Cycling and Public Health

A collection of academic papers and research, demonstrating the links between increased cycling and improved public health, and savings resulting therefrom.

NICE (National Institute for Health and Clinical Excellence) (2008), "Promoting and creating  built or natural environments that encourage and support physical activity" NICE Public Health Guidance 8http://www.nice.org.uk/nicemedia/live/11917/38983/38983.pdf This paper makes the case for policies to adjust the physical environment, so as to encourage an increase in physical activity. The authors note that physical inactivity has severe consequences both for public health and for expenditure -

In 2004, the DH [Department of Health] estimated that physical inactivity in England cost £8.2 billion annually (this included the rising cost of treating chronic diseases such as coronary heart disease and diabetes). It is estimated that a further £2.5 billion each year is spent on dealing with the consequences of obesity. Again, this can be caused, in part, by a lack of physical activity (DH 2004)

Also -

Physical activity not only contributes to wellbeing, it is essential for good health (DH 2004). Increasing physical activity levels in the population will help prevent or manage over 20 conditions and diseases. This includes coronary heart disease, diabetes, some cancers and obesity. It can help to improve mental health. It can also help older people to maintain independent lives.

The authors point out that the Department of Health's own recommended levels of physical activity are not being met by the majority of adults -

Adults are recommended to undertake a minimum of 30 minutes of at least moderate-intensity activity on most days of the week (DH 2004). Around 65% of men and 76% of women in England do not achieve this (Joint Health Surveys Unit 2004).

This is set against a background of a decline in rates of walking and cycling -

the distance people walk and cycle has declined significantly in the last 3 decades (Department for Transport 2007a). The average distance walked, per person per year, has fallen from 255 miles in 1975/76 to 201 miles in 2006. Bicycle mileage for the same years fell from 51 to 39 miles per person per year.

The paper argues that the national targets for physical activity can be achieved through walking and cycling as everyday activities; environmental factors that currently discourage walking and cycling need to addressed.

Adults, young people and children can achieve the national recommended levels by including activities such as walking, cycling or climbing stairs as part of their everyday life. However, while individual interventions to promote such activity may be important, they are not the only (nor possibly the main) solution. Other issues, including environmental factors, need to be tackled. As Schmid and colleagues say (1995), ‘It is unreasonable to expect people to change their behaviours when the environment discourages such changes’.

With this in mind, it has a series of policy recommendations for the creation and adjustment of the physical environment so as to boost physical activity, the most significant of which include -

Recommendation 1 [‘Strategy’)] - Ensure planning applications for new developments always prioritise the need for people (including those whose mobility is impaired) to be physically active as a routine part of their daily life. Ensure local facilities and services are easily accessible on foot, by bicycle and by other modes of transport involving physical activity. Ensure children can participate in physically active play.
Recommendation 2 [‘Transport’] – Ensure pedestrians, cyclists and users of other modes of transport that involve physical activity are given the highest priority when developing or maintaining streets and roads… Use one or more of the following methods: • re-allocate road space to support physically active modes of transport (as an example, this could be achieved by widening pavements and introducing cycle lanes) • restrict motor vehicle access (for example, by closing or narrowing roads to reduce capacity) • introduce road-user charging schemes • introduce traffic-calming schemes to restrict vehicle speeds (using signage and changes to highway design) • create safe routes to schools (for example, by using traffic-calming measures near schools and by creating or improving walking and cycle routes to schools).
Recommendation 3 –Plan and provide a comprehensive network of routes for walking, cycling and using other modes of transport involving physical activity. These routes should offer everyone (including people whose mobility is impaired) convenient, safe and attractive access to workplaces, homes, schools and other public facilities…. They should be built and maintained to a high standard.
Recommendation 5 [‘Buildings’] – Ensure new workplaces are linked to walking and cycling networks. Where possible, these links should improve the existing walking and cycling infrastructure by creating new, through routes.

Cavill, C. and Buckland, J. (2012), "Investigating the potential health benefits of increasing  cycling in the Cycling City and Towns" Department for Transport The focus of this paper is on the potential for health benefits from increased cycling in the Cycling Demonstration Cities and Towns (CCTs), and who, in particular, should be targeted. They estimate that

If all inactive people in the CCTs move up a level and become classed as moderately inactive, there would be around 600 fewer deaths within the CCTs per year.

