When we think about skin care, most of us picture lotions, sunscreen, or someone sporting a goopy green face peel and cucumber eyelids. Turns out we should add exercise to that list of mental pictures. In 2014 researchers at McMasters University in Ontario found that exercise produced remarkable changes in the skin of people over age 40. (If you’re not over 40 yet, you will be before you know it, so pay attention anyway.)

McMaster University had already studied old mice and found that mice who exercised “maintained healthy brains, hearts, muscles, reproductive organs, and fur far longer than their sedentary labmates”.  Mice who were denied access to running wheels quickly grew frail, ill, gray, and demented. Admit it: not only are you picturing a few humans you know right now, but you’re trying to remember if they exercise.

When we’re young, our body can cover up for many poor health choices. Twenty year olds can eat mostly junk, never leave the couch, and still appear healthy, but as our bodies approach middle age, we start visibly reaping what our habits have sown.

The researchers at McMaster U. turned from mice to human volunteers and biopsied skin from the one area of the body that (hopefully) had never seen the sun: the buttock. The volunteers were habitually sedentary and aged 65 or older at the start of the study, and all had normal skin for their age.

As normal skin ages, the topmost layer of the epidermis (the part you can see and touch) becomes thicker which makes the skin feel dry, flakey, and dense. The dermis, the layer of skin under the epidermis, becomes thinner, which makes the skin look saggy and translucent. That was the state of the volunteer buttocks: thicker outer layer and thinner inner layer. Mm-mmm, green face peels and dry saggy butt skin. If we continue with these mental images, this is going to be a post about weight loss, not skin!

The volunteers exercised twice a week for three months and had a butt biopsy again. (Lucky researchers.) The post-exercise skin layers looked very different; similar to the skin of 20-40 year olds. Wrinkles were not affected by the exercise, but those wrinkles were now enjoying a thinner epidermis and a nice thick dermis.

Why does exercise benefit our skin? One reason is sweat, my least favorite aspect of exercise. When our bodies get warmed up, our pores dilate. As the sweat pours forth, it carries dirt and oil with it, like a warm, salty, inside out mini shower. Speaking of showers, if you won’t be bathing soon after you sweat, it’s a good idea to at least wash your face. If you don’t rinse them off, the dirt and oil can be sucked back into your pores as you cool off. Yup, this is definitely a weight loss post.

Exercise also reduces stress and body wide inflammation, two things the medical community in general agrees we’re better off without. When we’re stressed, our glands produce less oil in our skin which causes things like acne and eczema to flare up.

Next week we’ll look at the biggest benefit of exercise for the skin: blood flow.

Whoever heeds discipline shows the way to life, but whoever ignores correction leads others astray. Proverbs 10:17 (NIV)

Images courtesy of: www.cnn.com (old and young mice), www.fitandhappy.org (skin layers), http://toppixgallery.com/ (sweat), www.care2.com (facial)