Using public transport instead of driving is healthier - according to a number of studies. People who use public transport do more physical activity, which is essential for staying healthy. According to the World Health Organisation (WHO), insufficient physical activity is the fourth biggest risk factor for mortality. The economic loss due to physical inactivity is also huge.
The risks of a sedentary lifestyle are well known. Physical inactivity can lead to premature death, heart disease, stroke , type 2 diabetes, colon cancer, breast cancer, reduced bone mass, depression and obesity.
Being overweight is the second most serious risk for Covid-19.
Overweight people are more likely to be admitted to intensive care and to remain infectious for longer than people of normal body weight. Hungary has more overweight people as a proportion of its population than almost any other country in Europe, and the situation has worsened since the start of the pandemic, with Hungarians gaining an average of 6.6 kilograms of weight.
Physical activity is not just about sports, leisure and recreational activities:
active daily transport is also a significant energy use for the body,
and not just in case of walking or cycling, but also when using public transport – as opposed to driving, where the body's energy consumption barely exceeds that at rest. This was shown, for example, by a study in Cambridge, UK, which measured the energy consumed by commuters who drove, walked, cycled or used public transport to get to work.
The study measured the energy consumption (MET) of 182 adults' bodies during their commute to work for one week using GPS and heart rate measurement.
The MET (Metabolic Equivalent of Task) expresses the amount of energy consumed by the body.1 MET = oxygen demand at rest. Each kilogram of body weight consumes 3.5 millilitres of oxygen per minute, i.e. the oxygen demand of our basal metabolic rate. An example of how MET is calculated - a 70 kg person walking briskly burns this many calories in 1 hour: 6 MET=6 kcal/kg/hour; 6 kcal/kg/hour×70 kg=420 kcal/hour.
The measured energy consumption is 1.28 MET for driving, 1.78 MET for bus travel, 4.61 MET for walking and 6.44 MET for cycling (energy demand at rest is 1 MET). The energy use of commuters by car was therefore significantly lower than for other modes of transport.
The energy use of public transport, while not approaching that of walking and cycling, also significantly exceeded that of cars.
An analysis of the health benefits of public transport by the Transport Policy Institute of Victoria in Canada found that in the US, where the vast majority of the population lives a car-dependent lifestyle, fewer than half of the adult population do the moderate-intensity physical activity - such as brisk walking - of at least 22 minutes a day recommended by the U.S. Centers for Disease Control and Prevention(CDC).
However, the majority of public transport commuters do this recommended amount by walking an average of 19 minutes a day to and from transit stations and stops,
and they are more willing to travel to destinations other than their daily commute by more active means than car driving. This amount of physical activity is well above the US average of just 6 minutes a day!
A study in New York City used pedometers and questionnaires to show that train commuters walked an average of 30 percent more, reported having walked for a period of 10 minutes or more, and were four times more likely to walk 10,000 steps a day than car commuters. Another study found that New York City residents have a much lower Body Mass Index (BMI) when they live in areas with higher densities of subway and bus stops, higher population density and more diverse land use.
Body Mass Index (BMI) is a measure to determine one’s weight category. It is calculated by dividing body weight in kilograms by the square of body height in metres (kg/m2).
A study, which looked at the walking habits of 1,237 randomly selected adults in the Seattle and Baltimore areas of the US, found that people who use public transport to get to work do on average 5-10 minutes more moderate-intensity physical activity per day and walk more to destinations around their homes and workplaces than people who drive – regardless of how pedestrian-friendly the neighbourhood is. A study in Atlanta also found that
people who use public transport walk more and for longer distances and are more likely to meet physical activity recommendations by walking than people who do not use public transport.
According to the analysis, public transport users walk an average of 1.7 kilometres a day, which is roughly two-thirds of the recommended amount of physical activity and ten times the daily distance walked by non-public transport users - which is just 160 metres. Public transport use increased walking activity for all income classes.
In another study, the relationship between commuting patterns and changes in BMI of nearly six thousand adults aged 40-69 years was followed for four years in Cambridge, England.
The BMI of those who changed from active or public commuting to car increased by 0.3, and those who changed from car commuting to active or public transport experienced the same level of decrease.
Australian researchers have modelled the health and economic benefits of increasing the frequency and coverage of public transport in Melbourne, Australia – a low density and sprawled city. Improvements to the public transport network would improve the physical activity of the population (by an average of 6.4 METs per week), reduce body weight, increase the number of healthy life years and reduce health costs.
Policy analysts have concluded that inadequate physical activity in the US causes 200 000 premature deaths a year and contributes to the low efficiency and high cost of health care compared to countries with similar economic performance. Sedentary lifestyle also hurt people's wallets: average annual medical expenditures are 32% lower for those who achieve physical activity targets ($1,019 per year) than for those who are sedentary ($1,349 per year). According to the aforementioned CDC, health expenditure directly linked to physical inactivity amounts to $117 billion (around 36,000 billion HUF!) a year.
Physical inactivity has a huge cost in Europe too: according to the UK's Centre for Economic and Business Research (CEBR), widespread physical inactivity costs the European economy more than €80 billion (nearly 30,000 billion HUF) a year – five billion euros more than the global spending on cancer drugs. In the WHO European Region (which includes the former Soviet republics too), physical inactivity is linked to around one million premature deaths a year.
Based on a large body of international research, the WHO has produced a 96-page recommendation on how to transform the structure and transport of cities to get people more physically active. One of its key recommendations is to
make public transport more attractive, since using public transport alone requires more physical activity than driving.
The Clean Air Action Group has already drawn attention to the links between car transport and physical inactivity on several occasions (for example in a study commissioned and approved by the Budapest Development Centre), but unfortunately these have not been widely publicised in Hungary. This must change without delay, as these are factors that fundamentally determine the health and lives of all of us.
This article was originally published in Hungarian on portfolio.hu.
Katalin Tarr
Clean Air Action Group