Exercise Testing and Training for Individuals with Cystic Fibrosis

Abstract

Cystic fibrosis (CF) is a progressive genetic disease that impacts multiple systems (e.g., respiratory system). Hence, routine cardiopulmonary exercise testing (CPET) is recommended to track the disease progression in people with CF. Besides the benefits of exercise testing, exercise training is also beneficial for long-term wellness. It is recommended that people with CF engage in at least 30–60 minutes of aerobic exercise 3 days a week. However, despite the significance of exercise testing and training for people with CF, CPET and exercise training are underutilized in international CF centers. According to the literature, the majority of international CF centers use field-based exercise tests, such as the 1-minute sit-to-stand test (STS), to assess muscle strength and functional status. The 1-minute STS test is one of the exercise tests suggested for people with CF, as the test is cheap and can be conducted in a limited time and space. To our knowledge, there is a gap in the literature regarding use of a validated survey to assess the utilization of exercise testing and training in U.S. CF centers. Additionally, the incorporation of verbal encouragement into the 1-minute STS protocol has not been investigated, which could be used to enhance exercise performance, as the test is self-paced and may underestimate actual physical performance. iii Therefore, we aimed to establish the content validity of an exercise testing and training survey and use it to capture the use of exercise testing and training programs in U.S. CF centers. We also aimed to test whether the encouraged 1-minute STS test can provoke higher exercise intensity as compared to the standard 1-minute STS test. Overall, the feedback we received in the Delphi study improved the overall quality and content validity of the survey. In addition, the results of the validated survey showed that CPET is underutilized in U.S. CF centers, unlike field-based exercise tests. Moreover, the encouraged 1-minute STS test resulted in higher exercise performance as compared to the standard 1-minute STS test; therefore, the encouraged 1-minute STS test appears to be a promising alternative for regular exercise testing in clinical settings for people with CF, as the test is time-and space-efficient, especially when CPET is not available.