The town has been identified as the 28th most inactive place in England, with more than one in four adults not getting the recommended amount of exercise, higher than the national average.
Among children and young people in Barnsley - in the five to 18-year-old bracket - 46 per cent are classified as physically active according to the study carried out by Medicspot.
It is recommended that children and young people aged five to 18 should be physically active for an average of at least an hour per day across the week.
NHS guidelines advise that 75 minutes of vigorous intensity activity can give similar health benefits to 150 minutes of moderate intensity activity per week for adults, but 26 per cent of the town’s residents fall below the threshold according to the report.
Dr Johnson D’Souza, medical director at Medicspot, said: “There are many ways people in Barnsley can be more active, including riding a bike, brisk walking or pushing a lawnmower, all of which count towards the recommended 150 minutes of moderate intensity exercise for adults.
“Vigorous intensity activity makes you breathe hard and fast. This includes running, skipping, riding a bike uphill, and sports like football, rugby and netball.”
One in five reception-age pupils are now classed as obese in Barnsley - and the figure grows to almost one in three by the time they leave primary school.
The Rockingham ward is the worst-hit area according to the study, with a quarter of its four to five-year-olds obese, while Hoyland has 24.7 per cent, Wombwell has 17.7 per cent and Darfield fares better with a rate of 14.2 per cent.
However, the figures for ten to 11-year-olds, which is the age when a child leaves primary school, grow rapidly in each ward and although Hoyland has the highest rate of 34.5 per cent, Darfield’s children’s figures more than doubled to 30.4 per cent in that five-year period from reception to joining high school.
Medics in the report say a physically active lifestyle has been shown to help reduce risk of cardiovascular disease, coronary heart disease and stroke compared to those with a sedentary lifestyle.
Coun Jim Andrews, cabinet spokesperson for public health, said: “The proportion of Barnsley children who carry excess weight in reception is lower than the England rate, however the rate for ten to 11-year-olds is slightly worse than the rate, but not significantly.
“Compared to the other South Yorkshire authorities, Barnsley has the highest rate of four to five-year-old children who are a healthy weight.
“Barnsley Council’s food plan is about changing the food environment and culture within the town as well as improving access to quality food.
“Our approach focuses on developments to the policies and structures which we live, work, shop, eat and learn within, focusing on the social, cultural and environmental conditions around us.”