New Delhi, Aug. 20: Commuting to work using public transport instead of private vehicles can tangibly reduce body weight and the body’s fat stores, according to a new study that explored how the mode of daily travel can influence these health gains.
The study, conducted in the UK but considered relevant to India where private transport has grown over the past decade, has found that average-sized men could weigh 3kg lower and women 2.5kg lower if they used public transport instead of private vehicles.
Researchers at the London School of Hygiene and Tropical Medicine and University College, London, found that people who chose public transport, walked or cycled to work had lower body mass index and percentage body fat than those who used cars.
Their findings were published today in the British Medical Journal.
Several earlier studies have shown that active commuting translates into higher levels of physical activity. But the new research from the UK is being described as the first to use two objective measures — BMI and body fat percentage — through a sample of over 7,000 people.
“The findings are not entirely surprising, but they’re important,” said Anthony Laverty, a research associate at the department of primary care and public health at Imperial College, London, who was not associated with the study.
“This is a large study and it shows the health gains from active commuting are tangible even after correcting for the effects of diet and other physical activity by the commuters,” Laverty told The Telegraph.
The study found, after adjusting for age and other factors, men who commuted via public transport had BMI 1.05 and men who walked or cycled had BMI 1.01 points lower than among those who used private cars.
The BMI scores were 0.9 to 0.8 points lower among women who used public transport, walked or cycled. Similarly, the percentage body fat was also lower by one to two points among both men and women who used public transport instead of private transport.
“These two objective measures, when taken together, give a more accurate picture of body mass composition of individuals than previous studies,” Ellen Flint, a research fellow at the London School of Hygiene and Tropical Medicine who led the study, said.
“We’re therefore more confident about these findings,” she said.
The findings come amid forecasts that India’s population of private cars will more than double over the next 10 years and concerns that bus fleets steadily shrunk in Ahmedabad, Calcutta, Chennai, Delhi and Mumbai between 2000 and 2008.
“The proportion of people in our large cities opting for private transport is increasing,” said Anumita Roychowdhury, executive director for research at the non-government Centre for Science and Environment (CSE), New Delhi, who’s been tracking transport trends in India.
Roychowdhury was not associated with the UK study, but CSE has long been campaigning for investments and government policies that would discourage the use of private transport and encourage public transport.
Researchers suspect that efforts to promote active commuting in tropical countries such as India — where hot weather and high humidity are common — pose greater challenges than in temperate zone nations.
“But shading through vegetation and optimal street orientation could help improve thermal comfort in tropical countries,” Flint said. “These principles have been used in cities such as Taipei and Singapore to encourage active travel.”