1. Sun sense. Although most people enjoy being in the sun, it’s important to remember that excessive exposure to the ultraviolet rays (UVA and UVB) of the sun can be harmful in several ways. For example, UVA rays can bring about premature wrinkling, whereas UVB rays are the primary cause of sunburn. Collectively, UVA and UVB rays can give rise to skin cancer.
2. Time and place matter. When and where you’re at when you’re exposed to the sun can impact the extent of your exposure to the sun’s rays. For example, the sun’s rays are most intense from 10 a.m. to 2 p.m. As such, you should schedule your outdoor activities before or after that period. In addition, the effect of the sun’s rays is heightened when you are on or around sand, snow, or water, or are in an area of high altitude.
3. Protect yourself. One of the most effective ways to combat the possible damage that the sun can do to your skin is to use a sunscreen or a sunblock. Although sunscreens and sunblocks are usually either lotions or sprays, they work in vastly different ways. Sunscreens, for example, contain chemicals that specifically prevent sun rays from penetrating to your skin. Sunblocks, on the other hand, serve as a physical barrier to reflect and scatter the rays of the sun.
4. Dress for the occasion. You can shield yourself from most of the sun’s harmful rays by dressing appropriately. In this regard, clothes with thick, tight weaves tend to provide the best coverage. It is important to keep in mind when you’re around water that t-shirts will typically lose a substantial portion of their ability to protect you from the sun when they become wet.
5. Skin’s best friend. The sun protection factor (SPF) number details the degree to which a particular sunscreen or sunblock will protect an individual from burning. The higher the SPF number, the greater the level of protection. As a rule of thumb, an SPF of 15 or greater is recommended for use by all skin types, except those who have a very fair or fair complexion. These individuals should use an SPF of 30 or more.
6. Especially vulnerable. Children are particularly susceptible to exposure to the sun. Children who have sunburns can face a greater risk of incurring skin cancer later in life, including melanoma. As such, parents should closely monitor the amount of time their children spend in the sun and ensure that they avoid being outdoors when the sun’s rays are especially intense. They also should encourage their children to use sunscreen or sunblock when they play outside. Sunscreen should not be used on babies or toddlers under the age of one year. Rather, because these children have very sensitive skin, they should simply be kept out of the sun.
7. False sense of security. Even if you use sunscreen to protect yourself, you should not stay in the sun for an extended period. The ingredients in sunscreens do not offer unlimited protection against all of the potential negative effects of excessive exposure to the sun. For example, evidence shows that sunscreens do not entirely preclude the interference of sunlight with the body’s immune system.
8. Unseen danger. It is important to be aware of the fact that most of the sun’s UV rays penetrate clouds. As such, because your skin is at risk even on hazy overcast days, you should wear sunscreen or sunblock if you plan on being outdoors for more than a few minutes.
9. Drenched in reality. Individuals who spend time in the water are not immune from sun damage. In reality, the UV rays of the sun can penetrate at least 3 feet of water. As such, swimmers should put on sunscreen before they go into the water, and then reapply it after they’re done swimming. They also can further protect themselves by wearing a white or pastel swimming suit, which will help to reflect - rather than absorb - the sunlight.
10. A searing experience. One of the more common consequences of too much sun or sun-equivalent exposure is sunburn. Sunburn literally involves a burn to living tissue that results from overexposure to the UV rays of the sun. Mild sunburn (e.g., redness of the skin) is usually treated with a combination of taking a cool bath or shower, applying a hydrocortisone cream, and taking aspirin or ibuprofen. More serious cases of sunburn (e.g., chills, fever, nausea, etc.) should be referred to a physician.
James A. Peterson, Ph.D., FACSM, is a freelance writer and consultant in sports medicine. From 1990 until 1995, Dr. Peterson was director of sports medicine with StairMaster. Until that time, he was professor of physical education at the United States Military Academy.
Copyright 2010 by the American College of Sports Medicine.