Heart Foundation NSW Cardiovascular Health Director, Julie Anne Mitchell, described the figures, which show more than a quarter of us are obese, as alarming and sobering.

"Far from the image we often have of ourselves being fit, active and outdoorsy, this data shows that over a quarter of New South Wales residents (26.4 per cent) are obese and 55 per cent are living sedentary lifestyles with little or no physical activity in their day," she said.

Illawarra waistlines have been steadily growing over the past decade, with only an estimated one-third of the population at a healthy weight. Obesity is the second highest contributor to disease in a population where 24.3 per cent suffer cardiovascular disease.

The foundation wants a government commitment for strategies to get more people moving, such as easier access to public transport, healthy workplace policies, and to incorporate healthy design into town planning to encourage more recreational activity.

"Disturbingly, two out of three Australians aged 15 and over are either sedentary or do very little physical exercise.

"Heart Week is a timely reminder that heart disease can be prevented through modest but regular amounts of physical activity," Ms Mitchell said.

Annette Thornton runs a Heart Foundation walking group in Kanahooka, and also encourages more people to use their feet.

"It keeps everyone socially active as well as physically active ... we've got people [in the group] who have all different levels of fitness - it's good to do what you can," she said. "It makes you feel good and alive."

Some of the Kanahooka crew will join avid walkers from Kiama, Shellharbour, and Gerringong today in Bomaderry, for a Heart Week community walk and picnic day to celebrate 20 years of the foundation's walking community program. It will be held from 10am at Bomaderry Oval.