When you’ve suffered from chronic knee pain, a knee replacement can give you a new lease on life, but hearing clicking noises coming from the joint may give you pause. Certain exercises will keep your knee functioning at its highest level and may quiet some of the noises.

High heels can not only be painful, but also cause health problems. Here's a guide to help you choose heels that won't hurt.

Your respiratory system controls your breathing and begins when you draw in air through your nose or mouth. The air travels through your windpipe into both of your lungs, where small air sacs capture oxygen and distribute it in your bloodstream through small blood vessels called capillaries.

From infancy to late life, nutritional needs change. Children must grow and develop, while older adults must counter the effects of aging. The importance of age-appropriate nutrition during all stages of the life cycle cannot be overlooked.

Taking a deep breath and experiencing right-sided chest pain provokes physical discomfort and anxiety. Chest pain brought on or worsened by forceful breathing is called pleuritic chest pain. This symptom typically originates from an infection, injury or other condition affecting the right lung or chest wall.

Tightness in your knees can be irritating since it interferes with simple tasks like walking and sitting. The sensation of tight knee tendons is often due to tightness throughout the muscles that are connected to tendons.

The tibialis posterior muscle is the leg muscle that points the foot down and in, and it plays a key role in keeping the arch of your foot stable during walking and running. Problems with this muscle can present themselves as pain on the inside of the ankle, a collapsing arch or difficulty standing on your toes.

Bacteria are all around us, in the air, on objects and normally found in and on the human body. When bacteria is on the human body in the absence of disease, it is called a colonizer.

A new study shows that American's are getting "shorter" while other countries in the world continue growing to new vertical limits.

Bladder irritation can occur on a temporary or long-term basis. Short-term causes include urinary tract infections, recent childbirth or catheterization.

Driving requires a person to integrate information from multiple visual and auditory sources. Visual information that needs to be processed includes activity on the road, your mirrors and the instrument display. Similarly, auditory information includes sounds made by your car, other cars and pedestrians.

The blood-brain barrier prevents toxic substances, large molecules, and neurotransmitters released in the blood from entering the brain. Four areas of the brain are not protected by the blood-brain barrier.