Exercise as it relates to Disease/Correlation amongst physical activity and lung health in patients with cystic fibrosis

This is a critique of the research article by Jane Scheneiderman, supervised by Felix Ratjen: Longitudinal Relationship between Physical Activity and Lung Health in Patients with Cystic Fibrosis (CF), from the educational research journal.[1] This critical elaboration was written as an assignment for the University of Canberra, unit Health Disease and Exercise.

What is the Background to this researchEdit

Cystic fibrosis is a chronic, life limiting, incurable lung disease, which causes severe health consequences to respiratory and digestive tracts.[2] This disease is caused by mutation in CF transmembrane conductance regulator, with caucasians being the most genetically predisposed.[2] Disruptions to cardiorespiratory function by CF limits daily physical activity. Furthermore, the suppressed immune system often limits the patient to staying in carefully monitored indoor environments

Habitual physical activity (HPA) is of importance for reduction of CF severity amongst the young population.[1] HPA is considered as any physical activity which limits sedentary periods, and improves overall health. Such as walking, free play periods, any activity of the lower intensity and it’s less structured than training programs, furthermore HPA will improve overall health, strength, and aerobic capacity of the patients. Primary focus on aerobic training will enhance the cardiovascular system, resulting in increased lung capacity, better Iron absorption and enhancement of the mucus clearance.[1] Consistency in aerobic fitness development will diminish further progression of the chronic disease throughout the lifespan. This research is conducted on a mixed gender group, aged 7–17 and obtained baseline FEV1, Habitual Activity Estimation Scale and stage 1 aerobic cycle ergometer test scores in this group. This provides information on changes in lung capacity and physical activity participation changes following exercise intervention over nine years.[1]

Where is the Research fromEdit

The author of this study is Jane Schneiderman, Exercise Physiologist/Registered Kinesiologist at the Hospital for Sick Children in Toronto. Jane is an assistant professor in the department of Kinesiology and Physical Education at the University of Toronto. Her career in the Exercise Medicine Lab at the Clinical Research Centre is to research the effect of physical activity interventions on cystic fibrosis pathophysiology. She works to correlate Exercise Medicine into the diagnosis and treatment of the patients. Jane’s supervisor for this research was Flix Ratjen, division chief of paediatric respiratory medicine at the Hospital for Sick Children, professor of paediatrics at the University of Toronto, and Senior Scientist at the Research institute in the Translational Medicine research program. Felix Ratjen is co-leading the CF centre at Sick Kids and Medical Director of the Clinical Research Unit.[1]

What kind of research was thisEdit

This study is based on a randomised controlled trial, 212 patients were monitored over 9 years. They would randomly participate in physical activities of varying intensities, with no structured grouping being presented by the author. This questions the validity of the study, as it is not known what intensities of activity have the best outcomes. It is also not known if some participated in more activity than others. There is also no control group, meaning it cannot be determined if outcomes were due to the interventions or factors of the hospital. Moreover, it is not stated what happened to participants who would have become adults during the study, and whether they were included in the results or not.

What did the research involveEdit

212 patients with cystic fibrosis aged 7–17 years old from the two hospitals, the Hospital for Sick Children and Montreal Children’s Hospital.[1] Interventions were based on the regular stimulation of the cardiovascular system through any sort of physical exercising. Patients with current additional acute medical conditions, such as increased cough and sputum production, malaise, fever and/or physical participation inability, were not included in the research until they were eligible.[1] Based on this research, the decision to exclude any of the other acute or chronic diseases except CF will provide more accurate results. The results of this study may not be reliable as there was no control group meaning it can not be known if results were caused by the intervention or other factors in the hospital.

Methods of studyEdit

In the period of nine years, data collection was undertaken quarterly on the 212 study patients. The rule of exclusion of all patients with an acute disease was practiced, which led into the variable result outcomes. Radical measures of excluding patients should be criticised as all patients with CF are more susceptible to disease, therefore it should be considered in studies. Anthropometric measures were assessed, monitoring changes in body mass index, weight and eventually height. Pulmonary function testing using spirometry, however, specificity of the assessments were not outlined, therefore it is unknown if the procedures were consistent. Furthermore, dates of assessments were not outlined in this research.

Habitual Activity Estimation Scale was monitored at each quartile, on a typical weekday after the two week periods.[1] Total activity was monitored, data was collected from one weekday, on every second week. It is unknown how much activity they were achieving relative to the recommended guidelines of 30 to 60 minutes of daily moderate to vigorous physical activity.[3] Aerobic cycle ergometer test stage 1 was also conducted annually to determine peak oxygen consumption.[1] Overall results were recorded, but specific results for different ages, or individuals were not given.

What were the basic resultsEdit

The outcome of this study would indicate that any physical activity has a positive influence on the patient’s cardiovascular health. Thus, CF patients who are engaged in the physical activity would experience less respiratory function decline over the lifespan, compared to non active patients. This study indicates that aerobic activity interventions of any intensity would result with reduction of the disease’s progress. However, the methodology of the study means it is not known which frequency, intensity, time and type of exercise is optimal for the participants. All that can be taken is simply that some sort of physical activity has positive outcomes.

What conclusions can we take from this researchEdit

Increased physical activity/reduced sedentary time has profound health benefits on sufferers of cystic fibrosis. In this study, detailed specificities of the training programs were not presented, limiting specific information on intensities/duration of exercise. Research should be constructed more precisely to determine the optimal type, intensity and duration of exercise for individuals with cystic fibrosis.

Practical adviceEdit

CF requires an incorporated treatment approach in the specialised CF clinics, and a huge scope of non-medical and pharmaceutical therapies are required for the optimal patient’s outcomes.[2] Increased regular aerobic activities would diminish the disease progression through the lifespan, further study needs to be done for more constructed training interventions.

Further information/resourcesEdit

https://pubmed.ncbi.nlm.nih.gov/31226098/ https://pubmed.ncbi.nlm.nih.gov/15463875/


  1. a b c d e f g h i Jane S, Felix R. Longitudinal Relationship between Physical Activity and Lung Health in Patients with Cystic Fibrosis. European Respiratory Journal. [internet]. 2013 October [cited 2020 Sep 11] Available from: https://www.researchgate.net/publication/258214023_Longitudinal_Relationship_between_Physical_Activity_and_Lung_Health_in_Patients_with_Cystic_Fibrosis
  2. a b c Klimova B, Kuca K, Novotny M, Maresova P. Cystic Fibrosis Revisited - a Review Study. Med Chem. [internet]. 2017 [cited 2020 Sep 11]; 13(2):102-109. Available from: https://pubmed.ncbi.nlm.nih.gov/27292156/
  3. Sawyer A, Cavalheri V, Jenkins S, et al. Effects of high intensity interval training on exercise capacity in people with cystic fibrosis: study protocol for a randomised controlled trial. BMC Sports Sci Med Rehabil. [internet]. 2018 Nov 6 [cited 2020 Sep 11]; Available from: https://pubmed.ncbi.nlm.nih.gov/30450213/