Your heart is a little like a machine that gets dialed to low, medium or high depending on the intensity of the exercise you're doing. However, machines aren't human, so if you've been leading a sedentary lifestyle a low-intensity workout can still dial your heart to high. Activity levels are often determined by how hard your heart works when you exercise. They also describe the types of activities and exercises you typically perform in a week and your overall fitness level.
A sedentary activity level describes someone who gets little to no exercise. If you spend a lot of time sitting at a desk or watching television, without working out regularly, you’re considered sedentary. The activity you do perform during your daily routine is low-intensity. When you exercise at a low-intensity level, you are able to breathe normally, and are able to sing while you perform an activity. Under normal conditions, low-intensity exercise will not make you sweat. Examples might include taking an easy walk, stretching, shopping and light gardening. At this level, health care professionals will likely recommend that you start a regular exercise regimen to strengthen your heart and improve overall health.
If you do exercise but get less than the 2 1/2 hours per week of the moderate aerobic activity that the Centers for Disease Control and Prevention recommends, you’re at a moderate activity level. With aerobic exercise at a moderate intensity level, you breathe harder and deeper than at a sedentary level. You can't sing any tunes, but you can hold a conversation as you take a brisk walk, which is a good example of a moderate level exercise. After around 10 minutes of exercise, you should break into a sweat. Mowing your lawn, riding a bike on level surfaces and playing doubles tennis are examples of moderate exercises.
If you work out vigorously for at least one hour and 15 minutes every week, you’re at a high activity level. At a vigorous level of exercise your heart is working at maximum efficiency. Talking will be difficult at this level and you will breathe rapidly. You will break into a sweat after just a few minutes doing exercises like biking or hiking on hills, jogging, swimming laps, playing basketball or high-intensity aerobics.
It’s helpful to know your maximum heart rate to monitor your progress during exercise. Subtract your age from 220 to determine your maximum heart rate. Your target heart rate will fall between 40 to 85 percent of the maximum heart rate when you are exercising. If you're sedentary, aim at the lowest point of your target heart rate. After a few weeks you may be able to increase your exercise level to moderate, working your way up to the high end of your target heart rate. If vigorous activity is too much for you, you can gain the most benefit by exercising moderately for five hours per week.