If you practise outdoor sport, you've probably already experienced at least one of these situations: sunscreen running into your eyes during a run, that greasy feeling on your skin that interferes with your grip, or you've simply stopped applying it because it's “annoying”. This is a widespread problem. And it's also one of the most underestimated risks in outdoor sport.
This guide answers a precise question: what really makes a sunscreen suitable for sport? And how do you choose the right one based on the activity you practise? SUNO developed its formulations starting from these questions, working on real conditions of use — not laboratory ones.
WHAT MAKES A SUNSCREEN SUITABLE FOR SPORT
Not all sunscreens are the same. Those designed for the beach are formulated for passive exposure conditions: you stay still, you sweat little, you dry off with a towel and reapply comfortably. In sport, conditions change radically.
A sunscreen for sport must meet precise technical requirements that traditional sunscreens often fail to meet.
Sweat resistance
During intense physical activity, an inadequate formula dissolves, runs and loses effectiveness within minutes. A sunscreen for sport must maintain its hold even under the most extreme sweating conditions.
Breathability
Skin needs to breathe to regulate body temperature. An occlusive formula interferes with this physiological process, compromising performance. Advanced sports formulations are designed not to block pores and to allow normal thermal regulation.
Lightweight texture and fast absorption
A good sunscreen for sport absorbs within seconds, without visible residue and without white cast. No greasy residue that interferes with grip or the use of equipment.
Doesn't run
This is the most immediate requirement and the one most overlooked by traditional sunscreen manufacturers. If the cream runs into your eyes during a bike descent or a climbing session, you stop using it — and at that moment you're no longer protected.
Broad spectrum
A sunscreen for sport must protect against both UVB rays (responsible for sunburn) and UVA rays (responsible for photo-ageing and implicated in the development of melanoma). Broad spectrum certification is non-negotiable.
SPF 50+ broad spectrum: why it's the standard for athletes
The SPF number indicates the level of protection from UVB rays under laboratory conditions. The real conditions of an athlete are very different.
During physical activity, several factors reduce the practical effectiveness of sun protection:
- Sweating dilutes and removes the product from the skin.
- Friction from clothing, gloves or equipment straps mechanically removes the protective film.
- Altitude increases the intensity of UV radiation by around 4-5% every 300 metres.
- Reflection off snow, water or sand multiplies actual exposure: snow can reflect up to 80% of UV radiation.
For these reasons, the leading international dermatological organisations recommend a minimum SPF of 30 for outdoor activity, with a preference for SPF 50+ in the prolonged exposure conditions typical of sport. The Skin Cancer Foundation indicates SPF 50+ as the standard for intense and prolonged exposure during sporting activity.
Broad spectrum certification guarantees that the product also protects against UVA rays, which — unlike UVB — do not cause immediate sunburn but penetrate deep into the dermis, accelerating photo-ageing and increasing the risk of melanoma in the long term.
Sunscreen for trail running, cycling, mountaineering and water sports: which to choose
There is no single sunscreen suitable for all sports. The environmental conditions and physical characteristics of different disciplines require specific formulations.
Sunscreen for trail running, running, cycling, climbing
For high-sweat disciplines with prolonged movement, the priority is sweat resistance combined with breathability. The formula must remain effective without running into the eyes and without greasy residue that interferes with grip or the use of equipment.
Application should be done at least 20-30 minutes before the activity, to allow the product to adhere fully to the skin's surface before sweating begins.
The reference formulation is SUNO AIR: an SPF 50+ face and body cream developed for high-intensity sport.
For those looking for a formulation dedicated exclusively to the face with an additional anti-ageing action, the choice is SUNO FACE.
Sunscreen for mountaineering, ski mountaineering and high-altitude sport
At altitude, UV risk increases significantly: radiation grows by around 4-5% for every 300 metres of elevation gain. Added to this is reflection off snow, which can return up to 80% of UV radiation, exposing skin even in areas normally in shade.