If all the moderately inactive people in the CCTs become moderately active, the authors estimate there would be around 300 fewer deaths. These figures are for the CCTs alone. The authors stress that the most important health benefits are to be gained from encouraging those who are most inactive to become slightly more active; there are only marginal health gains in encouraging those who are already active to become even more active.

it can be seen that from the public health point of view, more would be gained in terms of impact on all-cause mortality from increasing cycling… among those who are currently inactive, than would be from getting moderately inactive people to do more, [and] nothing is gained in terms of all-cause mortality rates from increased activity levels among those who are already moderately active.

They note that for every 100 inactive people who die in a given year, only 83 moderately inactive people will die - there are substantial health benefits from only a slight increase in activity. The clear implication of the study is that we should focus our attention on creating environments that allow the most inactive people to become more active, and not on encouraging more exercise amongst the already active.

Oja et al. (2011) 'Health benefits of cycling: a systematic review' Scandinavian Journal of Medicine & Science in Sports, 21, pp.496-509 A review of the existing literature on the health benefits of cycling. The authors identified 16 cycling-specific studies. They write

Cross-sectional and longitudinal studies showed a clear positive relationship between cycling and cardiorespiratory fitness in youths. Prospective observational studies demonstrated a strong inverse relationship between commuter cycling and all-cause mortality, cancer mortality, and cancer morbidity among middle-aged to elderly subjects. Systematic assessment of the quality of the studies showed most of them to be of moderate to high quality.

Further

These studies suggest that there is a clear positive dose–response relationship between the amount of cycling and health outcomes: fitness improvement increases and the risk of all-cause mortality, CVD [Cardio-Vascular Disease] and colon cancer morbidity, and incidence of overweight and obesity decrease with increasing amount of daily cycling.

And

Cycling also protects against CVD risk in a dose–response manner. Cycling up to or over 3.5 h/week reduces the CVD risk by about 20%.

They conclude

While more robust research is needed to build a solid evidence base of the health benefits of cycling, the existing state of knowledge reinforces the current public health efforts to promote cycling as an important contributor to improving population health.

Andersen, L., P. Schnohr, et al. (2000) "All‐cause mortality associated with  physical activity during leisure time, work, sports, and cycling to work." Archives of Internal Medicine (11): 1621‐1628. http://archinte.jamanetwork.com/article.aspx?articleid=485349 A paper examining differences in all-cause mortality in Denmark as a result of various activities, including cycling to work.

Even after adjustment for other risk factors, including leisure time physical activity, those who did not cycle to work experienced a 39% higher mortality rate than those who did.

Rabi, A., de Nazelle, A. (2012) "Benefits of shift from car to active transport" Transport Policy 19(1), pp.121-31 http://www.sciencedirect.com/science/article/pii/S0967070X11001119 An article estimating the benefits accruing from a shift from car travel to walking and cycling, considering direct health benefits, health benefits for the general population from reduced air pollution, the effects of greater exposure to air pollution on walkers and cyclists, and the accident rate. Only mortality is considered in detail.

For a driver who switches to bicycling for a commute of 5 km (one way) 5 days/week 46 weeks/yr the health benefit from the physical activity is worth about 1300 €/yr, and in a large city (>500,000) the value of the associated reduction of air pollution is on the order of 30 €/yr.

There is an increased cost associated with greater exposure to air pollution, but this is highly variable, as is the cost associated with accident exposure. Data from Amsterdam suggests that

the (economic) loss due to fatal accidents is at least an order of magnitude smaller than the health benefit of the physical activity.

Yang, L. et al. (2010) "Interventions to promote cycling: systematic review" BMJ 341: c5293 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2957539/pdf/bmj.c5293.pdf A review of the literature on the effectiveness of various measures aimed at increasing cycling levels.

Evidence from observational studies suggests that changing the built environment has the potential to influence cycling behaviour, but few data from controlled intervention studies are currently available to confirm this. Our review shows that it is unclear whether increases in cycling could be achieved at lower cost by addressing attitudes and perceptions about cycling. Although individualised marketing of interventions to change travel behaviour appears to be effective— including in areas of Australia and the UK with little in the way of an established cycling culture—this approach is only applicable to people who are already interested in changing their behaviour. The claims made about the effectiveness of this approach should ideally be tested in an independent randomised controlled trial. At the same time, lack of supportive infrastructure might limit the willingness of people to take up cycling, particularly in areas without an established cycling culture.