Hitting “The Wall”
Hitting “the wall” or “bonking” is one of the most common experiences among marathoners, especially beginners. You hit the wall when your liver and muscle glycogen stores become depleted—an experience characterized by feelings of sudden and profound fatigue, or loss of energy, and pain. According to New Scientist, more than 40 percent of runners will hit the wall during a marathon. You may be able to prevent this by ensuring that your glycogen levels are high before your event, maintaining proper glucose levels during your marathon and keeping your exercise intensity at an appropriate level throughout your race.
Metatarsal Stress Fracture
Metatarsal stress fractures are an unfortunate -- and often preventable-- phenomenon among some marathon runners. The pain associated with metatarsal stress fractures usually arises on the top of your forefoot, not the bottom of your forefoot. A 2010 study published in the “Clinical Journal of Sports Medicine” states that poor training technique and other risk factors may contribute to lower-limb overuse injuries in runners that affect muscle, tendon and bone health. Bone-related injuries, notes the study, range from stress reactions (the very early stages of a stress fracture) to full-fledged stress fractures. According to Marathon Guide, the more fatigued your lower extremity is, the greater your risk for a stress fracture.
Nipple chafing is an undesirable (and painful) problem that happens to some -- mostly male -- runners during a marathon. Nipple chafing and bleeding occurs when your shirt rubs against your chest over time, causing repetitive friction that irritates your sensitive nipple tissue. Sports bras typically prevent chafing in women. Nipple chafing may be prevented by wearing shirts made of soft material or creating a barrier between your shirt and your nipples. According to Dr. Lewis G. Maharam in an article from the "New York Daily News", removing nipple jewelry, hydrating properly, and wearing softer, looser shirts (especially shirts made of synthetic sweat-wicking fabric) can help prevent nipple bleeding during a marathon. Using lube or protective bandages over your nipples can also be helpful for this purpose, notes Maharam.
Ill-fitting shoes, especially shoes with tapering toe boxes, may cause toenail problems that arise during or after your marathon. Jeff Galloway, an American runner and Olympian, notes that if your toes undergo sustained pressure from tight shoes or socks, you will experience friction between your toenail and its surrounding tissue. This friction can lead to fluid accumulation and pressure under your toenail that causes a blackening of your toenail and eventual toenail loss—a process that can take up to several months. Galloway notes that you can decrease your likelihood of a black nail by using shoes with roomier toe boxes.