Aerobic exercise has multiple benefits including:

• Lowering blood pressure
• Improving cholesterol
• Improves blood clotting
• Lowers risk for cardiovascular disease
• Reduces the risk of heart attack, stroke and peripheral vascular disease
• Improves mood
• Prevent and even treat anxiety and depression
• Improve sleep

Aerobic exercise - walking, biking, jogging, swimming and aerobic exercise classes - uses large muscle groups to increase heart and breathing rate and leads to increased endurance.

Strength training - which can be accomplished with free weights, machine weights or the body weight - offers different benefits than aerobic training. It increases muscle mass, enhances functional capacity, burns fat and strengthens bones. In 2006, only 19% of adults routinely participated in resistance training falling well short of the national goal of 30%

With the increasing prevalence of home video game systems, fewer children are active. It is important to encourage children to live active lifestyles so these habits become lifelong patterns. Risk of Exercise

While exercise is highly recommended, there is risk. High-risk individuals should discuss an exercise program with their health care provider. Most individuals who participate in moderate activity will be encouraged to exercise without limitations. Some higher risk patients who want to engage in vigorous exercise will require a complete medical evaluation including an exercise stress test.

Exercise prescription describes how one should exercise. Each mode of exercise - aerobic exercise, strength training and stretching - has a specific exercise prescription. Aerobic Exercise

Aerobic exercise prescription is broken down into frequency, intensity, duration and type.

Frequency: Aerobic exercise should be done three to seven times a week. When starting out, especially for the novice exerciser, it is a good idea to exercise three times a week with one day rest between exercise sessions. Increasing the frequency to 4 days a week is sensible in the beginning. Adding one day a week every few weeks assures the body adapts to exercise thereby minimizing soreness, injury risk or psychological burnout. Working up to some form of aerobic exercise or physical activity everyday is a good goal for all to have.

Intensity: Risks are minimized and benefits are maximized with moderate exercise. Vigorous exercise increases the risk of burn out, injury and non-compliance.

A simple method to gauge intensity is to use the talk test. Exercise hard enough to increase breathing rate, but, not working so hard that a conversation cannot be maintained without gasping for air.

The heart rate can be used to measure intensity, but this is a little more challenging for most people. Typically the maximal heart rate is determined and then the individual exercises at a percentage of the maximal heart rate.

The predicted maximal heart rate is calculated by subtracting the patient’s age from 220. For example, a 30 year-old would have a (theoretical) maximal heart rate of 220-30 or 190 beats a minutes.

There can be individual variation using this method – not every 30 year-old has a maximal heart rate of 190. Some exercise professionals use a maximal stress test to determine the true maximal heart rate. The exercise professional can use a variety of formulas to determine the optimal heart rate training zone based on the results of a maximal stress test. Individuals who want to utilize the heart rate method to determine exercise intensity should use a heart rate monitor strap or use the services of trained exercise professionals.

Duration: When starting an exercise program, the novice exerciser, should keep the duration minimal. The exerciser should gradually increase the duration of exercise. Patients may start out 10-20 minutes a day and add 1-3 minutes per exercise session until they are exercising for a minimum of 30 minutes per session. Aerobic exercise should be carried out for a maximum of 60 minutes per day.

Type: Exercise should involve the large muscle groups such as the legs, performing exercises like walking, biking, exercise classes and swimming. Exercises that are enjoyed are complied with better, therefore, it is important to consider personal preference when selecting an exercise.

Exercisers can employ cross training which reduces boredom and may reduce injury risk. Cross training involves either performing a different mode of exercise during each exercise session or doing different modes of exercises within one training session. Cross training could include:

• Monday: walk on the treadmill for 20 minutes, Wednesday: a water aerobic class, and Friday: riding the stationary bike for 30 minutes.

• Ten minutes on the stationary bike, ten minutes on the elliptical trainer and 15 minutes walking on the track during one session.

  Strength Training

Strength training increases muscle strength and mass. It also enhances the ability to function in day-to-day life and reduces the risk of certain diseases.

While many body builders lift weights every day of the week, for health benefits strength training should be done 2-3 times a week with at least 48 hours rest between sessions. Muscles need time to recover after a weight training session. When the same muscle group is stressed within 48 hours of the previous session the muscles will not adapt ideally and may be overworked. Each weight training session typically takes between 15-45 minutes and includes at least one exercise for each major muscle group of the body (table 2).

Intensity is difficult to conceptualize in regard to weight training. There is no specific formula or weight to tell a person what to lift – it often requires a lot of trial and error. Each muscle group and each exercise will require a different weight and a general rule should include picking a conservative weight. The eventual goal is to select a weight that offers enough resistance so the last repetition in a set is the last repetition that can be done without compromising form.

Progressive overload should be incorporated into an exercise training session. Progressive overload involves increasing the amount of work – either with weight, repetitions or sets – on subsequent exercise sessions. Progressive overload obliges the muscle to gain strength. Remember, safety first, never compromise form to overload, if the body cannot do more work – do not force it.

For health benefits it is best to choose a weight that allows 8-15 repetitions to be performed. This is the correct range for improving strength and endurance. Power athletes will select higher weights and do fewer repetitions. This will improve strength, but it does increase the risk of injury.

One to two exercises for every major muscle group is recommended. Select an exercise for each muscle group using table 2. Bigger muscle groups may have 2 different exercises. As strength and endurance improves, increase the number of sets to 3 for each muscle group. This will result in more benefit in relation to strength and endurance, but will add more time to the routine and increase the risk of psychological burn out or injury. Start off being conservative with weights, sets and repetitions and gradually increase.