Runners Face: What a Dermatologist Does Before and After a Run

I'm Dr. Hongseok Kim, a board-certified Korean dermatologist with 21 years of practice and the medical director of VOS Dermatology Clinic in Gangnam, Seoul, in front of Dosan Park. At VOS I see every patient myself, from the consultation to the treatment.

More of my patients run now, and some ask whether "runners face", the drawn, older look people talk about online, is something they should worry about. Running is good for your health, but a hard run does put stress on the skin, and most of that stress can be managed with what you do before and after. This page is based on my YouTube video from October 2025, filmed outdoors with a guest who took up running; I rewrote it for readers abroad. The video above can be watched with translated captions.

One honest limit first: runners face is not a medical diagnosis, and the video does not discuss facial fat loss or volume. It covers what running does to the skin itself and the routine I recommend around a run.

Is running bad for your skin?

Short answer: running is good for your body, but how you look after your skin before and after it matters more than the running itself (in the video at 01:44).

Running needs a lot of oxygen. When more oxygen comes in than the mitochondria can fully handle, part of it is left over as free radicals (reactive oxygen species). For overall health and fitness, running has many benefits; for the skin directly, those free radicals can add to damage and aging if you do nothing about them (in the video at 02:03). That is my personal view: the exercise is not the problem, poor care around it is.

What to put on before a run

Short answer: keep textures light, toner, serum and a light cream are fine, and add sunscreen as a basic set (in the video at 03:56).

During a run your body temperature rises, pores open, circulation speeds up and you sweat. A thick cream or oil applied first can feel heavy and uncomfortable as that happens. My guest uses a serum before running and a cica cream before and after, which is a sensible pattern; serums with soothing ingredients such as panthenol are worth using for the reasons below.

Sunscreen is the step not to skip in daylight (in the video at 04:09). For running I prefer a mineral (physical) sunscreen or a water-resistant formula. Chemical sunscreen comes off with sweat, and every time you wipe your face with a towel you remove more of it (in the video at 11:05). By the end of the run you are sweaty, your skin is hot, and you are in full sun with almost no protection left. If you want the general rules on choosing and reapplying, my video note on how I choose a Korean sunscreen for face covers them.

What sweat does to your skin during a run

Short answer: sweat leaves the skin both dehydrated and more alkaline, which weakens the skin barrier (in the video at 05:18).

At the end of a run you are soaked in sweat, your skin temperature is up and your face is red. To shed heat, the sympathetic nervous system dilates the small blood vessels in the skin, and water escapes along with the heat (in the video at 04:50). So the first step is simple: drink water.

Sweat starts out at roughly the same salt concentration as the body, about 0.9% sodium chloride. As the water in it evaporates on your skin, what remains becomes more concentrated, and that draws water out of the skin cells (in the video at 05:39). The cells shrink, and you feel tightness, dryness and, when it is strong, stinging or itching. Your skin may look wet, but the cells underneath are drying out.

Sweat also changes pH. Healthy skin sits at about pH 4.5 to 5.5, while sweat ranges from about 4.5 up to around 7.0 (in the video at 06:14). As sweat keeps drying on the skin, the salts and ammonium-type compounds it leaves shift the surface toward alkaline, and the barrier weakens.

How to cleanse after running

Short answer: wash with a weakly acidic (low-pH) cleanser, not plain water and not a harsh cleanser (in the video at 07:06).

Tap water is around pH 7.0 to 8.0 (in the video at 07:18). On skin that sweat has already pushed toward alkaline, rinsing with water alone moves it further in the same direction. After a water-only wash, it normally takes one to two hours for skin pH to come back (in the video at 07:49). Healthy skin copes; skin that is already red-prone or sensitive gets weaker during that window. A weakly acidic cleanser brings the pH down faster, and then the toner, serum and cream that follow can focus on barrier repair. A cleanser that is too strong works against you here.

Redness and heat after a run: cool, not ice-cold

Short answer: bring the temperature down, but use cool water or a damp towel, not ice (in the video at 09:29).

When you stop running, muscle work and body heat drop quickly and the parasympathetic system switches on abruptly. The vessels in your facial skin, however, can stay dilated, so the heat and redness linger (in the video at 08:52). If your face already flushes easily, that reaction is stronger, and with repetition the vessels have less time to settle back, which can make redness more persistent. That is why cooling matters.

The most common mistake is very cold water or ice. Skin surface temperature is about 32°C, so water at 10 to 20°C feels extremely cold to the skin (in the video at 09:37). The vessels clamp down for a moment, then rebound, and the face can turn redder afterwards. Water in the low-to-mid 20s °C, cool but not cold, works better; simply soak a towel and press it to your face (in the video at 10:27). If redness stays even when you are not exercising, it is worth having it assessed; my guide to Korean rosacea treatment explains how we look at persistent redness.

Three steps after a run: hydrate, seal, protect from inside

Short answer: put water back into the skin with a serum, seal it with a cream or squalane oil, and support the body with fluids and antioxidants (in the video at 12:47).

Many people think heavy sweating leaves skin more moist. In fact, for the reasons above, the skin cells lose water, so I use a serum to draw water back in. Sweat, sebum and cleansing have also stripped the protective film from the surface, so a cream or squalane oil is needed to rebuild it (in the video at 13:23). An antioxidant serum such as vitamin C is useful, retinal is a good option too, and a sheet mask is fine.

After a run people often look older and saggy for a while, partly because they have lost one to two litres of fluid (in the video at 13:55). Replace at least that much. Plain water has a lower salt concentration than body fluid, so after heavy sweating don't drink only water; a low-sugar electrolyte drink, including the powdered kind, helps (in the video at 14:41).

Finally, take antioxidants: vitamin C, vitamin E, glutathione and coenzyme Q10 are all options (in the video at 15:26). Hard aerobic exercise produces oxidative damage in both water-based and fat-based parts of the body, and antioxidants help offset the downside of running so you keep its benefits. If you would rather ask about antioxidant support in person, our IV clinic in Seoul prescribes formulations individually after a diagnosis. For a wider view of how I layer care against aging, see my guide to Korean anti aging, and our creator experiences at VOS show how visitors fit clinic care into an active trip.

Results vary from person to person, and the right plan for your skin is decided at an in-person consultation.

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Results, swelling and recovery vary from person to person. This page is general information from VOS Dermatology Clinic based on Dr. Kim's video and does not replace an in-person consultation.