Exercise as it relates to Disease/A splash in the right direction for COPD sufferers

This Wiki-factsheet critiques the article, 'Effectiveness of Low-Intensity Aquatic Exercise on COPD: A Randomised Control', which was published in 2012 in the Journal of Respiratory Medicine. [1]

What is the background to this research?Edit

Chronic Obstructive Pulmonary Disease (COPD) is a progressive and irreversible lung condition, resulting in restricted airflow and abnormal inflammation within the respiratory tract. [2] Common risk factors for COPD include;

  • Smoking [1] [3]
  • Inhalation of air pollutants [3]
  • Occupational exposure [4]
  • Genetics (relating to an Alpha-1 Antitrypsin deficiency) [4]

It is estimated that by 2020, COPD will become the third greatest cause of death worldwide. [3] Additionally, there is currently no cure for COPD, hence it is imperative to understand methods which decrease symptom severity, improve quality of life and delay mortality.

Exercise and COPDEdit

Lung Foundation Australia suggest that exercise is 'one of the best treatments for COPD.' [4] However, limited research has been able to demonstrate the effectiveness of various types of exercise on decreasing the severity of COPD symptoms. Aquatic-Exercise reduces intensity and impact of exercise, allowing for improvements in cardiovascular and respiratory function whilst placing minimal stress on the body. [5] [6]

Research is particularly scarce regarding aquatic-exercise for COPD patients, hence this study aimed to identify potential benefits compared to traditional land-based therapy. [1]

Where is the research from?Edit

The article has been published within the Journal of Respiratory Medicine, an international peer-reviewed journal which is considered reputable. The authors originate from Brazil, however the location of the study is not specified. This has potential implications, as it is expected that country/demographic of origin would influence access to appropriate diagnostic tools, medications and treatment facilities.

No conflict of interest was declared.

What kind of research was this?Edit

This article conducted a randomised clinical trial (RCT). This form of study randomly assigns participants into either a control or study group, evaluating the effectiveness of a proposed treatment against a placebo/no treatment. [7] [8] It is believed that RCTs are the gold-standard of research, providing the 'highest level of evidence'; [8] eliminating potential selection bias and decreasing the impact of confounding factors upon the final results.[8]

Blinding refers to the concealment of information, regarding group assignment, from individuals in aspiration of reducing differential treatment and biased assessments. [9] The inclusion of blinding within methodology eliminates additional potential sources of bias, increasing the reliability of the study.

In this study, the 42 initial participants were randomly assigned into either the control or one of two study groups, thus eliminating selection bias. The use of blinding measures was not mentioned in this article, potentially reducing the confidence within the study. Blinding could potentially have been included by concealing group information from staff involved in assessment and additionally prescribing the control group participants with stretching exercises.

What did the research involve?Edit

The participants were divided into three groups - the control (CG), floor-based exercise (FG) or Aquatic-based exercise (AG). The activities of the CG were not stated. The FG and AG consisted of identical activities, with the AG activities adapted to use in a pool. Participants completed 24 x 1.5hr sessions over an 8-week period. Each session followed a protocol, as included below;

Table 1: Exercise Protocols [1]
Warm-Up - Unweighted upper and lower limb movements

(15 min)

Unweighted upper and lower limb movements

(15 min)

Conditioning - 1. Upper Body: weighted diagonal movements (2 min work: 2 min rest)

2. Lower Body: Stationary bicycle at predetermined intensity (30 min)

1. Upper Body: weighted diagonal movements (2 min work: 2 min rest)

2: Lower Body: Cycling motions with floats placed between legs,

at predetermined intensity (30 min)

Cool-Down - 15 min 15 min

By implementing identical FG and AG programs the study allowed for direct comparisons to be made, evaluating the effectiveness of the exercise setting, rather than other exercise variables.

Methodological Issues Within This ArticleEdit

Although group allocation was random to ensure transferability and reduce bias, it may potentially result in age bias, which may affect the findings - as ageing alters the state of the lungs.[8][1]

Another limitation to this study is the variation in group sizing. The exclusion of participants resulted in a discrepancy in group sizes; with the control group having almost twice the population of those in the AG (11 and 6 participants respectively).[1] Not only does this make inter-group comparisons difficult, it increases the variability and margin of error within the findings of the AG. Half of the exclusions in the AG were due to non-compliance, identifying issues surrounding accessibility (i.e. transport, costs, etc.) as a limitation. prompting the fact that issues surrounding accessibility are limiting factors to this mode of exercise.

