Recovery Gadgets vs Real Science: Cryotherapy, Red Light Beds and Grounding Mats Audited

Are recovery gadgets worth it? For most lifters, mostly no. Cryotherapy chambers have very thin evidence, red light is promising but unsettled, and grounding mats have nothing rigorous behind them.

This article is a skeptical audit of the gear that recovery clinics and Instagram biohackers love to sell. It sits inside our complete guide to muscle soreness and recovery modalities, so if you want the whole picture on soreness first, start there. Here we rank each gadget on an evidence spectrum from “reasonable” to “pure placebo.”

How to judge a recovery gadget in 60 seconds

Marketing loves a mechanism. “Reduces inflammation.” “Boosts mitochondria.” “Flushes toxins.” A plausible story is not proof.

Four questions cut through it:

• Is there a systematic review or meta-analysis, ideally Cochrane, and what did it conclude?
• How many people were studied, and were they trained lifters or a handful of young volunteers?
• Did the trial measure something that matters (soreness, strength, your next session) or only a blood marker?
• Was it tested against a placebo or sham, or just against doing nothing?

That last one matters more than people think. Soreness and “how recovered do I feel” are subjective. If you pay for a shiny treatment and expect it to work, you may feel better regardless.

Does whole body cryotherapy work? What the Cochrane review found

Whole-body cryotherapy (WBC) means standing in a chamber of extremely cold dry air, below -100 C, for two to four minutes. Clinics market it for soreness, recovery and “inflammation.”

The Cochrane review of WBC is the cleanest summary we have. It found just four laboratory randomised trials with 64 physically active, mostly young male adults (mean age 23, all but four participants male). All four compared WBC with rest or no treatment, all had features carrying a high risk of bias, and the authors rated the evidence for every outcome as “very low” quality (Costello et al., 2015).

The numbers look a bit encouraging at first. Soreness scores were lower after WBC at one hour (SMD -0.77, 95% CI -1.42 to -0.12). But at 24, 48 and 72 hours the confidence intervals stretched past zero, meaning the data were also compatible with no difference, or even a benefit for the control group.

The authors’ conclusion is blunt. There is insufficient evidence to say whether WBC reduces soreness or improves subjective recovery compared with rest. There was no evidence in females or elite athletes. And because no trial actively tracked adverse events, the authors flagged extreme temperature as a potential hazard they could not rule out (Costello et al., 2015).

That review was published in 2015. Newer trials may exist, but I did not find a newer Cochrane update in my search, so treat the picture as unsettled rather than final.

Cryo chamber vs cold water: which has better evidence?

Here is the awkward part for the chamber. Plain cold water immersion (water under 15 C) has a bigger pile of evidence behind it.

A Cochrane review of 17 small trials (366 participants, low study quality) found lower muscle soreness after cold water immersion versus rest or no intervention at 24, 48, 72 and 96 hours, with results that were heterogeneous (Bleakley et al., 2012). A separate meta-analysis of 36 articles found cooling, especially cold water immersion, reduced soreness at 24, 48 and 96 hours, but found no evidence that cooling changed any objective recovery marker over 96 hours (Hohenauer et al., 2015).

Notice the pattern. Cold may make you feel less sore. It has not been shown to speed up objective recovery. Whether that matters depends on your goal, and for muscle growth specifically there is a separate debate we cover in cold plunges and hypertrophy.

The practical comparison:

Option	Evidence for soreness	Typical limits	Cost level
Cold water immersion	Some evidence (17 small trials)	Low-quality trials, may not suit growth goals	Low
Whole-body cryotherapy	Insufficient (4 trials, very low quality)	Tiny samples, no safety tracking	High
Cold shower	Not directly studied here	Weaker cooling than immersion	Very low

Cold water is not risk-free. Sudden immersion triggers a gasp and a spike in heart rate and blood pressure, so if you have a heart condition, high blood pressure or circulation problems, check with a doctor first, never plunge alone, and keep sessions short.

Our guide to hot versus cold showers covers the cheap end honestly, including what a bucket of cold water in a hot Indian summer can and cannot do.

Red light therapy bed for muscle recovery: promising, not settled

Red light therapy is formally called photobiomodulation (PBM). It uses red or near-infrared light to try to influence muscle tissue. Of the three headline gadgets here, this is the one where I would not call the evidence weak, just inconsistent.

