Staying Healthy Show
Image: © ninikas/Thinkstock Are you working hard during exercise — or hardly working? Guidelines recommend at least 150 minutes of moderate-intensity exercise per week. But "moderate intensity" can vary per person. What is an effort to one person can be easy to another. A good way to maintain your level of moderate intensity is with heart rate training, where you exercise at 60% to 75% of your maximum heart rate. This is your cardio Goldilocks zone where the intensity is not too hard or too light, but just right. "Heart rate training can give you an ongoing reminder of your intensity and tell you when you need to pick up the pace or slow down," says Dr. Aaron Baggish, director of the Cardiovascular Performance Program at Harvard-affiliated Massachusetts General Hospital. "This way you can stay within your moderate-intensity zone as much as possible." Getting into the zoneWhat is your moderate-intensity zone? First, you need to know your maximum heart rate — the upper limit of what your cardiovascular system can handle during physical activity — as measured in number of heartbeats per minute. One way to find your maximum heart rate is with a stress test, in which you walk or jog on a treadmill that makes you, and thus your heart, work progressively harder while an electrocardiograph monitors your heart's electrical rhythms. While this is the most accurate way to determine your maximum heart rate, a simpler option is to use a formula based on your age, which can offer a good estimate. Dr. Baggish suggests 200 minus half your age. Once you know your maximum, you can figure your target zone as 60% to 75% of that number. For example, a 70-year-old man would have a maximum heart rate of 165 beats per minute. Therefore, his moderate-intensity heart rate zone would range from 99 to 124 beats per minute. Heart rate workoutsAfter you determine your target heart rate zone, your workouts should break down like this, according to Dr. Baggish:
It's also a good idea to stay in the low end (60%) of your target zone for a few weeks and build up to 75%. "Also, remember that if you're not able to carry on a conversation at any time while exercising, the intensity may be too much, no matter what your optimal heart rate zone," says Dr. Baggish. If you have difficulty staying in your zone for 30 minutes, do intervals: Slow your pace for a few minutes, and then increase the intensity until you reach your target heart rate zone again. Stay there for one to two minutes or longer, and then slow down again. Repeat the back-and-forth cycle for 30 minutes. "As your conditioning improves, you will be able to stay longer in your heart rate zone until eventually you can do the entire 30 minutes," says Dr. Baggish. Heart rate training is not for everyone. Talk with your doctor to determine if it is right for you.
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Although many people view exercise as a way to lose weight, it plays a key role in the wellbeing of the body beyond weight loss. Research strongly supports its benefits across a range of physical and mental health conditions for people of all ages. However, busy lifestyles and an environment that encourages being sedentary for many hours of the day (driving door-to-door, sitting at an office desk, relaxing for the evening in front of a television) have led to exercise ranking low as a priority for many people. Types of ExerciseAll types of exercises offer health benefits. Performing different types of exercises can expand the range of benefits even further. But it is important to remember that some exercise is better than none, and that most everyone can participate in some form of exercise safely. Aerobic/Cardiovascular physical activity. These are activities that are intense enough and performed long enough to maintain or improve one’s heart and lung fitness. Examples: walking, jogging, dancing, bicycling, basketball, soccer, swimming Muscle-strengthening activity. This may be referred to as resistance training. These activities maintain or increase muscle strength, endurance, and power. Examples: weight machines, free weights, resistance elastic bands, Pilates, daily activities of living (lifting children, carrying groceries or laundry, climbing stairs) Flexibility training. This may be referred to as stretching. It lengthens or flexes a skeletal muscle to the point of tension, and holds for several seconds to increase elasticity and range of motion around a joint. Improving flexibility can enhance the overall physical performance of other types of exercise. Examples: dynamic stretches performed with movement (yoga, tai chi), static stretches without movement (holding a pose for several seconds or longer), passive stretching (using an external force like a strap or wall to hold an elongated pose), and active stretching (holding a pose without an external force) Balance training. These activities are intended to throw off one’s balance to improve body control and stability. They can help to prevent falls and other injuries. Examples: standing on one foot, walking heel-to-toe in a perfectly straight line, standing on a balance or wobble board Measures of Exercise IntensityAlthough just moving more and sitting less offers health benefits, how much energy you use while exercising can increase those health benefits further. This is referred to as energy intensity. Borg ScaleThe Borg Scale of Perceived Exertion measures your exercise intensity by rating how you feel. It is based on observations like higher heart rate, heavier and faster breathing, increased sweating, and muscles feeling tired. It does not use actual measurements of these occurrences but a personal self-check. The scale uses numbers from 6 to 20. The lowest rating is “no feeling of exertion,” at number 6, and the highest rating is “very, very hard,” at number 20. Moderate activities register 11 to 14 (“fairly light” to “somewhat hard”) while vigorous activities usually rate 15 or higher (“hard” to “very, very hard”). Dr. Gunnar Borg, who created the scale, set it to run from 6 to 20 as a simple way to estimate heart rate—multiplying the Borg score by 10 gives an approximate heart rate for a particular level of activity. [1] The Borg Scale of Perceived Exertion
Exercise workouts may vary in intensity throughout the session. You can use the Borg Scale to change the intensity, by speeding up or slowing down movements or applying more or less resistance (such as increasing the incline on a treadmill or turning the resistance control knob on a stationary bicycle). Target Heart RateCalculating your heart rate and target heart rate can be used to measure exercise intensity. First determine your maximum heart rate: subtract your age from 220 (example: the maximum heart rate for a 40-year-old person would be 220 – 40 = 180 beats per minute). The target heart rate for moderate-intensity exercise is between 65-75% of your maximum heart rate (or 77-93% of maximum heart rate for vigorous exercise). So for the 40-year-old person with a maximum heart rate of 180, the target heart rate falls somewhere between 117-135 beats per minute for moderate exercise, or 139-167 for vigorous exercise. Then measure your actual heart rate in either of these two ways:
METsMET stands for the metabolic equivalent of task. One MET is the amount of energy used while sitting quietly. Physical activities may be rated using METs to indicate their intensity. For example, reading may use about 1.3 METs while running may use 8-9 METs. METs can also be translated into light, moderate, and vigorous intensities of exercise.
