I’ve talked before about the importance of attitudes and expectations in determining the effectiveness and outcomes of physical activities, and perhaps this may be one of the mechanisms at work that produced the unexpected results in the study above.
I strongly believe that the overall effects to your health of an activity such as running 5km can be strongly influenced by your perception.
For example, if you run 5km because you feel you have to in order to try and lose weight or avoid heart disease and it is a chore, or if you run the 5km but are frustrated and depressed afterwards because it was slower than your pb or Joe Bloggs at the gym, you would not get the same benefits had you run the exact same distance, in the exact same time, but had simply enjoyed being in the moment, preferably in nature.
Could it be that if you do have a physical job, that by changing your attitude at work, you could glean more benefits? I have long thought that in our service culture, manual labour has been unfairly looked down on as inferior to white collar work, despite the fact that in many cases it is probably more essential and requiring equal if not more skill.
Of course this is all pure speculation. The study is purely observational, and despite efforts to control for confounding factors, this is never really possible, and there are probably far more than you can shake a stick at!
Also, it is quite likely that the manual tasks required at work are highly repetitive and not particularly mentally stimulating (though of course the same is probably true for a lot of people’s leisure activities.
My advice would be that if you do have a manual job, try and apply some MovNat philosophy too it:
- Be in the moment
- Take pride in your work
- Enrich your environment – Make up games and challenges
- Work on honing your skills – Come up with new and innovative ways to perform your tasks
Also, ignore this study and believe the activity is doing you good, and at the very least you may get a placebo effect…
EDIT: Having written this post yesterday, I recalled last night a study I saw a few years ago in female hotel workers on this very subject. Here’s the abstract:
ABSTRACT—In a study testing whether the relationship between exercise and health is moderated by one’s mindset, 84 female room attendants working in seven different hotels were measured on physiological health variables affected by exercise. Those in the informed condition were told that the work they do (cleaning hotel rooms) is good exercise and satisfies the Surgeon General’s recommendations for an active lifestyle. Examples of how their work was exercise were provided. Subjects in the control group were not given this information. Although actual behavior did not change, 4 weeks after the intervention, the informed group perceived themselves to be getting significantly more exercise than before. As a result, compared with the control group, they showed a decrease in weight, blood pressure, body fat, waist-to-hip ratio, and body mass index. These results support the hypothesis that exercise affects health in part or in whole via the placebo effect.
Here’s a link to the full text: Mind-Set Matters: Exercise and the Placebo Effect Alia J. Crum and Ellen J. Langer (2007)