Marathons are an incredible testament to what the human body can endure, not some big scary race we should be afraid of. Sure, you may feel exhausted and sore, but that doesn’t mean you have to be an Olympic-level athlete to cross the finish line. However, it is essential to be mindful of certain health precautions beforehand.
Health Risks to Consider Before Training for a Marathon
Before signing up for a race, talk to your primary care provider (PCP). They can evaluate any health concerns you may need to address, help you control many conditions, and connect you with providers who specialize in those conditions.
Some common conditions that affect runners are:
- Untreated eating disorders: Running with an untreated eating disorder can increase the risk of an irregular heart rhythm, or cardiac arrhythmias. Meeting with a dietitian or a mental health care provider can ensure runners receive the nutrients they need to exercise safely.
- Existing bone or muscle injuries: A sports medicine doctor can evaluate whether a bone or muscle has fully healed. A return to running too quickly can lead to re-injury. Too much force on a sprained ankle, for example, may lead to a complete bone break.
- Underlying heart conditions: Your PCP may refer you to a sports cardiologist if you have untreated high blood pressure, a family history of heart disease, or an unexplained early death of a first-degree family relative. Sports cardiologists can teach runners how to manage a heart condition throughout the race.
- Asthma: Exercise may induce asthma, a chronic condition that restricts the airway. Using a prescribed inhaler before running can help relieve some symptoms.
How Marathon Running Can Affect Key Organs
- The brain: Running can improve your mental health. The brain releases chemicals that trigger a “runner’s high,” which may help you think more clearly. However, fatigue can disrupt a runner’s focus over the course of a marathon and erode their motivation to finish. Sweating and dehydration can lower the amount of sodium in the blood, too. Sodium is an electrolyte—an electrically-charged mineral dissolved in water—that promotes nerve function. The brain is sensitive to low sodium levels. Drinking too much water or overhydrating during a marathon can result in low serum sodium, referred to as hyponatremia. Low enough levels of sodium may trigger feelings of sluggishness or confusion from the brain. This can result in death if not detected and treated.
- The kidneys: In addition to sodium, the body relies on several other electrolytes for vital functions. The heart, for example, relies on just the right amount of the electrolyte potassium to create a heartbeat. Too much, or too little, can harm the heart. The kidneys help strike a balance by filtering electrolytes and water from the bloodstream. Dehydration forces the kidneys to preserve this balance by withholding water they normally dispose of in the form of urine. Overhydrating, on the other hand, can diminish electrolyte concentrations, forcing the kidneys to produce more urine. Runners who drink too much or too little water can place unnecessary stress on their kidneys.
- The heart and lungs: These work together to deliver oxygen throughout the body. Oxygen regulates body temperature, converts food into energy, and removes toxins. The heart-lung tandem works much harder during intense activities.
- The joints (the space between bones): Exercise can keep cartilage—the padded lining between bones—healthy. That said, running with an underlying joint condition, such as arthritis, can do more harm than good to the hips, knees, and ankles.
- Bones, muscles, and ligaments: Unhealthy bones, muscles, and ligaments (tissue connecting one bone to another) can’t sustain the same amount of force as they can when healthy. Too much force may cause a bone to fail, usually in the form of a bone stress injury or a stress fracture. It can also injure a tendon or sprain a ligament. Overexerting muscles in the lower body can also lead to painful muscle strains and cramps too. Age-related changes to tissues may occur over time. A runner typically experiences damage to these tissues as pain is confined to a specific location.
Warning Signs
Pay attention to your body throughout training, even if you don’t have a known underlying condition. Keep an eye out for:
- Pain that builds: Bone stress injuries can occur from improper running technique. If pain worsens in a specific area of the lower body—particularly if localized to a bone—stop running and see a sports medicine doctor. Pain may feel most noticeable when hopping on one leg. Swelling in a joint, or other mechanical symptoms associated with pain, can signal a joint injury. Painful sensations, or a loss of
- sensation, in the lower body can signal injuries to nerves that need evaluation.
- Dizzy spells: Feelings of light-headedness can occur from dehydration. The American Council on Exercise suggests drinking eight ounces of water 20 to 30 minutes before exercise. However, many runners will drink fluid regularly and can overhydrate. If light-headedness persists and chest pain occurs, see a sports cardiologist. It may signal an irregular heart rhythm. Some smartphone apps and wristwatches can detect an irregular heart rhythm and track heart rate.
- Heart rate: You can roughly determine where to keep your maximum heart rate at by subtracting your age from 220. Of course, many different factors can affect heart rate, such as family history, medications, and even temperatures, so this should not be taken as a perfect science, either. Near-fainting spells and repeatedly occurring palpitations can signal a more serious heart rate problem that needs medical attention.
Running 42.2 kilometres is no small feat and can feel incredibly rewarding, so celebrate the accomplishment. After completing the marathon, keep moving, but avoid completely stopping all physical activity. Low-impact exercises, such as cycling, walking, or swimming, can help muscles heal. If pain does not improve or prevents you from walking or bearing weight after a couple of weeks, see a medical professional immediately, as this can be a sign of a bone stress injury. Take some time for yourself before attempting your next marathon.
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