3. Why do I get so antsy during a pre-race taper?That two-week-ish span where you cut back training volume by about 50 percent gives you time to recover and to become mentally and physically stronger. You probably haven't felt well-rested in weeks. "Runners typically aren't used to having all that energy," says Larry McDaniel, associate professor of physical education at Dakota State University in Madison, South Dakota. "The body gets accustomed to fatigue as a 'normal' state."
Your mind is probably on overdrive, too, thinking about your highly anticipated race day. "A fresh body, coupled with nerves and excitement, can drive you—and those around you—crazy."
Running Rx: Take 10 minutes to visualize the race, and then try not to think about it for the rest of the day. See a movie (avoid Chariots of Fire); read a book (stay away from Born to Run); grab a beer with a non-running friend; do some gentle exercise if you must. "I always find that a walk takes the edge off ," says McDaniel.
More: 6 Yoga Poses for Runners
4. Why do the nipples of some male runners bleed during a marathon, but those of females don't?
Karmic payback for women transporting two bouncing cantaloupes for 26.2? Okay, maybe not. Sweat is a mix of water, salt, and a handful of other minerals. When the water evaporates, you're left with abrasive salt on your nipples, which are front-and-center in a high-sweat zone.
"After a few hours, a shirt rubbing against that salt feels like sandpaper," says Dr. Bright, adding that beginner male runners are most susceptible because men typically sweat more than women, and novices take longer to complete a race. The abrasion causes chafing, which causes bleeding, which causes red stripes down the front of a white shirt, especially near the end of marathons.
Women aren't immune. Even nursing moms can be afflicted. "The skin around your nipples isn't capable of thickening and getting stronger," says Dr. Bright, medical director for the Columbus Marathon. The few women he has seen with bloody nipples were wearing no bra, a poorly fitting bra, or a cotton one.
Running Rx: Stay hydrated. "When you stop sweating, all you have left on your skin is salt," says Dr. Bright. "The liquid takes the edge off the salt." Equipment fixes for men: Protect your teats with circular Band-Aids or NipGuards. Women? A moisture-wicking, properly fitted sports bra.
5. Why does the inside of one ankle get bloody from being hit by the opposite heel, but not the other?That red tattoo is called a heel whip, and it's from excessive rotational motion of your foot. Instead of your foot traveling in a forward plane, it makes an arc, causing your heel to nick your anklebone. It doesn't have to be gory: Heel whips can also just dirty your inside shin. "The extra torsion can be caused by anything from the alignment in your ankle to a hip issue," says Dicharry, who adds that one side usually bears the bloody brunt because of muscular imbalances.
Running Rx: Think about pushing off through the big toe, not the pinky toe, so that your foot swings cleanly forward, and you'll whip your ankle less. If you need more than just a Band-Aid after a run (e.g., ice packs and Advil for various parts of your lower body), a visit to a physical therapist will help you determine whether you have strength imbalances that can be corrected with single-leg exercises.