Start with the optimistic side. A review of 46 studies in 1,045 participants covering PBM in healthy trained and untrained people and athletes concluded PBM can increase muscle mass gained after training and reduce inflammation and oxidative stress in muscle biopsies (Ferraresi et al., 2016). A meta-analysis of 13 acceptable-quality trials found phototherapy applied mostly before exercise increased repetitions by 5.47 and time to exhaustion by 4.12 seconds versus placebo (Leal-Junior et al., 2015).

Now the cautious side. A meta-analysis of 16 trials in 340 healthy people found PBM helped fatigue recovery, but showed no enhancement in strength and no improvement in functional capacity (Bezerra et al., 2023). Another review of 15 studies found no between-group difference in edema, range of movement or strength, and concluded low-level phototherapy may not have a substantial effect on exercise-induced muscle injury and pain, with reduced creatine kinase seen only when laser was applied before exercise (Nampo et al., 2016).

Why the disagreement? Probably because “red light” is not one thing. Trials used lasers and LEDs, wavelengths from roughly 655 to 905 nm, and wildly different power and energy per spot. Pooling them is like pooling every kind of barbell program and asking “does lifting work?”

One more head-to-head worth knowing. A small meta-analysis of four trials (66 participants) found PBM looked better than cryotherapy for strength, soreness and muscle damage markers after high-intensity exercise, but certainty was moderate to very low (Ferlito et al., 2022). That is a hint, not a verdict.

The dosing problem with consumer red light beds

The studies above mostly used clinical devices applied to a specific muscle at a measured energy dose. The most consistent results in one meta-analysis came with red or infrared wavelengths, power between 50 and 200 mW, and about 5 to 6 J per spot, applied before exercise (Leal-Junior et al., 2015).

A full-body red light bed or home panel is a different product. I could not confirm that the clinical doses in those trials translate to a consumer bed, and the review authors themselves note device and dose variation. If a seller cannot tell you wavelength, power and the dose delivered at your skin, you are guessing.

If you have skin conditions, take photosensitising medication, or have any eye concerns, check with a doctor before using one. Protect your eyes as the manufacturer advises.

Grounding mats for athletes: the myth

Grounding, or earthing, is the claim that touching the Earth’s surface electrons, barefoot or via a mat, reduces inflammation, pain and stress and speeds recovery.

I searched PubMed for rigorous evidence in athletes and found none I could verify. The most prominent review, titled to argue that integrative medicine should include earthing, was written by practitioners who promote it. It describes about 20 studies reporting physiological improvements, and its authors conclude the practice deserves clinical inclusion (Menigoz et al., 2020).

That is advocacy from the people selling the idea, not independent, large, blinded replication. It also says nothing about lifters recovering from heavy squats.

So where does this leave you? Grounding sits in the “unproven” bucket for athletes. Sleeping on an earthing sheet is not dangerous in itself, but it is cash you could have put into a better mattress, a fan, or more protein. Walking barefoot on grass is free and fine. Just do not credit it with muscle repair.

The Simplified Fitness recovery hierarchy

This is our ranking, based on the evidence above plus our other recovery guides. It is a judgement, not a law.

1. Sleep. Nothing else comes close. Start with sleep timing and systemic recovery.
2. Food. Enough total calories and protein. Dal, paneer, curd, eggs, soya chunks and chicken all count, and they cost far less than a chamber session.
3. Training load. Volume you can actually recover from, with deloads when needed.
4. Easy movement. Gentle walking and mobility on off days.
5. Cheap, modest tools. Foam rolling, massage guns and compression if you like them. Evidence is modest and mostly about feeling better.
6. Cold water, with caution if hypertrophy is the goal.
7. Red light, only as an optional experiment once everything above is handled.
8. Cryo chambers and grounding mats. Skip them.

The hierarchy is the opposite of how clinics price things. The cheapest items at the top do the most.

When a gadget might make sense

I am not saying never. If you have already nailed sleep, protein and programming, and you are curious, a cheap trial of cold water or a session with a clinically specified red light device is a low-risk experiment. Track soreness and performance in your next sessions rather than relying on feel alone.

If you are recovering from an injury, have persistent pain, swelling or numbness, or any heart or circulation condition, see a doctor or physiotherapist before using extreme cold or light devices. Do not self-treat an injury with gadgets.

The bottom line

Recovery gadgets are easy to sell because recovery is hard to measure. The better evidence points to the dull stuff: sleep, food and manageable training. Cold water has modest support for soreness, red light is an open question, and chambers and grounding mats have not earned their prices.

If you want a structure that respects recovery in the first place, try our free training plans, then use the evidence ladder above before your next purchase.