Exercise as it relates to Disease/Cystic Fibrosis: Physical exercise versus chest physiotherapy
This is a critique of the original research article “Cystic fibrosis: physical exercise versus chest physiotherapy” M. Zach et al (1982) 
What is the background to this research?
Primarily affecting the lungs, airways and digestive system, Cystic fibrosis is a hereditary disease in which individuals produce an abnormal amount of excessively thick and sticky mucus.  The result of thick sticky mucus is due to the mutation in a gene which changes a protein that regulates the movement of salt in and out of the cell. 
Aerosol inhalation followed by chest physiotherapy is an essential part of the life-long therapeutic routine in CF patients. 
Chest Physiotherapy is the traditional airway clearance technique and involves the removal of thick sticky secretions to prevent infections and help ease breathing through postural drainage and percussion and vibration. 
Often with poor patient compliance, the efficacy of procedures to mobilise and remove secretions seems to decrease with age.  Hence, a more effective alternate is needed. The study conducted by M. Zach et al, observed whether exercise was more beneficial for a group of twelve young individuals with Cystic fibrosis in comparison with their normal chest physiotherapy routine.
Where is the research from?
This study was conducted at University Children’s Hospital, Graz, and Paediatric Department, Stolzalpe, Austria 1982. We can rely on this journal as a valid source as it is led by Dr Nick Brown whom is a clinician, epidemiologist and international child health expert.
This scientific journal is jointly owned by Royal College of Paediatrics and Child Health and BMJ who have a very broad international reach in terms of readership and editorially.
What kind of research was this?
This published original research article is a cohort study in which a group of individuals sharing defining characteristics, in this case children with Cystic Fibrosis, had the effects of physical activity analysed in comparison to their normal chest physiotherapy routine.
This particular type of research allowed M. Zach et al to perform a cross section at intervals over time observing the influence exercise had on a sample population all with the same diagnosis after seventeen days of exercise and the reversible outcome eight weeks post intervention.
What did the research involve?
Six boys and six girls with a median age of ten and a half years were sent to a paediatric rehabilitation hospital in a mountainous area in upper Styria (altitude 1180m above sea level). On the basis of a willingness to participate, positive sweat tests and a stable clinical condition the children were chosen from the Cystic fibrosis clinic at the University children’s Hospital, Graz.
During the seventeen day stay, the normal and strict routine of chest physiotherapy and aerosol inhalation were stopped. Instead, the children participated in an intense program of physical exercise and sport led by a chest physiotherapist. The activities involved; one hour of swimming and diving twice a day, a two-and-a-half-kilometre jog to and from the pool four times a day, hiking, gymnastics, swimming, minigolf, soccer and table tennis.
Ventilatory status of the children was assessed one day before admission, one day after the end of the hospital stay and eight weeks later. Data was collected by a qualified chest physiotherapist making results valid and reliable in comparison to other sources of data collection such as self-reporting.
To increase the accuracy of this study, a larger population of children could have been analysed as a larger sample group may have exhibited differing results. Measurement was only based off ten children; the two youngest patients did not cooperate sufficiently to obtain reproducible results making data collection from an even smaller group. Due to the study being undertaken in the Styrian mountains, this meant a higher altitude. A higher altitude means less oxygen to breathe which could potentially be advantageous as individuals are making greater adaptations in comparison to if the study were conducted in lower altitude such as Australia. A positive was the study conducted in the summer holidays in order to reduce any seasonal or occupational influences on clinical condition or pulmonary function.
What were the basic results?
M. Zach et al concluded that with all the activity a gradual increase in performance was evident in the children. As observed by the physiotherapist, frequency of coughing and volume of expectorated sputum decreased gradually to become only slight towards the end of the course. 
