A new study from Brigham Young University has confirmed the idea that obesity leads to a decline in physical activity.

The study had really no surprises, but what it offers is a deeper understanding of how obesity slows people down and more importantly, how this cycle of obesity and poor physical activity can be broken.

"Most people talk about it as if it's a cycle. Half of the cycle has been studied almost without limit. This is the first study of its kind, in many ways, looking at obesity leading to decreases in physical activity over time," said exercise science professor Larry Tucker from Brigham Young University and senior author of the study.

The study was based on data obtained from 250 people, of whom 124 were obese. All participants had to wear accelerometers that monitored activity levels.

The participants were asked to wear the accelerometer continuously for a week and then for another week 20 months later.

Study results showed that while non-obese people had no change in physical activity levels after 20 weeks, obese people, on an average, had a decrease of 8 percent in physical activity.

"It's not rocket science, and it's very logical. It just hasn't been studied using high quality measurement methods and with a large sample size. This provides scientists with more ammunition to understand how inactivity leads to weight gain and weight gain leads to less activity. This cycle, or spiral, is probably continuous over decades of life," Tucker said in a press release.

The study is published in the journal Obesity.