Physical Activity Levels in CF Should Be Objectively Researched, Review Says

Adults with cystic fibrosis (CF) are less active than they should be, although they have comparable activity levels to people without the genetic disorder, according to a recent review.

The review also showed that there are not enough studies that objectively assess physical activity levels in CF. Therefore, more research in this area is warranted, the investigators said.

The study, “Physical activity and associations with clinical outcome measures in adults with cystic fibrosis; a systematic review” was published in the Journal of Cystic Fibrosis.

Physical activity is known to benefit all people, but CF patients gain even more from being physically active because exercise can slow down the decline in lung function. It also can help clear mucus from the lungs, among other benefits.

Experts recommend at least 150 minutes of moderate-to-vigorous physical activity each week, and walking a minimum of 10,000 steps per day for all individuals. In CF patients, doctors don’t often assess their physical activity in a consistent way. Given that, very little is known about patients’ exercise habits.

Now, researchers at Liverpool John Moores University, in the U.K., sought to evaluate physical activity levels in CF adults. The goal was to compare their exercise habits with expert recommendations, and to those of people without the genetic disorder.

To do so, the investigators reviewed 18 studies. Scientific articles had to include measurement of physical activity and/or sedentary behavior using a tool validated for use in the general adult population and/or adults with CF, as well as quantification of baseline physical activity and/or sedentary behavior prior to any interventions.

In five out of eight studies in which such assessment was possible, adults with CF were found to not practice 150 minutes of moderate-to-vigorous physical activity each week, or walk 10,000 steps per day. Importantly, those without the disease also failed to meet expert recommendations, and did so approximately in the same proportion as CF patients.

In addition, scientists observed no differences between CF and healthy subjects’ physical activity levels in three out of five studies.

A total of 13 studies investigated the association between physical activity and other clinical outcome measures, including lung function, body mass index, exercise capacity, and exacerbation frequency. However, there was not enough evidence to backup a relationship between lung function, exercise capacity, and physical activity.

Only three studies used objective physical activity assessments, meaning participants used accelerometer-based systems to quantify their movement. In these studies, associations between physical activity and clinical variables were more evident, in comparison with studies that used self-reported physical activity.

Notably, the researchers said all of the studies analyzed were of low quality.

“There is a requirement for high quality studies designed specifically to explore PA [physical activity] in adults with CF, ideally employing standardised PA [physical activity] assessment methods,” the researchers said.

Overall, based on the results, the team concluded that physical activity “in adults with CF is largely comparable to their non-CF peers, despite being insufficiently active to achieve PA recommendations.”