Why running injuries happen
Running is a great way to stay fit and improve your health, but it also carries a risk of injury. The most frequent running injuries are shin splints, stress fractures, and plantar fasciitis, and most of these overuse injuries result from increasing mileage too quickly, not giving the body enough time to recover, or having tight or weak muscles.
Stress fractures
A stress fracture is a break in a bone, usually in the lower leg or foot, that occurs when a change in activity causes normal pressure on the bone to exceed what the body's own bone-remodeling process can keep up with. This kind of over-pressure can come from increasing an activity's intensity too quickly, changing surfaces, or using inadequate equipment. Other risk factors include anatomical issues like bunions and blisters, muscle weakness or imbalance, and poor flexibility. Female athletes are especially vulnerable due to the female athlete triad, which includes lower bone density and hormonal changes tied to menstruation, and anyone with osteoporosis or another bone-weakening condition may be at even greater risk.
Stress fracture symptoms typically start as sharp, shooting pain that's worse at the beginning of an activity and eases during training or rest, but runners who push through this discomfort can develop chronic symptoms that require medical treatment.
Plantar fasciitis
Plantar fasciitis causes pain at the bottom of the heel or arch, occurring when the plantar fascia, the band of connective tissue running from heel to toes that absorbs shock and supports the arch, becomes inflamed from excessive pressure or damage. People with high arches, flat feet, or overpronation have a higher chance of developing it. Symptoms typically start as a stabbing pain on the bottom of the foot near the heel, often more intense first thing in the morning or after standing for a long time.
Hamstring strain
A hamstring strain, or pulled hamstring, happens when one or more of the three muscles running down the back of the thigh, the biceps femoris, semitendinosus, and semimembranosus, gets stretched too far. It can range from mildly painful to a full tear at its origin, and strains are graded by how many muscle fibers are injured. Grade 1 is mild, causing a twitch or jerk when pushing off or stretching the leg. Grade 2 is more serious, with intense, immediate pain that worsens with movement, difficulty walking, and sometimes visible bruising. Most hamstring strains heal with rest, ice, compression, and elevation, but severe pain or weakness is worth a visit to your healthcare provider.
Runner's knee
Nearly 40% of running injuries involve the knee, and the most frequent is runner's knee, or patellofemoral pain syndrome, typically caused by misalignment of the knee joint from injury or leg length differences, which causes the kneecap to rub unnecessarily and wear down cartilage. Iliotibial band syndrome is another common cause of knee pain and inflammation, with symptoms including a tight feeling on the outer thigh, stiffness in one leg, and an urge to shift weight off of it.
Runner's knee is typically treated with rest and anti-inflammatory medication, but if pain or swelling doesn't improve, it's time to see a physical therapist, who can recommend safe exercises to reduce symptoms and support overall knee health.