Aerobic—has to do with oxygen use. Aerobic exercises are those in which your muscles use oxygen to burn fuel for energy. Because your heart and lungs provide oxygen to the muscles, aerobic exercise is also called cardiorespiratory conditioning.

Anaerobic—without oxygen. Anerobic exercises require your body to function beyond its aerobic capacity and use alternate, non-oxygen pathways to burn fuel. Anaerobic exercise can only be performed for short periods of time, and is usually alternated with rest periods or aerobic activity. Anaerobic activities build muscle strength and increase glycogen reserves.

Body Composition—the amounts of various types of tissue in the body, including muscle, fat, bone and water.

Body Mass Index (BMI)—a ratio that indicates the percentage of an individual’s body weight that is fat. Usual measures of BMI may not be accurate in exceptionally fit individuals.

Calorie—a unit of measurement of energy. Generally speaking, we use the term to refer to the energy in food or to energy used during activity.

Carbohydrate—one of the three macronutrients. Carbohydrates supply energy.

Cool down—a period of slower-paced exercise following an aerobic workout, usually lasting 5-15 minutes. It allows the body to gradually return to its pre-exercise state.

Dehydration—loss of body water. Loss of body water during exercise is usually due to sweating and increased respiration, and inadequate fluid replacement.

Duration—the time length of an exercise session; how long it lasts.

Endurance—your ability to exercise for a period of time without undue fatigue. Sometimes broken out into muscle endurance and cardiorespiratory endurance.

Fat—one of the three macronutrients. There are several kinds of fats; some are healthy and some are not.

Fitness—the ability to perform activities without excessive fatigue. The components of fitness are cardiovascular fitness (ability of the heart and lungs to supply oxygen to the muscles), muscle strength and endurance, flexibility and body composition.

Flexibility—the ability of joints and their corresponding muscles to bend and stretch.

Glycogen—a carbohydrate that serves as short-term energy storage. Glycogen is primarily found in muscles and the liver.

Hydration—the amount of water in your body. Adults are 40-60 and 70% of your maximum heart rate.

Warm up—a period of 5-15 minutes prior to aerobic exercise where you gradually increase the rate of exercise to allow muscles to warm up.