Training

FITNESS TRAINING GUIDELINES

Once a decision has been made to train for cardiovascular fitness, and once a qualified health advisor has determined that it is medically prudent and safe for an individual to undertake such an endeavor, certain guidelines are useful for determining the type and amount of exercise required. Many doctors will provide an exercise "prescription" for each patient, and this should always take precedence over any general guidelines such as these.

The three major factors in judging the "quality" of a training method are its duration, intensity, and how often it is done. In addition, the mechanical aspects of the activity must be considered from a safety standpoint.

Intensity

In order to promote cardiac fitness, an exercise must "stress" the heart and circulation sufficiently to achieve the training effect. Just as lifting a pencil will not build up bulky arm muscles no matter how often it is done, neither will a leisurely stroll build fitness.

Authorities are not sur exactly what level of intensity is universally best, but most agree that optimal training should be vigorous enough to raise the pulse to at least 75% of the predicted maximum for your age. Lower intensities may be suitable for many, as noted below, but this goal is appropriate for many dedicated individuals who are interested in improving performance as well as fitness. The maximum heart rate is approximated by subtracting one's age from 220. Thus, a 40 year old would strive for 75% of [220-40], i.e. 135 beats per minute. As one's fitness increases, a given amount of exercise raises the pulse less and less, and this is one mark of a successful program.

Another approach is to choose an intensity equal to 5 or 6 METs. METs are a measure of oxygen consumption, and the various METs of selected activities are listed in another section of this area of HealthNet. As an example, even moderately brisk walking and cycling achieve this level of intensity.

Finally, the more casual candidate can simply perform to the point where she is aware of "working hard" but still able to speak fairly comfortably, and without excessive breathlessness. One point is clear: intensity must be sufficient for a sense of physical exertion to occur, though this need not, and sometimes should not, be severe.

Duration

Depending upon the intensity of exercise chosen, the activity should be performed for at least 20 minutes at a time, and continuously during that period. Longer sessions up to an hour are naturally more effective. Many choose to alternate a slightly more intensive 20 to 30 minute work-out with a longer but less vigorous session the next time. There is considerable flexibility here, as long as a 20 minute minimum is maintained.

Stop-and-go activities are surprisingly inefficient, even if prolonged and fatiguing. Thus, a 3 hour doubles tennis match where actual motion occurs irregularly and intermittently is not a very effective training activity when compared to 20 minutes of jogging, handball, swimming or other similar activity. The social value and sense of muscular fatigue may have recreational merit, but no praise is earned for fitness.

Frequency

It is advisable to work out at least three times a week. Lesser frequencies allow for some deconditioning between sessions, and are much less effective overall. Many competitive athletes will train 6 or 7 days a week, and although their conditioning is accelerated, it is recognized that the incidence of musculoskeletal injuries increases markedly as frequency increases above 3 times weekly.

There is some practical and theoretic advantage to skipping a day between sessions. Minor injuries and inflammation of ligaments, tendons, muscles and other tissues have a chance to subside, and injuries are less frequent. The psychologic burden of discipline is reduced, and this enhances the likelihood of sticking with the program. In this hurried world, the total time spent in exercise can sometimes cause conflicts, and an alternate day regimen allows for some flexibility of scheduling.

Warm-Up and Cool Down

A few minutes spent in slowly stretching the muscles to be used can reduce the chances of "sprains, strains, and pains." Sustained stretches are preferable to "bouncing" types of calisthenics. A brief session of deep breathing will expand the lungs and stretch the muscles of respiration.

Even more important than the above is a period at the end of the work-out in which the intensity of activity is allowed to gradually decrease--a "cool down." Either by simply slowing down or repeating the simple warm-up types of exercise, a sudden cessation is avoided. This is crucial since during exercise, high levels of adrenalin can build up in the blood. This is rapidly consumed during vigorous activity, but when the activity stops, these chemicals may accumulate for a few minutes. In a few sensitive individuals, such accumulations may be dangerous to the heart. The cool down allows for the controlled metabolism of the substances while their production is decreased, thereby sparing the heart from such exposure.

Fluid and Food

Circulation to the digestive organs diminishes during exercise, and food in the stomach is likely to cause discomfort. Thus, training should occur at least 90 minutes after the last meal or snack. Fluid in the form of water seems to cause little trouble despite anecdotes to the contrary, and especially in warm conditions or during sustained exercise, ample water should be consumed both before and during exercise.

Dehydration can occur rapidly through perspiration, and thirst (or its absence) has been shown to be a poor guide to the level of hydration during exercise. Damage to kidneys, low blood pressure, and chemical imbalances can occur from too little fluid, and most authorities advise athletes to drink often. There is no advantage to fluids other than water in this context.

The Novice

It may seem obvious, but the guidelines in the above discussion are for the conditioned person, and the newcomer to exercise may require 6 weeks or more just to achieve the minimal fitness conditions outlined. Since fitness is a lifelong habit, this is not really a long time, but some will be eager to rush things along. It is NEVER safe to extend one's activity to the point of non-trivial pain or lightheadedness, or severe fatigue. Of course, unexplained pain in the chest, neck, arm, abdomen, jaw, or back demands urgent medical attention. Any athlete who appears to be confused or disoriented during exercise should likewise be brought to medical attention. Common sense and caution are imperative.

Within these guidelines, almost any individual can enjoy lifelong fitness, an improved sense of well-being, and the many other advantages of fitness discussed elsewhere. It is safer to exercise regularly than to avoid fitness altogether, and the risks of exercise itself can be minimized through adequate medical screening, sensible guidelines, and attention to the signals of the body.