What were the basic results?Edit

The results indicated that both FG and AG groups improved pulmonary function, respiratory strength and decreased their risk of mortality - demonstrated by the BODE Index. [10] In many of the findings the differences displayed between the FG and AG were insignificant, with the exception of the 6MWT where the AG displayed an average increase of  56m, (p=0.02). [1] The FEV1/FVC ratios for the AG and FG groups increased at similar rates, (~6-8%), whilst the CG value declined considerably by 5%, (p=0.05), [1]

What conclusions can we take from this research?Edit

This research demonstrated that participation in physical activity can improve lung function and decrease the severity and frequency of symptoms in COPD patients. The lack of statistically significant differences between both exercising groups eludes to the fact that the exercise setting is not important.

Effects of Aquatic-Based ExerciseEdit

Aquatic-based exercise has the ability to reduce impact and provide greater range of motion due to the buoyancy of the water.[5] Mooventhan and Nivethitha researched the effects of water immersion on body systems, determining that immersion in water of 25°C has the ability to improve oxygen consumption and, with repeated immersions, reduces the risk of respiratory infections - both of which are desirable for COPD patients. [6]

Despite these benefits, aquatic exercise is less accessible than land-based exercise and may be uncomfortable for those with body image issues. As there are minimal differences in the functional results obtained, patients may opt for land-based exercise instead. Supervised aquatic exercise is also quite expensive, hence patients may not be able to maintain participation long-term. To overcome these boundaries it is advised the patient begins with a supervised aquatic program and gradually progress towards unsupervised land activities, which are more maintainable.

Practical adviceEdit

In terms of ability to exercise, every participant should complete a Pre-Screening form prior to exercising. The ESSA Pre-Screening, is one example of the many available Pre-Screening techniques used in Australia. Although COPD is not explicitly listed in this Pre-Screening, Question 7 encompasses the condition indirectly. If this Pre-Screening were to be used, a COPD patient would need the approval of a GP and may require additional monitoring from an allied health profession to ensure safety during exercise.

Exercise AdviceEdit
  • Aquatic exercise has additional benefits of low impact, increasing Oxygen consumption and decreasing risk of respiratory infection
  • Land-based exercise is more accessible, affordable and practical, potentially increasing compliance
  • Participation in any low-intensity physical activity is beneficial to COPD patients, hence patient preference can determine the mode of exercise selected

Further ReadingEdit

The Lung Foundation; has constructed a guide for safe exercising for COPD patients and can be found here. Additionally they conduct patient support groups, locations can be found here.

Lungs in Action are community-based exercise classes for those with chronic lung conditions. To find a suitable location, visit: https://lungsinaction.com.au/class-locations/


  1. a b c d e f g h Trindae de Souto Araujo, Z., Angelica de Miranda Silva Nogueira, P., Emmanuelle Alves Cabari, E., de Paula dos Santos, L., Soares da Silva, I., Maria Molanda Ferrerina, G.. (2012). Effectiveness of low-intensity aquatic exercise on COPD: A Randomised Clinical Trial. Respiratory Medicine, 106(1), pp. 1535-1543.
  2. Mannino, D., Buist, A.. (2007.) Global Burden of COPD: Risk Factors, Prevalence, and Future Trends. The Lancet, 370 (9589), pp. 765-773
  3. a b c Hooper, R., Burney, P., Vollmer, W., McBurnie, M., Gislason, T., Tan, W., Jithoo, A., Kocabas, A., Welte, T., Buist, A.. (2011). Risk Factors for COPD Spirometry defined from the lower limit of normal in the BOLD project. UK: European Respiratory Society.
  4. a b c Lung Foundation Australia. (2018). COPD [Factsheet]. Retrieved from Lung Foundation Australia: https://lungfoundation.com.au/wp-content/uploads/2015/12/COPD_FS-Sep2015.pdf
  5. a b Enhance Physiotherapy. (2015). Benefits of Hydrotherapy. Retrieved from: https://www.enhancephysiotherapy.net.au/benefits-of-hydrotherapy/
  6. a b Mooventhan, A., Nivethitha, L.. (2014). Scientific Evidence-Based Effects of Hydrotherapy on Various Systems of the Body. North American Journal of Medical Sciences, 6 (5). doi: 10.4103/1947-2714.132935
  7. Kuper, C. (1982). Randomised Clinical Trial.  Japanese Journal of Ophthalmology, 26 (3), pp. 241-247.
  8. a b c d Brighton, B., Bhandari, M., Tornetta, P., Felson, D.. (2003). Hierarchy of Evidence: From Case Reports to Randomised Controlled Trials. Clinical Orthopaedics and Related Research, 413 (1), pp19-24.
  9. Faber, J., Fonseca, L.. (2014). How sample size influences research outcomes. Dental Press Journal of Orthodontics, 19 (4). pp. 27-29
  10. Celli, B., Cote, C., Marin, J., Casanova, C.. (2004). The Body-Mass Index, Airflow Obstruction, Dyspnea, and Exercise Capacity Index in Chronic Obstructive Pulmonary Disease. The New England Journal of Medicine, 350 (10), pp. 1005-1012.