Sports Theory - Training & Muscle

Flexibility explained simply

Flexibility is the range of motion of a joint - how far you get before it stops. But that stop rarely comes from a muscle being too short. Most of the time your nervous system is applying the brake to protect you.

Range = joint shape + muscle length + protective tension Only the last two can be trained
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You cannot change how a joint is built. A knee is a hinge and will never become a ball joint. Everything else is a matter of practice.

💬 Mia & Grandpa Theo

Mia

Why do I reach much further in the evening than in the morning?

Grandpa Theo

Because warm tissue gives more easily, and by the evening your nervous system has already seen movement. In the morning the safety brake is pulled tighter.

Mia

So stretching does not make me longer, only braver?

Grandpa Theo

Exactly that, at least at first. You teach your nervous system that the new position is harmless, and it releases the brake. Only with very long, regular stretching does the tissue itself change.

That is why warming up works so reliably: it changes nothing about the muscle, but it calms the protective tension.

Fun Fact

Every joint is a lever. Your tendons attach very close to the pivot - the biceps pulls only about four centimetres from the elbow. That costs an enormous amount of force, but it buys speed: a small shortening of the muscle becomes a wide, fast movement of the hand.

This text explains the basics of training and is not a substitute for individual training or medical advice.

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