More on METs
Moderate-intensity activities are those that get you moving fast enough or strenuously enough to burn off three to six times as much energy per minute as you do when you are sitting quietly, or exercises that clock in at 3 to 6 METs. Vigorous-intensity activities burn more than 6 METs. One limitation to this way of measuring exercise intensity is that it does not consider the fact that some people have a higher level of fitness than others. Thus, walking at 3 to 4 miles-per-hour is considered to require 4 METs and to be a moderate-intensity activity, regardless of who is doing the activity—a young marathon runner or a 90-year-old grandmother. As you might imagine, a brisk walk would likely be an easy activity for the marathon runner, but a very hard activity for the grandmother. This table gives examples of light-, moderate-, and vigorous-intensity activity for healthy adults:
Physical Activity Through the Life CourseIn the U.S., the Department of Health and Human Services provides specific guidelines for physical activity for different life stages and conditions: [2]
The frequency, duration, and intensity of exercise are helpful terms to consider when deciding on an exercise regimen.
If you are health-conscious, chances are you like seeing data that reveals information on how you are doing. Pedometers, heart rate monitors, and sleep trackers can all analyze what goes on inside our bodies. Most of these devices are combined with a smartphone or computer app that provide tracking tools to better manage personal health, and can be an effective source of motivational support. [3] The data may be shared with one’s physician or other health care provider to monitor progress with physical activity goals. Trackers can motivate people to change behavior, whether this means getting up and moving more, going to bed earlier, or advancing an exercise routine to challenge the heart. [4] But how reliable are they? Generally these trackers are pretty accurate when measuring steps taken. But other measures, such as how many calories are burned, can overestimate or underestimate the actual amount. Studies looking at the accuracy of devices in tracking calories used while exercising tend to be small in size. In one study, 14 participants wearing different popular brand devices walked and ran. The estimated calorie usage displayed on the devices was compared with measurements from indirect calorimetry (a reliably accurate technique to measure calorie output). The results were mixed. Some of the devices were accurate for calorie expenditure with running but not walking and visa versa. Some of the devices overestimated the amount of calories used during exercise. [5] Other studies found similar discrepancies. [6] Tracking devices can be useful for personal motivation and accountability, but the data should be interpreted with caution as there are variable readings among devices. The accuracy of the data may also vary within the same device when performing different intensities of exercise. [6] They are best used with other methods to gauge fitness levels, such as monitoring the frequency, duration, and perceived exertion of your exercise routine. It’s also important to have motivation to exercise because you enjoy how you feel during and after the exercise, not just to reach a certain number on a tracker. Exercise SafetySafety should be a major priority when exercising. Any physical activity carries the risk of injury, whether you are just starting an exercise regimen or are a seasoned fitness buff. But don’t let this stop you from moving because the health benefits of being active far outweigh any risks. Using caution and patience can reduce the risk of injuries. Common workout injuries include:
In very rare cases, vigorous physical activity may lead to a heart attack or sudden death. Active people have a lower risk of serious or fatal heart problems than inactive people. Common missteps: Not talking with your doctor first. If you are new to exercise or have medical conditions, let your doctor know what type of exercise you’ll be starting. They can review the format to ensure it is safe with a specific health condition. Doing too much too soon. This is very common as people may be highly motivated when starting a new exercise program. However, forcing your body to move with too much intensity can be jarring to the heart, muscles, and joints that may lack strength from inactivity. This often leads to injury. Even if starting slowly feels too easy, plan to progress exercise gradually. Start with light to moderate-intensity movements for a shorter amount of time, and continue this for a few weeks. As you develop strength and stamina, you can add minutes and higher-intensity movements every few weeks. Leaving out the warm-up and cool-down. A warm-up before exercising includes light movements that initiate the flow of blood and loosening of muscles and joints. An example would be 5-10 minutes of marching in place, doing arm circles, and neck rolls. After exercising, the cool-down is important to slow down the body and heart rate steadily, as a sudden stop in movements can interfere with blood flow to the brain and cause lightheadedness or dizziness. A cool-down could be simply slowing the pace of whatever exercise being performed for 10 minutes (if jogging, change to a walk; if on a stationary bicycle, release any tension on the resistance knob and peddle slower). The cool-down period may also include stretches that are most effective when the muscles are warmed from exercising; stretches help to lengthen muscles that will protect against injuries. A cool-down with stretching can also lessen muscle soreness the following day. How to get started safely
10 Tips to Keep Moving
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