If you took the advice to stand more and really committed, you might now be on your feet for most of the day, with legs and a lower back that are starting to protest. It is a very understandable place to land. The thing worth knowing is that standing is not automatically better than sitting. Like most things, it is the balance that does you good, not the extreme.

Your calves work like a second heart

Here is a nice bit of the body's design. Every time your calf muscles contract as you move, they squeeze blood and fluid back up out of your legs towards your heart, which is why they are sometimes called a second heart. Stand still for a long stretch and that pump goes quiet. Fluid starts to settle in your lower legs and feet, which is why they can feel heavy, puffy or achy by the afternoon. The fix is not to sit down, it is to keep the calves moving, because movement is what switches the pump back on.

Standing still loads you too

Holding one standing shape for hours has its own cost, just as sitting does. Reviews of prolonged standing link long, static spells with aching legs and lower back discomfort, even in people who are perfectly fit. The common thread with sitting is stillness. Your body is not really asking you to stand or to sit, it is asking you not to stay frozen in either one for too long.

How much is worth aiming for

If you have swung from sitting all day to standing most of it, easing back towards a mix will usually feel a lot better. Guidance tends to point towards a couple of hours of standing spread across the working day rather than four, five or more in one go. Building up gently, and letting standing be one part of your day rather than the whole of it, is kinder to your legs and back than going all in.

Keep the pump working while you stand

When you are up, a few small things keep things comfortable. You could try shifting your weight from foot to foot, resting one foot on a low footrest and swapping every so often, or taking a few steps whenever you think of it. Letting your knees stay soft rather than locked keeps everything a little more relaxed. And sitting for part of the day is not backsliding, it is the other half of the balance.

A quick checklist to get going

• Aim to mix sitting and standing rather than standing for hours on end.
• Keep your calves working with small steps and weight shifts while you stand.
• Build standing up gradually, towards a couple of hours spread across the day.
• Use a footrest and a soft mat, and keep your knees soft rather than locked.
• Notice heavy or achy legs as a cue to move, not just to sit.

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