Running may seem like a simple activity, one that results in many health benefits, but it can bring with it the risk of related injuries. This is especially true during the warm summer months, when outdoor running is more pleasurable. Fortunately, proper training can help to reduce this risk.

Mononucleosis--often known simply as “mono”--has an incubation period of one to two months. Once symptoms appear, recovery can take an additional four to six weeks. Until your physician tells you it is safe to resume more strenuous workouts, avoid any but the mildest exercise (e.g., short walks).

How much exercise is enough? There is no one answer. Age, sex and current fitness level, along with risk factors such as diabetes, heart disease, stroke and excessive weight, must be factored into the equation. All of these considerations may make it impractical to compare various fitness programs. But the following guidelines can help you reach your goals.

Because recovery from surgery to repair flexor tendons (the tendons that control the movement of your fingers) can be challenging and slow, many people become frustrated after about two months. Why does it take so long to regain the ability to fully bend or straighten your finger?

Sprained ankles may be common, but they can lead to long-term problems. A European study found that up to 75% of the sprains incurred by professional soccer players occurred in ankles with previous sprains or instability. Another study reported that up to 40% of people who had previously sustained an acute ankle sprain were likely to experience chronic ankle instability.

If you are about to have your hip replaced, you will need to begin a rehabilitation program very soon after the procedure is completed. The type of rehabilitation will vary with the surgical technique used to attach the metal prosthesis to the femur. This artificial ball and stem can be affixed either with bony cement called methylmethacrylate or a “cementless” prosthesis with microscopic pores into which bone from the femur grows.

Strength training has benefits for all ages, but it can be a neglected part of an exercise regimen for men and women aged 50 years and older. Research suggests that when performed correctly, strengthening exercises are a safe way to improve fitness and health, even in older adults who have health conditions such as arthritis.

Systemic lupus erythematosus (SLE or lupus) is a chronic, autoimmune inflammatory disease that can affect almost any organ system in the body. It most often develops in women during their childbearing years. Currently, there is no cure for lupus, but treatment can reduce symptoms. These frequently occur in a cycle of flare-ups and remissions.

Rotating or twisting an ankle or foot or incurring a crush injury by dropping a heavy object on the foot may cause a fracture of the fifth metatarsal, a bone at the base of the small toe. This injury, also known as dancer's fracture, is similar to a sprained ankle in that it can make walking difficult, will cause some localized pain and swelling, and the skin can turn black and blue. However, the good news is that, with proper treatment and therapy, an individual with a dancer's fracture can start bearing weight on the injured foot fairly quickly.

A recent study found that about 25% of the U.S. population has flat feet, and almost 43 million Americans suffer from foot problems. Flat feet, a condition in which the foot does not have a normal arch when standing, can present challenges for a running program, but having flat feet does not mean that such vigorous activities are out of reach. Although flat arches may create pressure with some foot movements, you need not stop running.