Three things happen at once. Red and near-infrared LEDs sit against the joint and the light is absorbed by the tissue beneath the skin, where it supports local circulation. At the same time the unit warms the whole knee, which loosens the muscle and connective tissue around it. Underneath that, low-frequency vibration works through the surrounding area.

Fifteen minutes, once a day. Most people use it in the evening in front of the TV, or first thing if mornings are the worst part.

KneeVive is built for stiff, aching, worn-out knees — the kind that seize up in the morning, complain on the stairs, or ache after a long day on your feet. That covers osteoarthritis, general wear and tear, old sports injuries and knees that have simply done a lot of miles.

Most people feel the knee loosen after the first few sessions. The change worth having comes from daily use over six to eight weeks.

If your knee pain came on suddenly, follows a recent injury, or you've got reduced sensation in the area, speak to your GP before using it.

Every day. Fifteen minutes. That's the whole routine, and consistency beats intensity every time.

Start on the lowest heat and vibration setting for your first few sessions and work up once you know how your knee responds. Sit somewhere you'll stay put — the unit is cordless, so the sofa is fine.

If both knees give you trouble, do both. Alternate days if you've only got one unit.

Give it eight weeks before you decide. The first fortnight tells you whether it feels good; week eight tells you whether it's worth keeping up.

Free UK delivery on all orders. Dispatched within 5 working days arriving in 10 working days. Tracking emailed as soon as it ships.

Not for you? Send it back within 30 days for a full refund. Email kneevive@outlook.com and we'll sort it.