What should I look for in buying a pedometer?
Is there any way to test a pedometer for accuracy once I have one?
Is there such a thing as proper fitness walking technique?
What should I look for in buying an exercise video/DVD?
I used to be very active and fit, but now I have no time to exercise. What type of program can I do that takes very little time?
Do weekend warriors die prematurely?
What about healthy young athletes who die during exercise?
Does exercise affect longevity?
Do I need to join a gym or buy exercise equipment in order to build fitness?

What should I look for in buying a pedometer?

Pedometers work by detecting body movement to count the number of strides you take by walking or running. Many pedometers also attempt to measure the amount of distance you travel by walking or running by multiplying the number of strides you take by your estimated stride length. Stride length varies from stride to stride, so the distance recorded by the pedometer is approximate. The most accurate approach in using your pedometer is probably to focus on increasing the number of strides you take per day. With this in mind, you want to purchase a pedometer that counts steps accurately.

          Different types of pedometers may be more accurate measuring strides during slow walking or at a quicker pace. Some click more loudly than others—you may find the noise to be an unpleasant distraction or a positive motivator. Choose the type of pedometer that will work best for you. Some of the more expensive pedometers also include other features, such as heart rate measurement or calculation of approximate calories burned; think carefully about what features you will really need—and need to pay for. Research has not found pedometer measurement of calories burned to be accurate.

          New pedometer models are being released all the time. Consumer and fitness magazines and organizations rate pedometers for accuracy; check out Consumer Reports or the ratings at walking.about.com for advice and reviews. If possible, check the accuracy of a pedometer before purchasing it (see next question).

Is there any way to test a pedometer for accuracy once I have one?

Pedometers typically measure stride frequency with a pendulum (each stride moves the pendulum one time) or accelerometer (electronically measures leg movements). You can check stride accuracy by taking 100 strides and comparing it against the reading on the pedometer. Do this test at different walking speeds; you may find that the pedometer is more accurate when you are walking steadily at a relatively quick pace and less accurate when you walk short distances over the course of your day (around your residence or office, for example). If you are using your pedometer to also track distance traveled, you can measure distance accuracy on a standard 400-meter track (4 laps are about equal to a mile).

          When using a pedometer, there are several techniques that can help increase its accuracy. Attach the pedometer securely at your waistline, directly above your knee. Most pedometers need to be attached in an upright position, perpendicular to the ground. Don't attach the pedometer to loose clothing; if it flops around, the count will be less accurate. Check the position of the pedometer regularly over the course of the day and adjust it as needed.

Is there such a thing as proper fitness walking technique?

Yes. Most of us have a natural way of walking that we practice with no thought. But efficient fitness walking technique may differ slightly from your slower-paced walking technique. A check of your walking form may help boost walking efficiency and reduce the risk of injury. Consider having a friend watch you walk and compare your walking form to the following guidelines:

• Keep your head up and your eyes looking ahead.
• Relax the muscles of your face, shoulders, and hands; don't clench your fists.
• Keep your arms near your sides, with elbows bent at about 90 degrees. Your arms should swing freely from the shoulders forward and back; they should not cross in front of the body during the forward swing.
• Hold your chest up and tuck your hips slightly forward to help maintain un upright posture. Lean forward very slightly from the waist.
• Move and lift the upper leg naturally from the hip; swing the lower leg forward.
• As you step forward, your heel should land firmly on the ground first, followed by the ball of the foot. Push off from the ball of the foot and toes. Take care not to over- or under-stride. If your walking movement feels awkward, try slightly shortening or lengthening your stride.

If you are the type of person who prefers to exercise at home—and can stay motivated to do so—then an exercise video/DVD may be a good choice for you. Home workouts can be a good option for people with busy schedules or those who live in areas where weather or safety limit outdoor exercise. You may be able to find a single video that develops all the components of health-related fitness or you may need several featuring different activities in order to put together a complete program.

          Many exercise DVDs are produced by Hollywood celebrities or fitness models. That doesn't mean they aren't valuable—but it also doesn't guarantee quality. Many celebrity videos rely on expert consultants to ensure scientific accuracy. Make sure a video was evaluated by an experienced exercise physiologist or physician with knowledge about exercise. A UCLA study found that 60 percent of personal trainers in their study couldn't pass a basic test about human physiology, biomechanics, and elementary exercise techniques. Many of the trainers in the sample had more than five years experience in the field. Trainers who passed the test usually had degrees in exercise physiology or physical education. Likewise, the people providing the content of an exercise video should have formal training in the field. Some programs may feature both a celebrity and a certified instructor.

          Many places than rent videos and DVDs include exercise videos in their offerings, so you may be able to try out several at home before making a final selection. Choose a video featuring an activity you like, done at an appropriate level of difficulty. Make sure you have enough space to safely perform the activities on the video and that you have any needed equipment. Also check that you find the style of music appealing.

          Safety is a key consideration. The workout on the tape should include a warm-up and a cool-down. There should be modified exercises or techniques for people at different fitness levels. The workout shouldn't push you to perform beyond your current fitness level but should be able to accommodate you as your fitness improves.

          If you have any special health concerns, are exercising for the first time, and/or plan to try a new type of activity, such as Pilates or yoga, a good first step might be to take a class from a qualified instructor. Once you know basic safe exercise technique, then an at-home program using an exercise tape or DVD might be a good choice for you.

