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Overview of Exercise


Brian D. Johnston

, Exercise Specialist, International Association of Resistance Training

Reviewed/Revised Aug 2023

There are many benefits of exercise Benefits of Exercise Regular exercise makes the heart stronger and the lungs fitter, enabling the cardiovascular system to deliver more oxygen to the body with every heartbeat and the pulmonary system to increase... read more . Exercise is one of the most effective and, when done properly, safest ways to enhance health and wellness. For example, exercise can strengthen the cardiovascular system, lower blood pressure, improve the levels of fats, cholesterol, and sugar in the blood, strengthen muscles, prevent falls, and improve mood. As a result, people may function better, live longer, and avoid many common disorders. Benefits of exercise usually far exceed the possible harms.

Still, harms are possible. Too much weight-bearing or resistance exercise can contribute to joint wear and tear, increasing the risk and severity of osteoarthritis. Also, people with certain disorders must restrict their activity. For example, people with coronary artery disease must restrict the intensity of their aerobic exercise.

Aspects of any exercise program include its

  • Frequency (how often)

  • Intensity (how hard)

  • Time (how long)

  • Type

The general principle behind all types of exercise is that your body responds to increased physical demands by becoming more capable (stronger, faster, more efficient). Different types of exercise place demands on different components of your body.

General categories of exercise include the following:

Exercise Programs

Each type of exercise has different goals and benefits as well as the kinds of equipment and facilities that are required. For beginners, it can be hard to know where to start when designing an exercise program. Whatever exercise is chosen, it is important to learn to do the exercises properly to maximize benefit and minimize risk of injury. Local fitness centers can be a good resource for information regarding safe and effective training. Fitness centers usually also offer exercise classes and/or personal trainers that can introduce people to different types of exercise. Many people find that taking an exercise class helps keep them motivated to continue and minimizes the need to come up with their own program. However, even if fitness centers are unavailable or unaffordable, there are many ways people can exercise effectively with minimal equipment.

Exercise has similar benefits whether done alone (self-directed or using an instructional video), in a group (in person or virtually), or with a personal trainer. Preferences vary from one person to another, but the most beneficial method of exercise is one that an individual will do consistently. Just as with dieting, the theoretically best exercise program is of no use if people cannot stick with it, and a merely adequate exercise program that people enjoy and will do regularly will provide good long-term benefit.

Consider the idea of "diminishing returns" when thinking about the amount of exercise required (as opposed to "tolerated") to achieve a particular outcome or goal. A small amount of exercise may yield some results, but perhaps not the full or intended results. More activity would be required to generate desired results, but at some point the harm outweighs the benefit. For example, 25% more work may yield 5% better results but place more strain on the person's joints and mental and physical capabilities, and the additional work may require more recovery time. Therefore, structure an exercise program to increase the overall demands (for example, how much or how hard to exercise) only gradually.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

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