The prevalence of obesity in the Western world is continuously increasing and the amount of obese persons among the adult population in the United States is now 35%. As a result of this growing problem, it is important and necessary to find an efficient way to prevent further weight gain in the population.Physical activity is one of the key strategies used by public health agencies to combat the growing burden of non-communicable diseases. As a result adults around the world are recommended to engage in at least 150 minutes of moderate or 75 minutes of vigorous intensity activity per week, or a combination of moderate or vigorous activity that results in approximately the same total energy expenditure. However, majority of the population does not meet the physical activity recommendation. As barriers to physical activity, people mostly cite lack of time, self-motivation and confidence in the ability to be physically active.~Recently, using the HUNT study data, the Cardiac Exercise Research Group devised a simple metric termed Personal Activity Intelligence (PAI) which, using individual heart rate patterns of the body, estimates the optimal threshold of physical activity required for a specific objective: to decrease risk of premature death in an individual from the general population. The idea is to keep the weekly PAI score above 100. Since PAI is a personalized reflection of the body's response to physical activity based on heart rate, PAI score of 100 is specific to an individual. For example, a 100 PAI for a fit person is not the same as 100 PAI for an unfit person. PAI can be accumulated over a course of one week using physical activity of personal preference (i.e. walking, swimming, dancing, playing with grandchildren etc.) and allows for days with no activity as long as they are followed up by days of higher activity. However, the optimal amount and intensity (i.e. the number of PAI) of physical activity that would help for weight gain prevention still remains to be determined.
Physical activity is one of the key strategies used by public health agencies to combat the growing burden of obesity and non-communicable diseases. Adults around the world are recommended to engage in at least 150 minutes of moderate or 75 minutes of vigorous intensity activity per week, or a combination of moderate or vigorous activity that results in approximately the same total energy expenditure. However, majority of the population does not meet the physical activity recommendation. As barriers to physical activity, people mostly cite lack of time, self-motivation and confidence in the ability to be physically active. Cardiac Exercise Research Group (CERG) at Faculty of Medicine and Health Sciences at Norwegian University of Science and Technology recently developed Personal Activity Intelligence (PAI). PAI is a result of research based on the HUNT study where more than 60 000 individuals has been monitored over a period of more than 20 years. The goal is to make PAI the new world standard of activity tracking. PAI is an individual metric that makes sense of measured heart rate data, and significantly reduces the risk of lifestyle related diseases.~The purpose of the study is to obtain new knowledge about how the use of PAI is related to body weight.