For women, barriers to physical activity can vary by weight

"What we see is that a woman with a higher BMI can face a double-bind of challenges to being more physically active," said the study's lead author Anna Adachi-Mejia.

In order to identify and measure barriers to physical activity among women, researchers used five BMI classifications: normal range with a BMI of 18.5-24.99: pre-obese, BMI of 25-29.99; obese class 1, BMI of 30-34.99, obese class II, BMI of 35-39.99, obese class III, BMI of 40 or greater. Study participants were asked a series of questions about their barriers to physical activity using two different approaches -- the traditional approach of using pre-worded survey questions, as well as an open-ended approach where respondents could write down their responses in their own words. The researchers then coded their responses to the open-ended approach questions into six categories: physical, psychological, social, resources, time and activity.

The traditional survey approach revealed that women perceived a range of barriers that varied by weight class with the perception of lack of self-discipline as a barrier regardless of weight class. In contrast, the open-ended approach revealed a different set of barriers that varied by weight class. Respondents, for example, described barriers of physical challenges such as injury that increased as weight class increased.

"I was surprised to hear about how often women wrote about physical impediment as being a barrier to physical activity," said Adachi-Mejia. "In those cases women don't need to hear more messages about their need to be more active. Instead, they need help with working through how to be more active in spite of having impairment. I hope that in future interventions we can integrate more physical rehabilitation and/or occupational therapy to help people work towards greater ability to be more active."