Excessive passive flexibility can interfere with this spring-like quality.

This doesn't mean rigidity is the goal. Chronic stiffness that genuinely limits functional movement — not being able to reach your feet without bending your knees, restricted hip mobility that changes how you walk — does increase injury risk and deserves attention. The point is that balance is the target, not maximum range.

What Pilates actually trains

Pilates is often marketed as a stretching practice. This is a misread.

What Pilates trains — at its core — is the capacity to move with control through range. Every exercise asks you to be both mobile and stable simultaneously: to access length while maintaining support. That's not stretching. That's coordination, strength, and motor control expressed through movement.

In Calais-Germain's framework, this maps closely to movement coordination exercise — developing the neuromotor patterns that allow your muscles to participate elegantly in complex chains of movement. The goal isn't to lengthen a hamstring in isolation. It's to teach the whole system — pelvis, spine, legs, breath — to move together with efficiency and control.

Flexibility is a tool in that process. Not the destination.

In short

• Flexibility = passive range. Useful, but incomplete.

• Mobility = range + control + stability. This is what actually improves movement.

• Stretching increases range of motion. It doesn't reliably prevent injury or reduce soreness on its own.

• A body with some tension moves more efficiently than one with no tension at all.

• Chronic rigidity that limits function is worth addressing. Extreme range without control is not the solution.

• The goal is to move better — not to move further.

References

• Calais-Germain, B. (1994). Anatomy of Movement. Eastland Press. (Spanish ed.: Anatomía para el movimiento)

• Afonso, J. et al. (2025). "Practical recommendations on stretching exercise: A Delphi consensus statement of international research experts." Journal of Sport and Health Science. ScienceDirect. https://doi.org/10.1016/j.jshs.2025.01.003

• Shrier, I. (2004). "The role of flexibility in injury prevention and athletic performance: have we stretched the truth?" Clinical Journal of Sport Medicine [via PubMed]. https://pubmed.ncbi.nlm.nih.gov/15495679/

• Lauersen, J.B. et al. (2014). "The effectiveness of exercise interventions to prevent sports injuries." British Journal of Sports Medicine, 48(11), 871–877.

• Ikeda, N. et al. (2025). "Effects of post-exercise stretching versus no stretching on lower limb muscle recovery and performance: a meta-analysis." Frontiers in Physiology. https://doi.org/10.3389/fphys.2025.1674871

• Nuzzo, J.L. et al. (2024). "Strength Training versus Stretching for Improving Range of Motion." International Journal of Exercise Science [via PMC]. https://pmc.ncbi.nlm.nih.gov/articles/PMC8067745/

• Page, P. (2012). "Current concepts in muscle stretching for exercise and rehabilitation." International Journal of Sports Physical Therapy, 7(1), 109–119.

• Humano Performance (2020). "Mobility vs. Stability (vs. Flexibility)." https://humanoperformance.com

• Telos Strength & Conditioning. "Mobility. Flexibility. Stability." https://telosstrength.com