Tingling in the legs while running or engaging in activities that activate your leg muscles occur when your leg nerves compress. This compression contracts the nerves, causing a tingling sensation. Numbness and burning accompany the tingling in severe cases.

Keeping fit during pregnancy can ease some pregnancy symptoms such as nausea and excess weight gain. It also can strengthen your body, which may make labor and delivery easier. Be sure to consult with your doctor to confirm that exercise during pregnancy is safe for you.

In-vitro fertilization, or IVF, is utilized by couples that are unable to conceive naturally. During the process, mature eggs are fertilized by sperm in a laboratory. The fertilized egg is then implanted in the uterus. According to MayoClinic.com, IVF is the most reliable form of assisted reproductive technology.

A clicking sound in your head when you run most likely results from tinnitus. Tinnitus is a symptom of other conditions such as hearing loss and jaw-joint disorders; it produces sounds such as ringing or clicking in your ears and head.

As a woman, your heart rate changes as you age. These changes in heart rate affect how fast your heart beats at rest and during activity. Among the reasons for knowing your heart rate is that it is an indicator of cardiovascular health.

Athletes and exercise enthusiasts looking to maximize their fitness efforts can utilize heart rate monitors to evaluate their energy expenditure. Among a crowded field of options, Polar heart rate monitors are often ranked at the top.

A normal resting heart rate is somewhere between 60 and 100 beats per minute. Many factors can influence your heart rate, including your emotions, temperature, body position, physical activity, body size, level of fitness and the food and drink you consume.

The average heart at rest beats about 60 to 80 times a minute, and gets slightly quicker as you age. Prescription medications can lower a heart rate that beats dangerously fast. Doctors also have a technique (which can be dangerous outside of a medical setting) called carotid sinus massage to stop a racing heart.

Heart rate is a measure of how hard your heart is working and thus helps people determine the intensity of a particular workout. When you work your body harder, your heart beats faster and your body turns to different fuel sources when working at various levels of intensity.

Certain foods can speed up your heart rate and make it feel as if it is racing. If you ingest something that has a stimulative effect, your heart gives a "fight or flight" response, much as it would in response to exercise, fear or anger.

Your pulse starts in your heart, with your heart beat. Every heart beat causes a pulse in your arteries, similar to the ripple a stone makes when it is thrown in a pond. Your heart rate is the number of times your heart contracts (beats) in one minute.

Rest the index finger and middle finger of one hand on the inside of the opposite wrist and you'll feel an artery throbbing under your fingers. To measure your heart rate, or pulse, count the number of throbs in a minute.