I can predict your next ten years from your left heel.

I'm at JFK Terminal 4. Delta Sky Club. There's a man in seat 14, navy suit, expensive watch, eyes locked on a Bloomberg article about ten-year yields. His left heel is striking the floor approximately three times per second. He has been doing this for nine minutes without pause.

His coffee cup is rattling on the side table. He does not notice.

This is one of the most reliable behavioral patterns I read in airports, hospitals, courtrooms, and waiting rooms of every kind. I call it the leak. Because that's what it is — a literal venting of unburned adrenaline through the smallest convenient muscle group your nervous system can find.

The mirror.

Are you sitting still right now? Genuinely still? Or is one of your feet moving — a heel bounce, a toe tap, a knee swing? Is a finger drumming? Is your tongue moving against your teeth?

If something on your body is moving in a small, rhythmic, repetitive way and you can't remember starting it, congratulations: you've just caught your own leak.

The science.

The polite name for what the man in seat 14 is doing is non-exercise activity thermogenesis, or NEAT. Researchers at the Mayo Clinic originally identified it in the early 2000s as a metabolic curiosity — the small fidgety movements that distinguish thin people from heavy ones at the same caloric intake. That's the gym-floor version of the story.

There's another version, and it's the one I care about.

When you are under sustained stress — financial, relational, professional, ambient — your adrenal glands release adrenaline and your liver releases glucose into your bloodstream. This is the metabolic preparation for a physical response your evolutionary ancestors would have actually had: running, fighting, climbing. Modern life has stripped out the physical response but kept the chemical preparation intact. You are sitting in a leather lounge chair at JFK with the bloodstream of a man being chased by a wolf.

Your body does not tolerate that mismatch indefinitely. The unburned glucose has to go somewhere. The unspent adrenaline has to discharge somewhere. So your nervous system improvises, routing the excess down the longest, most readily available muscle chain — usually the leg — and burning it off three heel-strikes at a time.

The bounce isn't a habit. It's a symptom. It's the metabolic equivalent of a faucet that won't shut all the way off.

Why it matters past forty-five: chronic unresolved sympathetic activation is one of the most reliable predictors of cardiovascular events in the next decade. The leak isn't dangerous. The pressure behind it is.

The prescription: The 3-Minute Foot Grounding.

This is the somatic intervention I use myself, and it works precisely because it gives the nervous system the information it isn't getting from the heel bounce — namely, that the threat is over and the ground is solid.

Sit. Both feet flat on the floor, shoes off if you can manage it. Press the four corners of each foot — the ball under the big toe, the ball under the little toe, the inside heel, the outside heel — slowly into the ground, one corner at a time. Hold each for five seconds. You should feel small involuntary adjustments in your hips and lower back as your body recalibrates.

Then sit still. Breathe normally. Notice that, for the first time in possibly several hours, nothing on you is moving.

Three minutes. That's it.

The mechanism is simple: deep pressure through the soles of the feet activates the same proprioceptive feedback loops your nervous system evolved to use as safety signals — am I on stable ground, am I oriented, can I rest? The bounce, paradoxically, was your body asking that exact question and not getting an answer.

Field note.

The next time you catch yourself bouncing in public, don't stop it. Watch it. How fast is the rhythm? Which leg? Did it start when you sat down, or when you opened an email? The pattern will tell you what you're actually anxious about.

Then ground your feet.

— Julian Vance (J.), Your Health Profiler