Both work. They just do slightly different things. Pre-workout light boosts endurance while post-workout reduces muscle damage.

Before a workout, light primes the muscles for performance. After, it supports recovery. The few studies that have directly compared the two windows found that both reduce muscle damage equally, but pre-exercise has a performance edge that post-exercise doesn't. The real answer depends on what you're optimizing for.

You can use light both ways. A quick pass with the Ironforge before training, and another after if the schedule allows. The session is short enough to fit into a warm-up.

If you only have time for one, match it to your goal. Training hard today? Before. Recovering from yesterday? After.

If you're looking into red light therapy for sleep, here's what research says, what it doesn't, and what you can do about it this evening.

Key Takeaways:

• Red light doesn't suppress melatonin making it a smart choice for evening lighting. But evidence that red light therapy actively IMPROVES sleep is weaker than commonly claimed.
• Daytime light exposure is the most underrated factor in sleep quality. Bright stimulating light during the day increases nighttime melatonin levels and makes your circadian system more resilient to evening light disruption.
• Sleep is driven by CONTRAST. The difference between your daytime and nighttime light environment matters more than any single device or hack.
• An evidence-based approach means optimizing the full light cycle. Bright days, dim amber/red evenings, and dark nights.

Your eyes and skin contain specialized light sensors called melanopsin. These cells don't help you see, they tell your brain what time it is.

Melanopsin is maximally sensitive to cyan (sky blue) light around 480nm. When stimulated, it signals the brain's master clock to suppress melatonin production and prepare you for sleep.

During the day, this is exactly what we want. This keeps us alert, focused, and feeling alive.

The problem is that our phones, laptops, and overhead lights, all emit significant amounts of stimulating melanopic light. When you're scrolling at 11pm, your brain is getting a daytime signal. Melatonin stays suppressed, sleep onset gets delayed, and sleep quality drops.

Red light in the evening doesn't suppress melatonin. This is well-documented, and quite useful.

But notice the claim here is “red light doesn't interfere with sleep.” That's vastly different from saying it actively improves it.

Darkness also doesn't suppress melatonin, yet very few people are writing blog posts about how darkness is an effective sleep therapy.

There is no single correct session length. Across more than nine thousand published photobiomodulation studies, positive outcomes have been documented with session times ranging from under one second to over an hour. What seems to matter is total energy delivered to the tissue, which is a function of both irradiance and time, this also has a very wide range of positive outcomes. A high-irradiance device like the Chroma Ironforge (850 mW/cm² at the faceplate) delivers a meaningful dose in 30seconds to three minutes per area. A lower-power device may need fifteen to forty minutes for a comparable dose. Start with shorter sessions, increase gradually, and stay consistent.

Photochemical overdose in the body from red and near-infrared light has not been demonstrated at irradiance levels used by consumer devices. A six-hour walk in the sun and shade delivers 170 to 320 J/cm² of red and NIR light to your skin, far exceeding typical device protocols, and nobody has ever been harmed by a day outdoors from these wavelengths. The practical limit is thermal: if the device feels uncomfortably warm against your skin, move it to a different area, or increase your distance. Allow tissue to cool before continuing. More exposure is not always better, but the effective range is wide enough that precise dosing is unnecessary.

Consistency matters more than any single session parameter. Studies showing meaningful results typically involve regular use over weeks or months. Daily or near-daily sessions of a few minutes generally produce better outcomes than occasional long sessions. The goal is to reintroduce light exposure that modern indoor living has eliminated, not to achieve a precise one-time dose. Think of it as a daily habit like drinking water, rather than an occasional treatment like a massage.