Red Light Therapy Belt (Rødlysterapi-belte): Which Size?

It's mid-October and the light is already going by four. You get home, sink into the sofa under the pledd, and there it is again: the knee that complains on the stairs, or the lower back that has been quietly sore since August. You tell yourself you'll deal with it properly. Then the evening disappears, because anything you have to set up feels like one more job.

A red light therapy belt (rødlysterapi-belte) is a flexible LED pad that sits directly on your skin and delivers red and near-infrared light to one area, like a knee, shoulder or lower back. The battery-powered Small Move (20x40cm, 120 LEDs) suits a single joint and goes with you around the house. The new plug-in Mighty Medium (80x30cm, 360 LEDs) covers three times the area, enough for your whole lower back and hips in one session. Which one you need depends on how much of your body is complaining.

Think about where it hurts right now. Some people can point to the spot with one finger: the left knee, the right shoulder. Others wave a hand across the whole lower back and say, somewhere around here. Ask yourself now: which are you? That one answer does most of the work in choosing a belt.

Why a belt sits closer than a panel

A big panel on a stand looks brilliant in the living room, next to the varmepumpe and the good lamp. Everything looks modern and tidy. Wonderful, but you have to stand in front of it, at a distance, and on a dark evening that is exactly the part that doesn't happen. Most people who buy a panel use it hard for three weeks and then it quietly becomes a coat stand. This isn't me being all high and mighty about it, it's just what busy lives do to good intentions. (I sell panels too, and they are the right tool when you want wide coverage. A sore knee at 9pm is a different job.)

Light spreads out and weakens as it travels, so 30cm back from a panel is a different dose from a pad lying flush on your skin. I've written about how distance and irradiance change what actually reaches you. When the light does arrive, red light therapy (photobiomodulation) works at the level of your mitochondria, the power stations inside your cells, where an enzyme called cytochrome c oxidase appears to be the main target. Michael Hamblin's 2017 review of the anti-inflammatory effects of photobiomodulation describes what follows: more ATP, a short burst of reactive oxygen species, more nitric oxide, and lower inflammatory markers in cells that were already stressed.

Small Move or Mighty Medium: which belt for which problem?

The Small Move is the one you forget you're wearing. It is 20x40cm, weighs 0.58kg and runs on a built-in battery for up to two hours depending on intensity, so it goes onto a knee, shoulder, elbow or ankle while you cook, answer email or walk around the house. It travels well too, and anyone who has sat in a cold hytte in February with a stiff knee will see the appeal. USB charging takes three to four hours.

The Mighty Medium is the new one, and it is a different animal. At 80x30cm with 360 LEDs it covers three times the area, so your whole lower back and hips, both knees at once, or the full length of your thighs after a hard session all fit under one belt. The trade-off is a power socket: it runs from a 45W mains adapter, so it is a sofa-or-bed belt rather than a walk-around belt. Both have continuous and pulsed modes, and the Mighty Medium adds dimming, which helps on areas that feel sensitive. Both use the same triple-chip LEDs, with one 660nm red chip and two 850nm near-infrared chips in every LED, so the light itself is identical. What changes is how much of you it covers and whether you are tied to the wall.

For ryggsmerter I would reach for the Mighty Medium. For leddsmerter in one place, like a knee or a shoulder, the Small Move is usually enough, and for muskelgjenoppretting after training it depends on how big the muscle group is. I've written up red light therapy for knee pain and red light therapy for back pain if you want the detail. And if you're weighing a belt against a panel, this post on battery-powered wraps versus panels is worth a read.

What the research says, and where it stops

I'll start with my own experience, because it's the weakest kind of evidence and I'd rather say so up front. There are mornings when my ankle arthritis has me negotiating with my ankle all the way to the kettle. After a few days in a row of morning red light sessions, the stiffness is less. Not gone. But less. That matters to me, and it's why I care more about a belt you'll actually use than one with the best-looking spec sheet.

Now the better evidence, with its limits. A 2019 study published in BMJ Open pooled 22 randomised placebo-controlled trials with 1,063 participants and found that low-level laser therapy reduced knee osteoarthritis pain by about 14mm on a 100mm scale compared with placebo at the end of treatment. You can read the full paper here. Those were lasers at 785 to 860nm delivering set doses to each spot, not LED belts, so treat it as supporting evidence for the wavelengths and not as a trial of this product.

A 2024 systematic review in Physical Therapy (abstract here) found that photobiomodulation reduced pain at rest in knee osteoarthritis compared with placebo. The authors rated the certainty of that evidence as very low, and suggested using it alongside other recommended treatments rather than on its own. An earlier 2015 meta-analysis in Osteoarthritis and Cartilage (here) found no significant difference from placebo, which is a good reminder that dose and parameters decide a lot. The cell biology is well established. How well it translates into your particular knee is still being worked out, and I'd rather tell you that than pretend the case is closed.

