Due to the rise in obesity, there has been increased interest in instruments that can monitor physical activity and movement. A study of such a device has yielded some surprising and useful results. It was conducted by the Movement Analysis Laboratory in conjunction with the Unit of Metabolic Diseases, Clinical Medicine Department, of the University of Bologna, Italy.
The device is called IDEEA (Intelligent Device for Energy Expenditure and Activity) and it is able to continuously record the physical activity and energy expenditure of the person wearing it. This device records the time spent stepping, walking, standing, sitting, reclining, and lying. It also records physical movements including speed, gait, cadence, and step length, among others.
For the study, researchers used 26 obese patients and 15 control subjects of a healthy weight. The goal was both to test the accuracy of the device and to find out if there are any differences in movement between obese and healthy weight people. Each participant was fitted with an IDEEA device and monitored for a 24 hour period. Subjects were told to go about their normal daily routine during the study period.
After 24 hours, they returned to the clinic for data downloading and processing.
The time spent doing physical activities was not significantly different between the two groups. Researchers observed that the obese patients walked less than the control group, although this difference was not statistically significant. A significant difference was found in cadence and speed of walking though. The obese patients walked an average of 93 steps per minute compared to 104 steps per minute in the control group.
The obese patients walked 66 meters in a minute while the control group walked 79 meters per minute.
Perhaps the most surprising results discovered are those relating to energy expenditure. It was found that the obese patients used significantly more energy to do the same task as someone of a healthy weight. The average energy expenditure for the control group was 1.78 calories a minute compared to 2.30 calories per minute in the obese group.
Because obese people use so much more energy to do daily tasks, they may tend to do less physical activity. This creates a cycle that is hard to break and inhibits weight loss activities. Previous research has also shown that the average energy expenditure is significantly greater in obese individuals.
The IDEEA device made this research project possible by providing accurate, objective information in evaluating physical activity. The main limitation of this device is that it is impossible to bathe or shower while wearing it. Considering the fact that the device must be calibrated before use, it is not something one can remove and then put back on after bathing. This limits the ability of the device to be used over a longer period of time.
The IDEEA device has potential to aid in preventing obesity as well as reconditioning obese people by objectively monitoring activity and energy expenditure. This information can then be used to develop individualized weight loss and weight maintenance plans.
Reference: Maria Grazia Benedetti, Annalisa Di Gioia, Linda Conti et al. Physical activity monitoring in obese people in the real life environment. Journal of NeuroEngineering and Rehabilitation. 2009;6:47
Study can be found at: http://www.jneuroengrehab.com/content/6/1/47