For details regarding exercise testing equipment and exercise testing laboratories, the reader should refer to the AHA’s “Guidelines for Clinical Exercise Testing Laboratories.” illustrates the relation of METs to stages in the various testing protocols. The treadmill and cycle ergometer are now the most commonly used dynamic exercise testing devices.
Maximal work capacity in normal individuals is influenced by familiarization with the exercise test equipment, level of training, and environmental conditions at the time of testing. In estimating exercise capacity, the amount of work performed in METs (or exercise stage achieved) should be the index measured and not the number of minutes of exercise. Serial comparison of exercise capacity in individual patients to assess significant interval change requires a careful examination of the exercise protocol used during both tests, cardioactive drug therapy and time of ingestion, systemic blood pressure, and other conditions that might influence test performance. Each of these factors must be considered before attributing changes in functional capacity to progression of coronary heart disease or worsening of LV function.
Numerous noncardiac conditions that frequently occur in older adults may limit their ability to undergo aerobic exercise testing. Some disorders, such as peripheral arterial disease and chronic obstructive lung disease, frequently coexist with CAD due to shared risk factors. Degenerative arthritis of weight-bearing joints is the most prevalent chronic disorder in older adults. Finally, the unfamiliarity with vigorous exercise and exercise testing equipment may intimidate elderly patients, causing them to perform submaximally.