Exercise as it relates to Disease/Sedentary behaviour risks linked to metabolic syndrome in rural Australia

A critical analysis of the article: associations of physical activity and sedentary behaviour with metabolic syndrome in rural Australian adults

Background
In 2012, 60% of Australian adults were not meeting physical activity (PA) guidelines. In 2018, 63% of people aged 18 and over are considered overweight or obese.

Rural Australia has been identified to have higher associated health risks with reportedly lower levels of PA, leading to higher presence of metabolic syndrome. An old data set may misrepresent populations as may not rely provide best current information about health associations related to diseases. Relying on outdated information may either under or overestimate the health of rural Australians.

Metabolic syndrome (MeTs) is defined as containing multiple cardiometabolic risk factors, increasing the risk of cardiovascular disease, type-2 diabetes and mortality. Risk factors include elevated blood pressure, cholesterol, triglycerides and blood glucose. As MeTs covers multiple risk factors, there are several classifications. The National Cholesterol Education Program, the International Diabetes Federation and a Harmonized definition representing a combined effort across both associations. While the Harmonized definition is not an official definition, the creation of it for the study was an attempt to examining multiple risk factors across the distinct definitions. Research indicates that increases to PA can reduce the risk of chronic disease, along with reduced sedentary behaviour, but in accordance to multiple defintions of MeTs.

Where is this research from?
The research was conducted within the Alliance for Research in Exercise Nutrition and Activity (ARENA) at the University of South Australia. The Australian Research council have given ARENA the highest ranking for research performance in sports and clinical science, indicating a reputable institution with field experts. Previous research by ARENA engage in PA within children and exercise regulation.

What kind of research was this?
The study was a cross-sectional analysis. Cross-sectional research analyses a population at a specific point in time with measurable results. A cross-sectional study is useful to investigate outcomes of MeTs while forming associations with PA and sedentary behaviour. A gold standard measure would be to compare data back to clinical definitions. A downside to a cross-sectional study is that they cannot be used to determine the cause of a disease as the data examined is from a set point of time.

What did the research involve?
171 participants were involved, aged between 18-70 from two rural regions in South Australia. Approximately a third (31.5%) of the Australia population is considered to live in rural areas. . The sample size may not accurately grasp the demographic represented, as only 2 regions do not account for most of the rural Australian landscape. The participants had physiological measures taken so they could be classified across three definitions of MeTs and were required to wear an accelerometer for a week.

What were the basic results?
6 main outcomes came as results from the study:


 * 1) Sedentary behaviour increased a risk of developing MeTs.
 * 2) Light PA and moderate-vigorous PA both reduced the chance or MeTs regardless of the definition.
 * 3) Light PA predicted MeTs independently to moderate-vigorous PA and total sedentary time.
 * 4) Sedentary time more than 30 minutes predicted MeTs independently of PA.
 * 5) The number of sedentary bouts predicted MeTs independent of light PA and moderate-vigorous PA.
 * 6) All three definitions of MeTs did not prove significant over each other as predictors.

What conclusions can we take from this research?
Significant associations are linked from sedentary time and PA with MeTs, both from this study and current data, with the frequency of PA to help reduce the chances of developing MeTs. Limitations within the study is that there is no guide for participants to follow regarding PA. Since it is a cross sectional study, data taken from one set point may reflect different in time and the results are only associations not causations. The key message is that the both PA and sedentary behaviour should be looked at separately, in that decreases to sedentary time and increases in PA are both activities that need to be adjusted to decrease the chances of developing MeTs. While the conclusions align with other information, the presentation is difficult to understand clearly, providing complicated results for a simple message.

Practical advice

 * Reduce Sedentary behaviour and increase physical activity by adhering to ESSA PA guidelines.


 * Ensure appropriate pre-screening measures taken when exercises are prescribed to monitor any risk factors or contradictions to exercise.


 * Study needs to assess effectiveness of lifestyle interventions.


 * As definitions change, behaviour predictors need to be monitored.

Further information

 * 1) ARENA: http://www.unisa.edu.au/Research/Sansom-Institute-for-Health-Research/Research/ARENA/
 * 2) Australian physical activity guidelines: http://www.health.gov.au/internet/main/publishing.nsf/content/health-pubhlth-strateg-phys-act-guidelines
 * 3) Metabolic syndrome Australia: https://www.healthdirect.gov.au/metabolic-syndrome