CHAFING
Skin-to-skin and skin-to-clothing rubbing can cause a red, raw rash that can bleed, sting, and make you yelp during your postrun shower. Moisture and salt on the body make it worse. Underarms, inner thighs, along the bra line (women), and nipples (men) are vulnerable spots.
PREVENT IT
Wear moisture-wicking, seamless, tagless gear. Fit is important—a baggy shirt has excess material that can cause irritation; a too-snug sports bra can dig into skin. Apply Vaseline, sports lube, Band-Aids, or NipGuards before you run. And moisturize after you shower. "Drier skin tends to chafe more," Papadeas says.
TREAT IT
Wash the area with soap and water, apply an antibacterial ointment, and cover with a bandage. If you're wearing sports lube and quality clothing and are still experiencing redness, visit a dermatologist. Dr. Adams says it's very common to mistake a fungal infection for chafing.
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RUNNER'S TOES
During flip-flop season, it's easy to pick out distance runners. Many marathoners and ultrarunners have discolored toenails, since the more miles you log, the more likely you are to bruise your nails. Lots of downhill running and too-small shoes can exacerbate the issue—both cause your toes to slam into the front of your shoe. Biomechanics are a factor, too. "Some runners pull their toes up while running," Williams says. "If the toes are chronically lifted against the upper toebox of the shoe, it can cause toenail irritation." Also, Williams says an unstable big-toe joint can make the other four toes grip too hard (and bruise) upon landing.
PREVENT IT
Wear properly fitted shoes and trim nails regularly. "Long nails get injured more easily," Williams says.
TREAT IT
A bruised nail usually heals on its own within six months. If it's really painful, see a podiatrist who can drain fluid from under the nail. Also, if it's a chronic problem, a sports podiatrist could help you determine if toe-lifting and toegripping are to blame, in which case an orthotic may be a fix.
SUNBURN
Not only can the sun's rays cause redness, pain, swelling, and lasting damage, studies show that athletes who train outdoors (unsurprisingly) may have a higher risk of developing skin cancer.
PREVENT IT
Avoid the sun between 10 a.m. and 4 p.m., wear a hat, run in the shade, and wear sunscreen. Because sunscreen can't withstand prolonged exercise, stash some in your pocket or circle back to your car so you can reapply every hour, Dr. Adams says. You can also wear technical apparel that blocks UV rays. If not, wear darker colors, which block more UV rays than light colors, and wash clothing with detergent (like SunGuard) that protects against damaging rays for up to 20 washings.
TREAT IT
Taking an anti-inflammatory and applying aloe vera a few times a day will take the edge off the pain.
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Feel Better
Opt for thin socks over thick ones in the summer. Socks with extra cushioning are comfy, but they trap moisture, leading to blisters and athlete's foot.
DEFENSE STRATEGIES
Skin-care supplies all runners should stash in their gym bag or car:
1. Bodyglide or vaseline
Prevents chafing and blisters.
2. Antiobiotic ointment
Keeps chafing wounds and popped blisters from getting infected.
3. Sunscreen
Prevents sunburn. Apply sweat-proof formulas with an SPF of at least 30.
4. Antifungal ointment
Treats and soothes athlete's foot.
5. Moleskin
Covers hot spots to prevent blisters from developing.
6. Antifungal powder or spray
Helps to prevent athlete's foot.
7. Aloe vera
Soothes sunburn and helps damaged skin heal faster.
8. Band-aids
Use to cover popped blisters or apply to areas where you tend to experience chafing.