Our skin, or integument, is the largest organ of the human body. Dermatologists just love to remind us that skin is also our most visible organ and therefore our main method of socio-sexual communication. And let’s face it: that is the main reason we focus on skin at all.

As athletes, we expand our use and view of skin, as our skin in particular is faced with special demands and situations, and its function is of increased importance to us. Let’s take a look at the dynamics of the skin for an athlete.

SUN
Triathletes typically put in many long workouts under the sun, and thus the relationship between the sun and our skin takes a higher precedence.

The sun releases three wavelengths of ultraviolet radiation: UVA, UVB and UVC. Lucky for us, UVC is absorbed by the ozone layer before it ever reaches the earth’s surface (Sorry about that, Australia). UVA and UVB rays, however, do reach the earth’s surface and also our skin, where they can produce several nasty effects.

Sunburn
The fancy medical word for sunburn is erythema, and it is caused by both UVA and UVB rays, but the latter may be the more eminent culprit. Sunburn is essentially an inflammatory reaction in our skin to the immense amount of damage that the UV rays cause in our skin cells and blood vessels. [note: In addition to making you feel better, a non-steroidal anti-inflammatory may help thwart a burn’s redness since it is an inflammatory response – consult your doctor about it. It cannot, however, thwart the damage done, just the pain]

Tanning
This is the “most sought after body blow this side of a cigarette” according to many dermatologists. Our fancy medical word here is hyperpigmentation. It is a defense mechanism of our skin to sun damage, and no matter what excuses you’ve heard, there is no such thing as a good tan.

The rationalizations you hear about “hitting the tanning bed to get a base so that I don’t burn” are far from truth. A sunburn is not necessary to do damage, as the effects of sun exposure add up. A sunburn is just a severe effect happening all at once.

UVA and UVB are both responsible again here. UVB does cause your skin to get thicker, which is somewhat protective, but not necessarily a good thing, especially cosmetically. Tanning beds do not elicit such protection, as most of them are UVA radiation now, which does not provide a protective mechanism. UVA, however, is responsible for photoaging, or that wrinkly, old look you start to see with chronic sun exposure. UVA creates such aging by penetrating deep into the skin and destroying our elastic fibers.

Mutation
UVA and UVB both cause damage to our cellular DNA, and with enough exposure our body isn’t capable of repairing it. That means one thing, the “C-word” discussed later.

SUNSCREEN
There are two main types of sunscreens: physical and chemical.

Physical sunscreens function to reflect light away. These are much less used—think of that lifeguard with the white zinc oxide on his nose. They are very functional, however, as they are broad spectrum and reflect all UVA and UVB wavelengths of light.

Chemical sunscreens function to absorb harmful UV radiation, in contrast to reflecting it away. Make sure your sunscreen protects against both UVB and UVA, as older sunscreens focused more on UVB, and now we know that UVA is responsible for a host of negative outcomes as well.

Sunscreens are classified by their sun protection factor (SPF), which indicates how much longer one who has applied sunscreen should be able to stay in the sun before getting a sunburn as compared to someone who hasn’t applied sunscreen. Protection is great, but remember that SPF is often overestimated due to inappropriate usage and dilution.

Another important issue for triathletes, to be sweat resistant, a sunscreen only has to protect after 30 minutes of sweating. How many workouts do you do under the sun that are shorter than 30 minutes?

The best advice is to apply liberally and often, but when you’re mid-workout, this is quite inconvenient. Your best bet is to stay as covered as you can tolerate with clothing or bring a spray sunscreen.

SWEATING
Sweating is a major part of our body’s ability to maintain body temperature. Our body has 2 to 3 million sweat glands, and they are the most concentrated on the palms and soles. Aha! An explanation for those sweaty palms!

The main type of sweat glands we think of are called eccrine glands. They secrete a dilute solution onto the surface of our skin that is higher in lactate than our blood plasma and lower in sodium and chloride than our blood. The composition of your sweat can change over time as your body adapts to different sweat demands—this is a major part of heat acclimatization.

On a fun (or not so fun) note, a different kind of gland, called an apocrine gland, exists only in our armpits and anogenital regions. Once we’ve been through that lovely timeframe known as puberty, apocrine glands secrete an odorless, oily substance. This substance is then degraded by bacteria that live on our skin, and voila! Stink. Body odor.

SKIN CANCER
Never a fun topic, but it deserves a mention here, as skin cancer is the most common human cancer. Over half of all new cancers are skin cancers. There are three common skin cancers, all of which are initiated and promoted by UV radiation. They are, from most common to least common:

Basal Cell Carcinoma
85 percent of these are found on the head and neck, areas of high sun exposure. The older you are, the higher your risk, and these can grow to be quite large and problematic. When caught early, these are easily treated by removal.

Squamous Cell Carcinoma
Here again, 85 percent of these cancers occur in sun-exposed areas. A pre-cancerous version of these can exist, called an actinic keratosis, which is just a discolored, scaly area of skin. Again, these can be taken care of if caught early, but if this one spreads, you’re in trouble.

Melanoma
Melanoma is the least common, but the most deadly skin cancer. Its incidence has tripled since 1980, and any given American has a 1 in 65 chance of getting melanoma. Melanoma is most common on our legs and back, areas of intermittent sun exposure. This suggests that infrequent, high doses of exposure (in these areas that don’t usually see the sun) are to blame. Melanoma can arise from normal moles called nevi, abnormal moles, moles present at birth and even from normal skin. Again, we have to be careful about this one spreading, and prognosis is dependent upon how deep it has penetrated upon discovery.

So, as the Australian campaign says: Slip, slap, and slop. Slip on a shirt, slap on a hat, and slop on some sunscreen to stay young, beautiful, and most important: healthy.

WORKS CITED

Colven, Roy. “The Skin.” HUBIO 567 Course Pack. Autumn 2006. University of Washington
Publication Services.

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Cameron Chesnut is attending medical school at the University of Washington. He has a background in sports nutrition and physiology, and he uses this knowledge to piece together the everyday medical mysteries of sport. Cameron is also an avid triathlete, having trained at the Victorian Institute of Sport in Melbourne, Australia and is currently preparing for Ironman Coeur d’Alene.

Cameron races to promote health care education and access; he is supported by GarageTown USA, Under Armour Performance Apparel and Pacific Elite Fitness.