Exercise as it relates to Disease/Exercising at home to counteract physical restrictions in overweight populations suffering from Chronic Kidney Disease

This page analyses the article "Impact of home‑based aerobic exercise on the physical capacity of overweight patients with chronic kidney disease" Aoike, D., Baria, F., Kamimura, M., Ammirati, A., de Mello, M., & Cuppari, L. (2014)

Background
The authors investigated the effects of home based aerobic exercise with an overweight population suffering from Chronic Kidney Disease (CKD), as previous studies focused on healthy participants or weight loss. Further to this, investigation into a more accessible means of exercise was necessary as the barriers surrounding use of a gym or training facility, are far greater for obese populations than their healthy counterparts. The research was conducted through the University of Sao Paulo, utilising volunteer participants from Sao Paulo. All participants were considered obese, and were suffering from CKD however were not included if dialysis dependant.

The Authors
The authors of the article are all decorated academics within the health field. Of note is Marco Tullio De Mellio who has been involved in 432 research items, a staggering accumulation of knowledge and research within the field The team all have had prior involvement in researching nephrology of some form, be that in a healthy or disease state population.

A number of grants were successfully obtained by the authors, however these have not presented any form of conflict in interest. The grants were from; Foundation of Support to the Research of the State of São Paulo-Fapesp, Coordination for the Improvement of Higher Education Personnel (CAPES), Oswaldo Ramos Foundation and Center for Psychobiology and Exercise / Association of Fund and Research Incentive. It is important to note the research was conducted in Brazil, as Brazil is currently at risk of an obesity epidemic, therefore research of this nature is critical to the benefit of the entire Brazil population.

Research and Critique
This study was a correlation research task, whereby the authors set out to establish the relationship between the use of home based exercises and improvement in CKD patients' cardiopulmonary system. The study was a Randomly Controlled Trial (RCT) study, meaning that the delegation of participants into their respective protocols were randomly assorted. This methodology protects the results from a biased methodology. However, this does not completely protect the study, as participants were volunteers and therefore were presumably personally inclined towards the exercise portion of the study.

Participants were volunteers, who were not dialysis dependant and were considered sedentary, randomly allocated into two groups; one which would undertake a 12 week home-based aerobic fitness program, the other group were to be the control. The fitness program instructed participants to walk three times a week in a non-facility based environment such as walking down the street, or around the yard, maintaining a rate of exercise of 40-60% VO2. All participants undertook a variety of tests conducted prior to the research as a baseline and after the 12 weeks period had concluded. These tests included; The control participants were instructed to not undertake any exercise programs during this 12 week period (this was not unlike their usual lifestyle as participants were considered sedentary as a requirement for participation.
 * Cardiopulmonary test
 * Blood pressure test
 * Blood analysis tests
 * Dual energy x-ray absorptiometry scan
 * Functional capacity tests; arm curl test, back scratch test, sit and reach test

Methodology
The methodology generated a clear baseline understanding of the participants, forming a solid foundation to compare against the post-intervention results at 12 weeks. The methodology was well suited to the research task, as it has drawn on successful previous studies in the field to inform the methodology used. Indeed compared to other recent studies of the same topic, this particular article brings together an analysis of improved aerobic capacity alongside analysis of blood and clinical parameters such as blood pressure, body fat, and BMI. Whereas its counterparts selected only one of these parameters often.

Disadvantages of any RCT are the expensive nature of the task, both financially and time based. Further to this, because there are active interventions, the participants are required to volunteer to undertake the study, and high ethical consideration is required due to the presence of an active intervention. However, participant recruitment was well considered and ensured to not put these disease state participants at any great risk.

Conclusions
The below table illustrate the functional capacity results of the study. Overall, the study concluded an increase in aerobic capacity which was the desired outcome, this can be seen in the second table. Alongside this, were a variety of improvements in decreased blood pressure however there is some discussion to be had on the direct cause of this.

Functional Capacity Parameters at baseline and after 12 weeks of participation

Cardiopulmonary parameters at baseline and after 12 weeks of participation

As illustrated in the above tables, which detail only a snippet of the total results from the study, the participants who undertook the exercise program experienced improved health across all test categories. Of note is the exceptional improvement in VO2-peak and maximal ventilation capacity.

Important Findings and Interpretations
The researchers set out to identify the effects of aerobic exercise on obese participants suffering from CKD, not to determine if weight loss would aid in their physical state. One of the important findings of this research task, was observation of an improvement in peripheral vascular resistance, attenuation of sympathetic nervous system activity and vascular remodelling and attributing this to the improvement of aerobic capacity and not weight loss.

Results were not overemphasised, the authors interpreted them well, suggesting further research is required to understand the best course of action to help aid obese patients suffering from CKD. This research allows us to conclude that a home based, very simple aerobic exercise program, is able to improve the cardiopulmonary and functional capacity of overweight patients suffering from CKD. Further to this, additional research is required to determine what the best treatment is for overweight patients suffering from CKD, as currently there is conjecture as to the best means of aiding this population.



Advice and Insights
These findings aligned with current research, noting aerobic exercise increases the participants state of health.

My advice for the authors, is that it could have been more explicit in the aim of the article. While it explained it wanted to see the improvement of aerobic and cardiopulmonary capacity, this was almost a given outcome, as we know from studies with healthy individuals that any form of exercise will work to improve these areas. The area of research requires research to combine both ends of the spectrum that have been investigated to generate a rounded program to aid people suffering CKD and obesity in tandem.

Real-world implications of the research
This research will combine with those preceding it, to form the foundation for intervention programs to combat the foreseen obesity epidemic Brazil.

Further resources
Some further studies to consider are;

Aerobic exercise in obese diabetic patients with chronic kidney disease: a randomized and controlled pilot study (2009)

Obesity Epidemic in Brazil and Argentina: A Public Health Concern (2014)

Weight Loss Interventions in Chronic Kidney Disease: A Systematic Review and Meta-analysis (2009)

Physiological benefits of exercise in pre-dialysis chronic kidney disease(2014)