The largest study yet
This study was not just some small experiment, the researchers analysed data from 3,5 million New Zealanders. This makes it one of the largest ever cohort studies to examine the association between the mode of travel to work and mortality outcomes.
“We studied 80 % of the working-age population of New Zealand over a 15-year period, so it is highly representative,” said lead researcher Dr Caroline Shaw from the Department of Public Health at the University of Otago, Wellington.
70 % of people use their car
The study found that more than 80 % of people in New Zealand travel to work by car and only 5 % walk and 3 % cycle. The cycling group had the lowest mortality risk, about 13 % lower than those who walked or took public transport.
“There were gender differences in mode of travel to work, with 2 % of women cycling compared with 4 % of men, but more women walking or jogging (7 %), compared with men (5 %). A higher proportion of younger people cycled, walked or took public transport compared with older people.”
More cyclists are needed
Dr Shaw said that the findings give validation to initiatives that aim to increase the number of people commuting to work by bike.
“Increasing cycling for commuting to work in a country with low levels of cycling like New Zealand will require policies directed at both transport and urban planning, such as increasing housing density and implementing cycling networks.”
Walking didn’t have an effect on mortality
The study found no association between walking or taking public transport to work and a reduction in mortality. Perhaps that was influenced by the fact that the data provided no details about the physical intensity of the commute. This means that those who walked 200 metres to work were in the same category as those who walked for 30 minutes uphill to get to work.
Dr Shaw said there are also other reasons to promote these modes of transport. “Walking to work has physical-activity-related health benefits other than mortality reduction – including the prevention of cardiovascular disease and diabetes – and taking public transport has the benefit of emitting less carbon.”
