Commuting by car or public transportation, compared to walking or cycling, is associated with negative effects on health, researchers in Sweden found. Erik Hansson of the Faculty of Medicine at Lund University tracked 21,000 people, ages18-65, who worked more than 30 hours a week and commuted either by car, train or bus, or were active commuters, who traveled by walking or cycling. \"Generally car and public transport users suffered more everyday stress, poorer sleep quality, exhaustion and, on a seven-point scale, felt that they struggled with their health compared to the walkers or cyclists,\" Hansson said in a statement. \"The negative health of public transport users increased with journey time. However, the car drivers who commuted 30 to 60 minutes experienced worse health than those whose journey lasted more than one hour.\" The drivers with the longest commutes tended to be men and high-income earners who traveled from rural areas -- a group that generally consider themselves to be in good health, Hansson said. \"More research needs to be done to identify how exactly commuting is related to the ill health we observed in order to readdress the balance between economic needs, health and the costs of working days lost,\" Hansson said. The findings were published in the journal BMC Public Health.