Running on a sunny day is both a thrill and a challenge.
On one hand, there’s nothing quite like the feeling of hitting the pavement or trails on a bright, sunny day. While it feels great, the sun can also mean extra precautions to avoid dehydration or sunburn.
As someone who lives in a tropical country who also has coached many runners through every kind of weather, I’ve learned that being prepared is important.
So, let’s dive into what you need to know to make the most of those sunny runs while staying safe.
The Dangers Of Sunburns
Sunburns aren’t just about a little redness and discomfort—they can lead to serious health risks. Prolonged exposure to the sun increases your chances of dehydration, heatstroke, and, more importantly, skin cancer.
Let’s look at some numbers to see just how serious this can b:
- Skin cancer is the most common cancer in the U.S., more frequent than cancers of the lung, breast, prostate, and colon combined.
- Around 5 million people are treated for skin cancer annually in the U.S.
- One in five Americans will develop skin cancer in their lifetime.
- According to the American Cancer Society, one person dies from melanoma every hour.
As runners, we often spend extended periods outdoors, especially when training for long races like marathons or ultras. This increases our exposure to harmful ultraviolet (UV) radiation, which is the leading cause of skin cancer.
And please don’t take my word for it.
Research shows that runners have a higher number of age spots and abnormal moles, both of which are warning signs for skin cancer.
Marathoners, in particular, are at greater risk because of the amount of time they spend in the sun and how intense their training can be.
But it’s not just the exposure. Long, intense workouts can weaken your immune system, making your skin even more vulnerable to UV damage. This is why it’s so important to take sun safety seriously.
Runners and Skin Cancer
like many runners, I didn’t always think about the sunscreen thing. But learning that marathon runners are more prone to skin damage made me think twice. If you’re out there for hours in the sun, UV rays can really take a toll. It’s worth paying attention
And let’s face it, we runners don’t always think about sunscreen as much as we should. I mean who has the time for that.
This isn’t just me talking: my statement is based on many scientific papers.
One example is an Australian study in which researchers reported that marathon runners suffer more abnormal moles and other skin lesions often associated with skin cancer than a less-outdoorsy control group.
Another research published in the Archives of Dermatology reported that marathoners had increased numbers of age spots and abnormal moles—all of which increase the risk for malignant melanoma.
The reason is obvious.
When you spend extended periods training under the ruthless sun, you expose your skin to high levels of ultraviolet (UV) radiation, the most detrimental environmental risk factor for skin cancer.
Not only does spending extended periods outdoors increases exposure, but research also found that long intense training—think long-distance training—may suppress the immune system, which makes you more prone to skin damage.
Is It Okay To Run In The Sun?
Running in the heat can be safe if you know what to watch out for and take a few extra precautions. It’s all about preparation and understanding the conditions.
Nowadays, I never leave the house without sunscreen, a hat, and a good pair of sunglasses to protect my eyes. I also try to plan my runs early in the morning or later in the evening to avoid the sun’s peak hours. More on this later.
Why Is Running In The Sun Harder?
Ever feel like running under the sun is way harder than it should be? That’s because your body has to work overtime to keep cool—making sunny runs feel like an extra workout
Let me explain more.
When the sun is out, your body has to work extra hard to regulate its temperature. This means your heart rate increases, and your cardiovascular system has to pump more blood to your skin to cool you down, leaving less oxygen and energy for your muscles.
Running in high temperatures can drain your energy faster, increase your perceived exertion, and make it harder to maintain your regular pace.
It’s not just about feeling hot—it’s about your body working much harder to keep cool. This is why a sunny day can feel significantly more challenging than a cooler, overcast run, even if you cover the same distance at the same pace.
The Pros of Running in the Sun
Believe it or not, there are benefits to running in the sun, too.
Let’s dive in a little deeper:
Simulates Altitude Training
Believe it or not, running in the heat can actually improve your endurance! After a few hot runs, I noticed my body adapting—sweating less and cooling down faster. That’s because running in heat pushes your cardiovascular system to be more efficient.
Don’t take my word for it.
Studies show that training in the heat can improve your blood plasma volume, reduce overall body temperature, and even increase the force of your skeletal muscles. It makes your cardiovascular system more efficient, helping you run faster and farther, especially in extreme conditions.
Sun Exposure
Sun exposure helps your body produce vitamin D, which is crucial for bone health, immune function, and overall well-being. Lack of vitamin D has been linked to issues like depression, weight gain, and even certain cancers. However, you don’t need hours in the sun to get your fill—just 10 to 15 minutes of sun exposure can help your body produce the necessary vitamin D.
Make You Faster
Here’s a cool fact: studies have shown that exposure to UV rays can improve performance.