Demonstrated in the table below, it is evident from pre-exercise to post exercise that some of the more significant results such as forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and peak expiratory flow rate (PEFR) all saw an improvement. We can also notice that eight weeks after, without exercise the results almost returned to pretraining levels bar the PEFR in which only decreased slightly, potentially due to ventilatory muscle training. 
|Assessment day before submission||Assessment day after hospital stay||Assessment eight weeks later|
Clearly, enhancement of airway function depends highly on the upkeep of exercise. A limitation to these findings is that the training program was adjusted to the physical capabilities of the majority. Thus, it did not always adequately meet each child’s individual exercising capability. The ones who may have been able to cope with a more strenuous workload may have potentially had more effective results with a harder program. Ultimately, altering the methodology and individualising programs to suit individual needs could prove beneficial.
What conclusions can we take from this research?
It is apparent that physical activity in children could replace the regular inhalation-physiotherapy routine in some children with Cystic Fibrosis.
Similar to healthy populations, exercise training programs such as those aimed at improving aerobic fitness or muscular strength and endurance, are effective in children with Cystic Fibrosis.
Evidence suggests that exercise tolerance is severely limited by pulmonary mechanics in some Cystic Fibrosis patients.  Whilst these advanced stages of the disease may prove more risky than beneficial with major exertion, it is important that these physical activity interventions are modified to suit the individual needs of the patient depending on the severity of their diagnosis.
Although the value of each activity to improvement remains undefined, other sources suggest a similar pattern of improved pulmonary function was evident after a course of swimming lessons which may also be a cause of positive response in the experiment due to the participation in swimming and diving.
Consequently, a combination of physical activity and chest physiotherapy would be deemed most beneficial for individuals with Cystic fibrosis. However, the dependence on chest physiotherapy may decrease once adaptations and improvements are made through exercise.
Physical activity and sports provide abundant health benefits for individuals, hence Cystic fibrosis sufferers should not refrain from exercising nor be constrained from participation. Individuals who suffer from Cystic fibrosis should seek advice from health professionals on whether physical activity may be undertaken in regards to the severity of their condition.
A guide in which helps sufferers to exercise safely at home or in the community developed by Cystic Fibrosis WA can be found here- Cystic Fibrosis Exercise Guide. Another fantastic source the Cystic Fibrosis Foundation is great for diagnostic advice, care, and guidance for day to day living with Cystic Fibrosis.
For further information regarding Cystic Fibrosis as well as its link to exercise please use the following:
- Zach M, Oberwaldner B, Häusler F Cystic fibrosis: physical exercise versus chest physiotherapy. Archives of Disease in Childhood 1982;57:587-589.
- Cystic Fibrosis - What is CF [Internet]. Cysticfibrosis.org.au. 2019 [cited 7 September 2019]. Available from: https://www.cysticfibrosis.org.au/about-cf/what-is-cf
- Cystic fibrosis - Symptoms and causes [Internet]. Mayo Clinic. 2019 [cited 2 September 2019]. Available from: https://www.mayoclinic.org/diseases-conditions/cystic-fibrosis/symptoms-causes/syc-20353700
- Authority U. Cystic Fibrosis (CF) Treatment: Manual Chest Physiotherapy [Internet]. UWHealthkids.org. 2019 [cited 3 September 2019]. Available from: https://www.uwhealthkids.org/cf-center/cystic-fibrosis-cf-treatment-manual-chest-physiotherapy/34308
- Archives of Disease in Childhood | A peer review journal that keeps paediatricians and others up to date with advances in the diagnosis and treatment of childhood diseases. [Internet]. Archives of Disease in Childhood. 2019 [cited 6 September 2019]. Available from: https://adc.bmj.com
- Wilkes. D Et al: Exercise and physical activity in children with cystic fibrosis: Paediatric Respiratory Reviews. Volume 10, Issue 3, September 2009, Pages 105-109
- Godfrey S, Mearns M. Pulmonary function and response to exercise in cystic fibrosis. Arch Dis Child 1971; 46: 144-51
- ZachM S,PurrerB,OberwaldnerB.Effectofswimming on forced expiration and sputum clearance in cystic fibrosis.Lancet 1981; i:1201-3