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A name that is probably wrong

Do Growing Pains Really Come From Growing?

Bones grow at a rate you could never feel, and the aches that carry the name almost certainly come from something else.

Growth happens atplates near the endsA few centimetres ayear, at mostThat is far too slow tofeelYet the aches are real
The aches are real. The explanation in the name is not.
  1. Step 1 of 5

    Bones lengthen at plates near their ends.

    A long bone A growth plate near eachend

    A layer of cartilage sits near each end, makes new cartilage on one side and turns to bone on the other. The bone grows from there, not in the middle.

  2. Step 2 of 5

    The rate is far too slow to feel.

    A growth spurtabout 6 cm ayearPer dayroughly 17micrometres

    Even a fast-growing child adds around 6 cm a year — about 17 micrometres a day, roughly a fifth the width of a hair. Nothing could register that.

  3. Step 3 of 5

    And the aches are in the wrong place.

    Where growth happens At the ends of the boneWhere it aches In the muscle, bothlegs

    They are typically in muscles — the front of the thigh, the calf, behind the knee — not at the growth plates, and both legs at once.

  4. Step 4 of 5

    They come in the evening after busy days.

    1 A busy day2 Aching in theevening3 Gone by morning

    The strongest pattern is time, not height: late afternoon and evening, after a day of running about, and gone entirely by morning.

  5. Step 5 of 5

    Overuse fits the evidence far better.

    Muscles workedhard all day Warmth and rubbinghelp — as with anyache

    Tired muscles after hard use explain the timing, the location and the fact that rubbing and warmth help — which is what you would do for any muscle ache.

    Pain that wakes a child, sticks to one leg, or is still there in the morning does not fit this pattern at all, and is worth a doctor's opinion.

The short version

Bones grow a few micrometres a day, which nobody could feel — so growing pains are real aches with a name that points at the wrong cause.

Try it yourself

Mark a height on a doorframe and check again in a month. A few millimetres is a lot of growing, and nobody feels a millimetre.

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