One study found that cyclists who spent 20 minutes under UVA rays performed better, likely due to the release of nitric oxide. This compound increases blood flow, delivering more oxygen and nutrients to your muscles.
So, while you still need to be cautious about too much sun, a little exposure might help you run faster.
How To Avoid Sunburns When Running In The Sun
Here are a few safety measures to help you protect your skin throughout your summer workouts.
Choose the Right Sunscreen
Recent surveys have revealed that just over 14 percent of American men and only 30 percent of American women slather on sunscreen before going out.
This simple measure might be the easiest way to prevent millions of yearly cancer cases.
But…
Not all sunscreens are created equal.
Look for a broad-spectrum sunscreen—this protects against both UVA and UVB rays. Shoot for an SPF of at least 30, or higher if you’re fair-skinned or plan to run for an extended period.
My best advice? Go for water-resistant options so it holds up as you sweat. Some runners love sports-specific sunscreens designed to stay put during intense activity.
I’d also recommend tying a mineral-based sunscreen (like zinc oxide or titanium dioxide) if you have sensitive skin—these physical blockers sit on top of your skin and can be gentler than chemical formulas.
Put On Your Sunscreen the Right Way
A common mistake is applying it too quickly before heading out.
Here’s what you should be doing: Apply sunscreen at least 20 to 30 minutes before you head out, giving it time to bond with your skin.
Cover all exposed areas: your face, neck, ears, arms, and legs. Don’t forget the tops of your feet if you’re running in sandals or open shoes! And if you’re going on a long run, reapply after 60 to 90 minutes. This can be tricky during a race, but it’s a must for training runs.
Remember to reapply every two hours for extended runs, or sooner if you’re sweating heavily.
Wear UPF-Rated Clothing
Investing in UPF-rated running gear can provide extra protection against UV rays. UPF (Ultraviolet Protection Factor) measures how well fabric blocks UV radiation. A shirt or hat with UPF 50, for example, blocks 98% of UV rays, helping prevent burns on areas not covered by sunscreen.
- UPF Shirts and Jackets: Lightweight, long-sleeve shirts with UPF ratings keep your arms and shoulders protected without making you overheat.
- UPF Hats: Look for hats with wide brims or neck flaps for extra coverage on your face and neck.
Coach’s Tip: Brands like Columbia, Patagonia, and Under Armour offer UPF-rated clothing designed specifically for active use, so you can stay protected without sacrificing breathability.
Protect Your Eyes with Polarized Sunglasses
Running in bright sunlight can strain your eyes, so wearing polarized sunglasses is a smart move. Polarized lenses reduce glare from surfaces like roads and water, providing clearer vision and reducing eye strain. Look for wrap-around designs to block UV rays from multiple angles.
Run Early Or Late
To minimize sun exposure, plan your runs during the early morning or late evening when the sun is less intense. Try to get out before 10 a.m. or after 4 p.m. to dodge the strongest UV rays.
Running early isn’t just cooler—it’s a quieter, more peaceful time of day, plus you avoid the worst of the UV rays..
Consult A Dermatologist
These days, I see a dermatologist regularly. I figure that with all the time I spend outside, it’s worth getting checked out once a year to make sure everything’s okay. Knowing that potential issues can be caught early is a small step for peace of mind.
Sun Safety Checklist for Runners
Before you head out for a sunny run, make sure you’re prepared with these essentials. Here’s a quick checklist to keep you safe and comfortable:
- Apply Sunscreen
- Broad-spectrum SPF 30+ sunscreen
- Reapply every 2 hours (or sooner if sweating heavily)
- Consider mineral-based options for sensitive skin
- Wear UPF-Rated Clothing
- Lightweight, long-sleeve shirt or jacket with UPF protection
- Wide-brimmed hat or cap with neck coverage for extra face protection
- Protect Your Eyes
- Polarized sunglasses with 100% UV protection
- Wrap-around style for better coverage
- Stay Hydrated
- Drink water before, during, and after your run
- Consider carrying a water bottle or hydration pack for longer runs
- Electrolyte drinks for extra hot days to replace lost minerals
- Adjust Your Timing
- Try to run during early morning or late afternoon to avoid peak sun hours (10 am – 4 pm)
- Use shaded routes if possible to reduce direct sun exposure
Feel free to print or save this checklist to keep your sun-safety routine simple and consistent. Every step counts toward a safer, more enjoyable run in the sun!
Join the Conversation: Share Your Sunny Run Tips!
Running in the sun can be a rewarding experience, but every runner has their own strategies for staying safe and comfortable.
What’s your go-to strategy for sunny runs?
Jump into the comments below to share your experiences, go-to gear, and any advice you’ve found helpful.
Your insights can help fellow runners enjoy their sunny runs safely and comfortably!