The FITT Principle
What, when, and how much to exercise?

Think of the FITT principle when choosing and starting an exercise. regimen. It's a guide to help you decide how often, how intense, how long, and how to choose a specific exercise . It is an easy way to remember the key components of exercise prescription for people over 50.

F = frequency - how often to exercise
I = intensity - how hard to exercise
T = time - how long to exercise
T = type - how to choose an exercise

F is for Frequency

The experts such as the American Council of Sports Medicine ACSM recommend for the 50+ population cardiovascular endurance exercise (such as: walking, jogging , swimming and linkWALKAEROBICS) done at a frequency of 3 to 6 days a week. Beginners should start with 3 times a week, skipping at least a day in between. This is generally agreed upon by experts, but our linkWalkaerobics study has shown that even less exercise will be effective for a deconditioned, "couch potato." Even if you start out exercising only twice a week, you can reap benefits. In fact, exercising too much can cause more problems than too little, due to problems of fatigue and the increased chances of an overuse injury. As you get adapted to the exercise you can add additional days, if you wish. But don't overdo it. Rest one whole day for every three or four days of exercise. Once injured, we don't return to exercise for a long time, if ever.

I is for Intensity
Exercise specialists assess the intensity of an activity or exercise by linkchecking our heart rate/pulse while we do that activity. We count how many times our heart beats per minute at rest and again during or after we exercise. We compare our heart rate with the normal heart rate for the general population (the population "norm"). These norms are presented as percentages.

T is for Time
The time or duration of the aerobic portion of the exercise session should be between 12 minutes and 60 minutes.The less fit you are, the shorter the duration and the more often you should exercise. As you become leaner and fitter, you will need to exercise for a longer duration, more intensely, and less often.
When you start your exercise program you may decide to walk around your local high school track. You might be able to do it for only 5 minutes before feeling tired. You might find walking takes a tremendous effort and you can't go very fast. Your heart rate may reach your 60% or may not. Your extra fat may hamper you from walking fast to raise your heart rate very much. On the other hand, if you have a strong, healthy heart, your legs, feet, ankles, or lungs , may tire before your heart has to work at all. Your heart may only get up to its 40% or 50%, but you are still burning calories (one mile consumes approximately 300 kcals).

Or the opposite might happen. Your extra fat pounds and couch potato life-style may make walking even a short distance stress your cardiovascular system and heart, raising your heart rate higher than 60%, and possibly as high as 70% or 80%.

In both cases you should try to achieve a comfortable, moderate pace and if you return to the track 3 to 5 times a week, you will find that in a period of time you can walk longer and more briskly. When you can walk for 30 minutes without stopping and you can sustain a heart rate of 50% to 60%, then 3 times per week is enough.

T is for Type
Any exercise induced net calorie deficit can result in fat loss. Weight lifting, however, may lead to a gain in lean body weight and therefore can cause a discouraging gain in overall weight. But the benefits it offers in strength and body image make it worthwhile. Whereas a low impact aerobic exercise, such as walking and Walkaerobics, usually results in a maintenance of lean body weight, strengthens the entire cardio/repiratory system, builds overall body strength,. Both types plus stretching are recommended in well rounded health and fitness regimen.

The Most Effective Aerobic Activities are:
brisk walking (outdoors or indoors)
treadmill walking
Walkaerobics
stationary biking (caution: knees)
stair climbing (caution: knees)
jogging (caution: impact injuries)
low impact aerobics (caution: joint injuries)