Most Americans are trying to include more activities in their daily schedule. People want exercise programs they can do quickly but that also build many fitness components. New research shows that high intensity training builds fitness in a remarkably short time. Develop fitness quickly by training at 90 percent of maximum during aerobic exercise and resistance exercise about three days per week. If you move quickly with little rest between exercises, you can develop high levels of fitness training 40 to 60 minutes, three times per week. This is not the ideal way to train, but this is a good compromise for people who are relatively fit but have little time for exercise. A typical "high speed workout" might include a 20-minute run at 90 percent effort, followed immediately by a weight training workout consisting of 8 exercises that work the major muscle groups.

How much exercise does the USDA recommend?

The new exercise recommendations from the USDA will be a challenge to most Americans. They recommend at least 30 minutes of moderate-intensity physical activity on most days of the week if the goal is greater health and the prevention of chronic disease. People should exercise moderately to vigorously for 60 minutes per day to prevent weight gain and 60 to 90 minutes a day to maintain weight loss. Physical activity should include aerobics, strength training, and flexibility exercises. Achieve physical fitness by including cardiovascular conditioning, stretching exercises for flexibility, and resistance exercises or calisthenics for muscle strength and endurance. Children should exercise at least 60 minutes every day. For more information, visit the website for the 2005 Dietary Guidelines for Americans (www.health.gov/dietaryguidelines).

Do weekend warriors die prematurely?

Many studies have found that regular exercise reduces the risk of premature death. People who exercise intensely tend to live longer than those who trained moderately or not at all. Weekend warriors exercise occasionally. Are they at greater risk of premature death or does sporadic exercise offer some protection? Harvard researchers compared the relative risk of death in weekend warriors (those who train 1-2 days per week), active, and sedentary males, 66 years of age. In low risk men (low risk of heart disease), sedentary men had a higher risk of death than weekend warriors and regularly active subjects. In high-risk men, weekend warriors had the same risk of death as sedentary men, but regularly active men had the same risk of death as active men with low risk. What does this mean? Some exercise is better than none, as long as you have few risk factors of heart disease. Regular exercise provides protection against sudden death, even in people with significant risk factors of heart disease.

Source: Am J Epidemiol. 160: 636-641, 2004.

What about healthy young athletes who die suddenly during exercise?

Although the sudden death of a young athlete (under age 35) tends to attract a lot of attention, it is an uncommon event, occurring in about 1 out of 200,000 athletes per year. The majority of these deaths are due to congenital cardiovascular conditions that are usually without prior symptoms and are therefore unlikely to be diagnosed during life without specific screening. These conditions also occur in the general population but may be more lethal during intense physical activity. Indeed, most young athletes who die suddenly do so during or immediately after training or competition.

          The most common cardiovascular cause of sudden death in young athletes is hypertrophic cardiomyopathy, which accounts for about one-third of cases. In this condition, the heart muscle becomes very thick, impeding the outflow of blood and causing fatal arrhythmias, especially during physical activity. Some people have a mild form of this condition; during screening tests, it may be difficult to distinguish such an afflicted heart from a normal athletic heart, which (like any other muscle) becomes bigger from physical activity.

          The second most common cardiovascular cause of sudden death in athletes is congenital coronary artery anomalies, which account for about 20% of cases. In this condition, a coronary artery is malformed or doesn't arise from its normal position on the aorta. During physical activity, the artery may be unable to provide adequate blood flow to the heart muscle, leading to damage to the heart cells or to fatal arrhythmia.

          Congenital malformations, including problems with the heart valves and the electrical conduction system, account for most other sudden deaths among athletes. Coronary artery disease is a more common cause in older athletes but rarely occurs in younger athletes. In about 2% of deaths, no cause can be identified. Some of these deaths maybe due to non-cardiac factors, including substance abuse or the use of dietary supplements that have been linked to cardiovascular problems.

Does exercise affect longevity?

The famous exercise physiology researcher Per-Olaf Åstrand once said that if you don't want to exercise, you should see a physician to determine if you can withstand the destructive effects of a sedentary lifestyle. Other people think that exercise doesn't make you live longer—it only seems longer. Which position is correct? Regular exercise can make you live 3 years longer, according to data from the famous Framingham study—a study of the lifestyles and causes of death of people living in Framingham, Massachusetts. At age 50, exercising moderately every day increased the lifespan 1.5 years above sedentary people, while exercising intensely lived 3.5 years longer. Also, active people were healthier than non-exercisers, meaning they had a higher quality of life. Exercise is vital to metabolic health. Regular exercise prevents cardiovascular disease and increases total life expectancy. The gains are even more impressive in people who exercise intensely. The old maxim that if you don't use it you lose it is certainly true when it comes to physical activity and aging.

Source: Arch Intern Med. 165:2355-2360, 2005.

Do I need to join a gym or buy exercise equipment in order to build fitness?

No. There are many ways to increase physical activity and boost physical fitness without spending money on a gym membership or equipment. Activities such as walking, stretching, and calisthenics can be practiced by anyone at no cost. Low-cost options include small hand weights, stability balls, and jump ropes. Exercising at home is convenient and private—characteristics that you may value. On the other hand, you may prefer to train at a gym because of the variety of exercise options and equipment and because it offers the opportunity to train with others. If you like the idea of training in a gym, look for inexpensive options. For example, your school or employer may offer free or low-cost gym memberships.