The full recovery, start to finish

Acute spasms typically start easing within three to seven days. Full resolution is often seven to ten days and sometimes longer. Recovery varies a lot between people, and between episodes in the same person. The first 72 hours are usually the worst of it. The exact day-by-day actions — what changes on day 4 versus day 7, the specific ball placements, when walking starts and for how long — are laid out fully in the protocol.

What's actually happening in there

This isn't weakness and it isn't poor flexibility. It's a protective reflex called muscle guarding, and it runs at the level of the spinal cord, mostly without the brain's involvement.

Pain and stretch sensors detect something they read as damage — an irritated disc, a joint under strain, a ligament pushed past its range. They fire into the spinal cord. The cord answers by driving the gamma motor neurons, which tighten the muscle spindles inside the muscle. Now the spindles are more sensitive, so any movement reads as more danger, so the cord clamps harder. That's the loop, and it's why you can't think or stretch your way out of it.

Normally when one muscle contracts its opposite relaxes. During a spasm that reciprocal inhibition breaks down and both sides fire at once, which is why the segment feels like concrete rather than like a cramp pulling in one direction.

The sustained contraction then squeezes its own blood supply shut. Less oxygen, metabolic waste building up, more irritation of the pain sensors, more spasm. Spasm, ischemia, pain, spasm.

If this keeps happening

Repeat spasms tell you something. Usually one of three things:

• The alarm threshold has dropped. After enough episodes the spinal cord learns the pattern and fires it off from smaller and smaller triggers. A sneeze, a sock, reaching for a kettle. That's central sensitisation, and it's real physiology, not imagination.
• Something underneath feels unstable. A disc that shifts in certain positions, ligament laxity from an old injury, deep stabilisers that aren't doing their share so the big superficial muscles take over and stay switched on.
• Load and life. Sustained stress keeps the sympathetic system up, which lowers the threshold for guarding. Poor sleep does the same. So does sitting for nine hours and then lifting something at an angle.

The spasm is protection. The useful question is never "how do I stop the spasm" — it's what is my nervous system protecting me from.

When to get assessed

Beyond the emergency warning signs, book an appointment if:

• This is your first severe spasm and you've never had the area looked at
• There's no improvement at all after five to seven days of proper rest
• Symptoms are getting worse at any point
• Pain radiates down the leg below the knee
• You have numbness, pins and needles or weakness in a leg
• Spasms are recurring, or you need muscle relaxants more than three or four times a year

Worth asking for: physiotherapy, ideally someone who works with pain neuroscience rather than only exercises; imaging if the picture warrants it; an osteopathic, chiropractic or orthopaedic assessment; a pain specialist if this has been going on for years.