How much is enough: the dose question

Almost nobody selling red light devices in Norway talks about this, and I think that's a problem: more light is not better light. Huang, Hamblin and colleagues' review of the biphasic dose response describes how lower doses stimulate cells while higher doses can inhibit them. A belt sitting flush on your skin delivers a concentrated dose, which is why the guidance is 10 to 20 minutes, once or twice a day, and not an hour because you're feeling brave. If an area feels sensitive, the Mighty Medium's dimming lets you turn it down instead of cutting the session short.

Claims matter here too. I test every device with a spectrometer before I'll stock it, and I've sent things back when the readings didn't match the claimed specs. Not fun conversations, but necessary ones.

Buying a red light therapy belt in Norway

Both belts ship from my stock in Drammen, so there are no customs fees or surprise import bills, and the Mighty Medium qualifies for free shipping on its own. You get 30 days open purchase with a full refund, plus a personal usage guide from me by email, matched to what you're treating and which belt you chose. You can see both on the red light therapy belt product page, or browse the full portable red light therapy range. If you're still unsure, message me with what hurts and I'll tell you which one I'd pick. That's what I'm here for.

For general wellness. Not intended to diagnose, treat, cure or prevent any disease. Consult your healthcare provider if pregnant or managing a medical condition.

Frequently asked questions

Should I buy the Small Move or the Mighty Medium red light therapy belt?

It depends on how much of your body you want to treat at once. The Small Move (20x40cm, 120 LEDs, built-in battery) suits a single joint like a knee, shoulder, elbow or ankle, and you can wear it while you move around. The Mighty Medium (80x30cm, 360 LEDs, plugs into the wall) covers three times the area, so it suits the whole lower back, hips or both thighs. Both use the same triple-chip LEDs with 660nm red and 850nm near-infrared light.

Does a red light therapy belt work better than a red light panel?

Neither is better across the board, because they do different jobs. A belt sits flush on your skin, so there is no air gap between the light and the area you want to treat, and you can sit or lie down while it runs. A panel covers a larger area from a distance, which suits wider sessions. Many people use a belt for the problem area and a panel for broader coverage.

How long should I use a red light therapy belt each day?

The guidance for both belts is 10 to 20 minutes per session, once or twice a day. More is not better, because research on the biphasic dose response suggests that too much light can reduce the effect instead of increasing it. If an area feels sensitive, the Mighty Medium has dimming so you can lower the intensity. Start at the shorter end and build up if it suits you.

Can I use the Mighty Medium red light therapy belt without a power socket?

No, the Mighty Medium runs from a mains power adapter and has no battery. That is the trade-off for three times the LEDs and treatment area, and it also means there is no battery to run flat in the middle of a session. If you want to move around the house or use a belt at a cabin without a socket nearby, the Small Move has a built-in battery that lasts up to two hours depending on intensity and charges by USB in three to four hours.

Hva er et rødlysterapi-belte, og hvilket bør jeg velge?

Et rødlysterapi-belte er en fleksibel LED-pute som festes direkte mot huden og gir rødt lys på 660nm og nær-infrarødt lys på 850nm mot ett område, som kne, skulder eller korsrygg. Small Move (20x40cm, 120 LED-er) har innebygd batteri og passer til ett ledd du vil behandle mens du beveger deg. Mighty Medium (80x30cm, 360 LED-er) kobles til strøm og dekker tre ganger så stort område, for eksempel hele korsryggen og hoftene i én økt. Mange bruker dem ved leddsmerter, ryggsmerter og for muskelgjenoppretting etter trening.

Hvor kjøper jeg rødlysterapi-belte i Norge, og hva med frakt og retur?

Begge beltene sendes fra lageret mitt i Drammen, så du slipper tollavgifter og uventede importregninger. Mighty Medium koster over 3 000 kr og får derfor gratis frakt. Du får 30 dagers åpent kjøp, og med hver bestilling får du en personlig bruksveiledning fra meg på e-post. Er du usikker på hvilket belte som passer, kan du sende meg en melding om hva som plager deg.

References

Hamblin MR. Mechanisms and applications of the anti-inflammatory effects of photobiomodulation. 2017.

Efficacy of low-level laser therapy on pain and disability in knee osteoarthritis: systematic review and meta-analysis of randomised placebo-controlled trials. BMJ Open, 2019.

Effectiveness of photobiomodulation in reducing pain and disability in patients with knee osteoarthritis: a systematic review with meta-analysis. Physical Therapy, 2024.

Effectiveness of low-level laser therapy in patients with knee osteoarthritis: a systematic review and meta-analysis. Osteoarthritis and Cartilage, 2015.

Huang YY, Chen AC, Carroll JD, Hamblin MR. Biphasic dose response in low level light therapy. Dose-Response, 2009.

About the author

Dominic Lamb runs Home Light Therapy from Drammen, Norway's oldest independent red light therapy store (since 2018). He started it because of his own arthritis and the energy drain of Northern European winters, and he tests every device with a spectrometer before stocking it. More about Dominic and the mission.