Nearly three quarters of people did manage a weekly ten minute stroll, meaning West Sussex still had a higher rate of regular walkers than the rest of the country, where the average was 68%.
The figures come from the Active Lives Survey, an annual questionnaire which asks people over the age of 16 in every local authority in England about how much sport and physical activity they do.
The survey also found that 18% of people in the area did not walk for ten consecutive minutes in the last month.
But 33% walked for ten minutes or more at least five times a week.
People in urban areas were more likely to walk as a mode of transport than those in the countryside, according to the survey, which found nine out of ten areas with the highest number of adults walking for travel were in London.
In rural areas, people were more likely to walk as a leisure activity rather than for travel.
In West Sussex, more than half of respondents walked for leisure once a week. This was higher than the 41% who took at least one weekly walk for travel.
The local authority which had the highest rate of weekly walking was the City of London, followed by Hammersmith and Fulham. Sandwell in Birmingham had the worst rate of weekly walking - just 56% of adults surveyed managed a ten minute stroll.
The NHS recommends that all adults take 150 minutes of moderate exercise, such as brisk walking, every week. It says regular walking reduces the risk of high blood pressure, high cholesterol, and type 2 diabetes, as well as helping maintain a healthy weight.
The latest figures from Public Health England show that 61% of adults in West Sussex are obese or overweight.
An NHS report on physical activity found people are leading less active lives than in previous decades, due to factors like increased car ownership and a reduction in the number of manual jobs.
“For most people, the easiest way to get moving is to make activity part of everyday life, like walking or cycling instead of using the car to get around”, the guidance says.