Exercise as it relates to Disease/The relationship between occupational choice and obesity in adults

This is an analysis of the journal article "Cross-sectional associations between occupational and leisure-time sitting, physical activity and obesity in working adults" by Chau et al. (2012)



What is the background to this research?
Obesity is a condition that is related to having excess body fat, it can be affected both genetically and environmentally. The Body Mass Index (BMI) is a widely used measure to determine body fat based on an individual’s height and weight, it calculates whether you are in a healthy weight range. Obesity is classified when your BMI is at 30 or above.

Prevalence
In 2011- 2012, 62.8% of Australians aged 18 years and over were classed as overweight or obese. This consisted of 35.3% being overweight and 27.5% being obese. The prevalence of overweight and obesity has continued to increase within Australia from 56.3% in 1995 and 61.2% in 2007-2008.

Where is the research from?
The study was conducted using data from individuals that completed the 2007-2008 Australian National Health Survey (NHS). The NHS is a nationally recognised survey of adults living within Australian households.

What kind of research was this?
A stratified multistage sample design was used to collect the data for this study, with a sample made from both urban and rural areas. All of the surveys were conducted face to face using a computer assisted interview.

What did the research involve?
Secondary analysis of the existing data took place and the study only used the following:
 * Resident’s aged 15 to 69 years
 * Residents that worked either full time or part time.
 * A total of 10,785 people which was made up of 5807 men and 4978 women.

All participants had their weight and height measured and their BMI were calculated from this. Each participant was interviewed and reported the following:
 * Their usual activity at work out of the following options: mostly sitting, standing or walking, mostly heavy labor or physically demanding work.
 * The time spent sitting during leisure time on a usual week day, however full time workers reported how long they spent sitting at work during the day.
 * The total time spent participating in fitness activities such as recreation within the past week, as well as duration spent taking part in ‘moderate to vigorous’ physical activity.
 * If they walked for transport for more than 10 minutes at a time, if so for how long in total for the week.
 * A self-report including the following: sex, age, highest level of non-school education, work status, hours of work a week and occupation.
 * If they successfully participated in 150 minutes of physical activity over the duration of the week.

Additional comments

 * Due to the bias nature that can be seen within self-reporting, such as over-reporting and under-reporting from the participants i.e. the participant saying they do hours of exercise when in reality they do very little, the results from this data may be skewed likewise with other studies.
 * Each individual may have a different understanding as to what ‘moderate to vigorous’ exercise involves therefore false information may have been recorded.

What were the basic results?
Results explained that a large proportion of both males and females mostly sit or mostly stand at work. The occupations with the greatest measure of participants mostly sitting at work were managers, administrative workers, and machinery operators (white collar workers) and occupations with the lowest amounts of mostly sitting were labourers, technicians or trade workers (blue collar workers). On average, full-time workers reported to be sitting 3.8h/day whilst at work and sitting 3.4h/day during their leisure-time. The mean BMI of full time workers was 26.7 kg/m2, this being ranked as ‘overweight’.

The average time spent sitting during leisure was very similar for all workers both full time and part time at about 3.4h/day. Although, results showed that workers with mostly sitting jobs, white collar workers, tended to be more physically active during their leisure-time in comparison to the blue collar workers. Participants with less than 4h/day of leisure-time sitting were seen to have a considerably lower risk of being overweight or obese in comparison to participants that spent more than 4h/day sitting during leisure time.

The research has explained that individuals with occupations involving mostly sitting have a much greater risk of being overweight or obese in comparison to individuals that are more active at work. Also, sitting for numerous hours per day during leisure time has an obvious relationship with obesity risks.

What conclusions can we take from this research?

 * This study provided evidence that occupation choice could be an effective intervention to increase physical activity levels in the adult population, which can lead to health benefits such as a lower risk of being overweight or obese.
 * The choice of research methodology is important to collect accurate data, as said previously, the results may be bias within this study due to the choice of self reporting.
 * All participants taking part in a research intervention need to know exactly what is involved and what everything means to ensure true data. Such as, individuals may have had their own understanding on ‘moderate to vigorous exercise’ in this study.

Practical advice

 * Individuals should consider the physical activity that is involved within their chosen occupation as it may positively or negatively affect their health.
 * Take note that if you want a lower and healthier BMI you need to consider an active job as well as participate in physical activity during leisure time.
 * If you believe your occupation is not overly physical, you should consider increasing the time and intensity spent on physical activity during leisure time to compensate this.

Further information/resources
For further information and support on obesity and its relationship with physical activity, click on the links below:
 * More than half of adults are overweight and the numbers are increasing -http://www.abs.gov.au/ausstats/abs@.nsf/Latestproducts/4719.0Media%20Release12004-05?opendocument&tabname=Summary&prodno=4719.0&issue=2004-05&num=&view=
 * Weight Management: Obesity - https://www.betterhealth.vic.gov.au/health/healthyliving/obesity
 * Obesity and Overweight - https://www.nhmrc.gov.au/health-topics/obesity-and-overweight
 * Obesity Prevention Initiatives - http://www.cancervic.org.au/preventing-cancer/weight/obesity-programs