Advertisement
What happens inside a muscle when it cramps
19th July, 2026 02:43 PM
Almost everyone has experienced it. Whether you are running to catch a matatu, playing a weekend football match, or turning in bed at night, a sudden muscle cramp can leave you completely helpless.
It feels like your muscle is violently twisting into a hard knot, causing sharp, immediate pain. While most people blame dehydration or a lack of salt, sports scientists are discovering that the true culprit is a sudden misfire in your nervous system.
Why your muscles suddenly lock up
For a long time, the go-to explanation for muscle cramps was dehydration and lost electrolytes. The idea made sense: when you sweat heavily, you lose essential salts like sodium and potassium, causing your muscle fibres to twitch and lock up.
However, modern research shows that cramps frequently happen even in cold weather where people barely sweat.
Scientists point to what they call altered neuromuscular control. This means muscle fatigue disrupts the way your nerves and muscles talk to each other.
Inside your muscle, specialised structures called muscle spindles tell the muscle to contract, while Golgi tendon organs tell it to relax. When a muscle gets exhausted, this system breaks down.
According to a peer-reviewed study published in Materia Socio Medica, “Muscle overload and fatigue affects the balance between the excitatory drive from muscle spindles and the inhibitory drive from the GTO.”
This imbalance forces your spinal cord to send continuous, uncontrolled electrical signals, locking the muscle into a painful knot.
How to stop and prevent the pain
The quickest way to stop a cramp in its tracks is forceful, passive stretching.
Stretching pulls the muscle straight, which forces the Golgi tendon organs to wake up. These organs then signal the spinal cord to turn off the chaotic electrical signals, allowing the muscle to relax immediately.
Another surprising remedy involves tricking your nervous system through your mouth. Drinking strong, pungent liquids like pickle juice or a spicy fluid triggers specialised nerve receptors in your throat. This action sends a rapid reflex down your spinal cord that interrupts and dampens the overactive nerve signals causing the cramp.
To keep cramps from coming back, building muscle endurance is far more effective than just taking sports drinks. Gradually increasing your exercise intensity gives your nervous system time to adapt without getting overwhelmed.
Consistent rest and simple daily stretching remain the most reliable ways to keep your muscles moving smoothly.
