As the days grow shorter and the chill sets in, it’s easy to let your connection to sunlight slip into hibernation. But according to David Herrera, also known as The Solar Athlete on Instagram, winter is not the time to hide from the sun – it’s the time to get smarter about how you use it.

A performance coach and former powerlifter who rebuilt his life and health through a deeper relationship with light, David now teaches people how to thrive year-round by aligning with the natural environment. His advice is simple but profound: don’t retreat from winter – engage with it.

Here’s how he does it.

1. Stay Outside, Stay Exposed

"I don’t change anything," David says of his winter routine.
"I keep going outside exactly like it's summertime."

That means no heavy layering, no artificial light dependency, and no hiding from the cold. He continues to work outdoors in swim shorts as much as possible – even in freezing temperatures. For most people, this might seem extreme. But David emphasizes that it’s not about suffering. It’s about harnessing natural cold as a biological input, much like sunlight.

If you're not up for the full immersion, David recommends dressing down gradually in fall, especially in October and November, to build tolerance while the temperatures are still manageable.

2. Use Cold as a Supplement to Weak Sunlight

Winter sunlight is limited in duration and intensity – especially in northern latitudes. But your body has a secret weapon: it can generate its own light.

When your skin senses cold (below 55°F or ~13°C), your mitochondria increase their output of ultra-weak photon emissions (UPEs) – a form of internal light that helps maintain circadian rhythm and support cellular health.

"If each mitochondrion is like a little sun," David explains, "then your cells are like solar systems."

You don’t need extreme cold or a full ice plunge. Just stepping outside in minimal clothing for 20–30 minutes can be enough to activate this internal light-generating response.

3. Sunlight Still Matters in Winter – Even When It’s Cold

David lives at high altitude in Wyoming, where UV light is still present year-round. On sunny days, he sunbathes even at sub-zero temperatures.

"If there’s UV – even in the snow – I’ll go out and tan," he says.

In cold weather, melanin shifts roles: instead of primarily protecting you from UV (as in summer), it begins to amplify UV absorption to help your body make the most of every ray of light. This helps explain why indigenous peoples in both hot and cold climates have darker skin – melanin supports both heat regulation and sunlight capture.

4. Artificial Light Hygiene is Even More Critical in Winter

With daylight hours shrinking, the circadian system becomes more vulnerable to artificial disruption. David recommends:

• Avoiding blue-rich LED lighting after sunset

• Switching to incandescent bulbs for nighttime use

• Using candlelight or firelight where possible

• Turning off Wi-Fi overnight (use a timer switch for simplicity)

"The body prepares for blue light in the middle of the day," David explains.
"When you hit it with blue light at night, it scrambles the clock."

In winter, this mismatch can lead to chronic fatigue, poor sleep, brain fog, and mood issues. The solution? Respect the natural light/dark cycle as much as you can.

5. Winter is About Rhythm, Not Rigidity

You don’t need to become a solar monk to benefit from this wisdom. David’s approach is flexible and practical. If you can’t spend all day outside, aim for short, regular exposures at key times – especially early morning and midday.

"It's a clock," he says.
"You have to wind it regularly."

Even 5–10 minutes of sunlight exposure upon waking can help set your biological clock for the day. Later, a short break outside – especially when experiencing brain fog – can reset your focus and restore your energy.

Final Takeaway: Don’t Hibernate – Adapt

Winter doesn’t have to mean a drop in energy, mood, or health. With simple adjustments, you can turn cold and low sun into allies rather than enemies.

David’s protocol is a reminder that nature provides the tools – we just have to learn how to use them.

Simple Winter Hacks Inspired by David Herrera

• ❄️ Expose your skin to cold air in the morning

• ☀️ Seek natural light daily, even in overcast weather

• 🔥 Use incandescent bulbs after sunset

• 🕯 Switch to candlelight or warm lamps at night

• 🌐 Turn off Wi-Fi while sleeping

• 🧊 Use cold water (on face or throat) for nervous system reset

Want to Explore Sunlight Like Never Before?

Use Shadowmap to track sun paths, solar exposure, and shadow impact in real-time – perfect for home planning, urban design, or optimizing your own circadian-friendly lifestyle.