Here's what to expect from a fitness test

Before you start an exercise or weight loss program, you may want to have a fitness test to evaluate your current status and to examine improvement as you progress through the program. If you join a gym, a fitness assessment may be required. This is smart, since a fitness test is important for determining a safe and effective exercise recommendation. A fitness test should include measurements of muscular strength, aerobic fitness, flexibility and body composition.

Muscular strength is measured using a one-repetition max (1-RM) test in which the heaviest weight you can lift is determined, typically for the bench press and the leg press. Sometimes alternative tests are used, such as the number of push-ups or sit-ups you can do. Handgrip strength can also be used as a rough estimate of overall muscular strength.

Cardiorespiratory or aerobic fitness is the ability of your heart and lungs to supply oxygen to your exercising muscles. The "gold standard" is to actually measure the amount of oxygen you breathe during vigorous exercise, called maximal oxygen uptake or VO2 max. This test requires specialized equipment that is typically only available in exercise labs, so most fitness tests estimate VO2 max.

Your aerobic fitness test will probably be a submaximal test in which your heart rate is measured as you exercise at several intensities on a treadmill or stationary cycle. The change in your heart rate is used to estimate your VO2 max. This value is used to determine the intensity at which you should exercise and can be monitored by checking your pulse or by wearing a heart rate monitor.

Flexibility is an important, but often overlooked, component of fitness. Flexibility is usually measured using the sit-and-reach test which measures low back and hamstring flexibility.

Body composition refers to your percent fat, which is of interest to people who want to lose weight or build muscle. The most common method of measuring percent fat is skinfolds, in which the thickness of your skin and subcutaneous fat is measured at several sites on your body. The most important criteria for accuracy of skinfolds is the skill of the tester, so look for someone who has years of experience to measure your skinfolds. There are more accurate methods of measuring percent fat, but they are limited to research and clinical purposes.

Simpler methods of assessing your body weight and fatness include body mass index and circumferences. Body mass index can be calculated from your height and weight (look online for a BMI calculator) and is widely used to evaluate body weight and health. Waist and hip circumferences are determined using a measuring tape and provide more information about where fat is stored. Upper body fat (high waist circumference) is associated with higher health risk than lower body fat (large hip measurement). As you lose weight, you should see changes in your weight as well as waist and hip circumferences.

There are two additional points to remember before you have a fitness test or start an exercise program. First, you should see your doctor if you are new to exercise or have had changes in your health. Second, a fitness test should be conducted by a qualified professional. Make sure the personal trainer or fitness professional you work with is certified and has experience working with clients like yourself, whether you are young and fit or older and out of shape.

Brian Parr, Ph.D., is an associate professor in the Department of Exercise and Sports Science at USC Aiken where he teaches courses in exercise physiology, nutrition and health behavior. He is a member of the American College of Sports Medicine and is an ACSM certified clinical exercise specialist; his research focuses on physical activity in weight management and the impact of the environment on activity and diet. Parr lives in Aiken with his wife, Laura, and sons Noah, Owen and Simon.