Conditions at altitude — cold, wind, variable humidity — require a formula enriched with ceramides and soothing ingredients, capable of reinforcing the skin barrier as well as protecting against UV rays.
For high-altitude sport, the specific formulation is SUNO ALPINE: an SPF 50+ sunscreen for face and body developed for the environmental conditions of high mountains.
Sunscreen for water sports: swimming, surfing, kitesurfing, sailing
For water sports, the main requirement is resistance to prolonged immersion. Traditional formulas, even those with a water-resistant claim, can fail quickly on prolonged contact with salt or chlorinated water.
For this type of sport we are developing SUNO AQUA: an anhydrous formula rich in natural oils and waxes that creates a hydrophobic barrier capable of maintaining adhesion to the skin even during prolonged immersion, with reef-safe ingredients. Launch is planned for summer 2027.
How to correctly apply sunscreen during sporting activity
Even the best formulation loses effectiveness if applied incorrectly.
Quantity
The recommended dose is 2 mg per square centimetre of skin. For the face, around two fingers' worth of product is needed. Most people apply less than half the recommended dose, reducing the effectiveness of protection by up to 50%.
Timing
Apply the cream at least 20-30 minutes before sun exposure, to allow the protective film to adhere fully to the skin before sweating begins.
Reapplication
Reapply every two hours, and always after sessions of intense sweating. No sunscreen, not even SPF 50+, maintains its effectiveness indefinitely. Reapplication is the most underestimated factor in sports sun protection.
Critical areas
Don't neglect ears, the back of the neck, and the backs of hands and feet. For athletes at altitude, it is essential to also protect areas of the face normally in shade, which in the mountains receive radiation reflected from snow.
FAQ: the most frequently asked questions about sun protection for athletes
Should I use sunscreen in winter or on cloudy days too?
Yes. UVA rays are present all year round and penetrate through clouds. In the mountains in winter, the combination of high altitude and reflection off snow makes UV exposure particularly intense.
Does sunscreen interfere with performance?
A traditional sunscreen can — by clogging pores and increasing the sensation of heat. A quality sports formulation is specifically designed not to interfere with skin thermoregulation.
Should I apply sunscreen even if I'm already tanned?
Yes. A tan offers protection equivalent to an SPF of around 2-3 — entirely insufficient for any outdoor sporting activity. UV exposure accumulates long-term damage regardless of skin colour.
SPF 30 or SPF 50+ for sport?
For outdoor sporting activity, SPF 50+ is the recommended standard. The real conditions of an athlete — sweat, continuous movement, prolonged exposure — reduce the practical effectiveness of any product compared with laboratory test conditions.
Does sunscreen cause acne?
Traditional occlusive formulas can encourage the appearance of blemishes on predisposed skin. Sports formulations with a lightweight, non-occlusive texture, such as SUNO's, are dermatologically tested on sensitive skin and generally well tolerated even by combination skin.
How long does an opened sunscreen last?
Once opened, a sunscreen generally has a shelf life of 6 or 12 months, indicated by the PAO (Period After Opening) symbol. Excessive heat can degrade its effectiveness: keep the product away from direct heat sources.
Should I use sunscreen even if I have dark skin?
Yes. People with dark skin have greater natural protection thanks to melanin, but they are not immune to damage from UV radiation — particularly long-term UVA damage. The use of SPF 50+ is recommended for any skin type during prolonged sporting activity.
Should I apply sunscreen before or after moisturiser?
Apply sun protection as the last step in your routine, after moisturiser. Let each product absorb before applying the next.
How many times should I reapply during a race or a long training session?
Every two hours as a general rule, more frequently in the event of intense sweating. For ultra-endurance races — trail, IRONMAN, high-altitude races — plan reapplications at regular intervals, just as you would with nutrition: before you run out, not after.
Discover the SUNO range — SPF 50+ sun protection formulated for every sporting discipline: SUNO AIR, SUNO ALPINE and SUNO FACE are available at sunosport.com and on Amazon.
