Bruce's Blog

Record low number of cyclists died in collisions in London in 2019

11/1/2020

Five cyclists died in collisions on London’s roads in 2019. This is much lower than the 2018 figure of 12. As shown in the diagram, it is half the average for the previous 5 years. Checking records back to 2002 shows this is the lowest figure over that period; it is probably the lowest figure ever.

A sample of 5 has a confidence interval from 1 to 11. This gives us cause to be cautious. However if we look at the trend it is much more convincing. The graph shows the trend since 2002.

The 2019 value looks like the continuation of a very real trend. The trend line estimate for 2019 would be 8, still the equal lowest value on record. The downward trend in fatalities is statistically very robust. Also remember that numbers cycling have increased substantially over this period, The trend shows lives lost falling steadily by 0.6 per year.
There are about 500,000 regular (several times a week) cyclists in London. So the risk of dying last year was 1:100,000. Is that a large risk? There are about 5 million people regularly walking about in London. Last year 71 were killed in road traffic collisions. This is a risk of 1:70,000. OK, last year had rather low cycle fatalities while the figure for pedestrians was higher than expected. But you can see that the risk of being a pedestrian is not much different from the risk of being a cyclist.
There is a clear message :

The risk of being killed while cycling is very low
This risk is falling steadily, year on year.

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Cycle flows along Quietway 1 – Pattern of arrival and departures

6/6/2019

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Cycle flows along any cycle route are dynamic. Cyclists join the route and leave the route. Here some data is presented about a short stretch of Quietway 1 in Bermondsey, South London.
Counts were mostly made in May 2019 at the time of peak am and pm flows. For some junctions we have large counts (around 1000) while at others only small sample counts were made (at least 53). It is best to take any values as liable to an error of at least +/- 20%. Flows are given as % max flow segment (Willow Walk). Actual peak flows at this site were: am, 1050; pm 650. For more information on flows and time trends, see https://southwarkcyclists.org.uk/quietway-1-cyclist-numbers-still-increasing/.
Key data is summarised in the Diagram above.
Patterns of joining and leaving are reversed in direction but otherwise quite similar for am and pm, presumably because many cyclists use the same route to work and homeward. Flows towards central London fell after Willow Walk. It is at this point that cyclists start to move off towards specific destinations often via the nearest bridges (London Bridge, Tower Bridge). Flows further out than Willow Walk increase as cyclists join Q1. For example at Oxley Close cyclists join from the south in the morning and leave in the evening, presumably taking routes to and from Peckham and Nunhead.
At the main junctions on this stretch between 12 and 36% of cyclists either leave or join. Q1 always keeps at least 64% of cyclists. Further out (not shown on the diagram) at the Surrey Canal Rd/Bridgehouse meadows junction the same pattern is seen. At this junction total flows in the evening approaching the junction are about half those on Willow Walk (312/hour). Around 77% of riders continue on Q1 along Surrey Canal Rd while 23% leave Q1 and continue across Bridgehouse Meadows.
A few counts are available for 2015-16. At the most central junction (Pages Walk) at the am peak 57% of cyclists left Q1 in August 2016, just a few months after the “official” opening. This is much higher than the 16% recorded in 2019. This probably indicates that, as cyclists found more of Q1, they switched routes, preferring to stay on Q1 longer. Or it may be that the many additional cyclists who now use Q1 (flows have doubled since 2016) do so because it continues for longer towards their destination. At the Oxley Close junction number joining the Q1 route has increased a small amount in 2019 compared with September 2015 (before Q1 created). This may be surprising as a feeder junction (Glengall Rd/Old Kent Road) was improved for cyclists in 2017. Although we should remember that the total numbers joining will have increased, just that as a proportion of the Q1 flows they have not changed.
Perhaps the most important general point to emerge from this analysis is to demonstrate how much joining and leaving there is. People use a designated route for the part of their journey where it suits them. But leave it as the near their destination, and join it taking routes from their personal starting point. In designing cycle routes it is essential to consider these aspects. We need to think about a network, not just single routes. It will never be possible for every origin and destination to have a designated route between them. Providing links to longer Quietways and other labelled routes is essential if we are to get maximum use from them. So consider the network, not just the A to B.

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A little more cycling, but same number of cyclists

15/1/2019

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Latest road traffic numbers for cycling in the UK
There is a clear analysis in the latest Road Traffic Estimates:Great Britain 2017. Have extracted page 1 and the cycling bits and attach them below. A valuable professional view that contrasts with the very optimistic statements of British Cycling, Cycling UK and others.
Total mileage is going up linearly, but at just 30% in 20 years, so about 1.5% each year. But numbers of cyclists are not going up. It is just the same number cycling a bit more each year.
We need to face up to the failure of the many initiatives to promote cycling and maybe think a bit outside the box. Bit more information and a chance to comment in the linked blog.
Looking more closely at the data shows that the increase in mileage is largely in Inner London. Away from Inner London the trend is very weak or zero. More on this in a later blog. Population surveys agree with the traffic data. Numbers of cyclists actually fell significantly over the first 2 years of Sport England's Active Lives Survey.
Seems to me important to face up to the failure of the many initiatives to promote cycling over recent years. Time to start thinking "outside the box".

road-traffic-estimates-in-great-britain-2017_cycling.pdf
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42% more female cyclists on quiet routes

24/10/2018

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Counts at peak time show that female cyclists comprise just 23% of the total. On quiet routes with little traffic the proportion is 42% higher than on routes with a lot of traffic. Counts were made in South Inner London. In Bermondsey on the main radial routes towards the City there were 18% female cyclists on the busy A200 route compared with 26% on the parallel Quietway 1. At the Elephant there was a difference between the 2 main roads where we counted. On Newington Causeway going south there is some segregation and a safe junction. Here there were 23% female cyclists. On London Road where there is no protection and a still dangerous junction there were only 16% female cyclists.

At the Elephant and Castle, after the changes, there were 19% female cyclists on 2 of the main roads compared with 28% on the quiet bypass route.

At the Elephant there was a difference between the 2 main roads where we counted. On Newington Causeway going south there is some segregation and a safe junction. Here there were 23% female cyclists. On London Road where there is no protection and a still dangerous junction there were only 16% female cyclists.
None of this is actually very surprising. But it does demonstrate clearly that if we want more cyclists from a wider demographic, improving the quality of cycle routes is an effective way to do this. And an important aspect of quality is not cycling alongside heavy motor traffic and not competing with it at junctions.
Raw counts in the Excel sheet below

proportion_female_busy_quiet.xls
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Cycling to work is as good for you as 5 gym sessions a week

7/11/2017

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2017 has seen 2 publications from the Danish GO-ACTIWE randomised control trial on the relative health benefits of cycling and gym exercising (refs at the end).
Overweight or obese, but otherwise healthy, 20-45 year-olds were recruited. They were randomly assigned to 4 groups: BIKE, taking up cycling to work (9-17km depending on baseline fitness); VIG and MOD, 2 groups doing 5 gym sessions a week at moderate or vigorous intensity; CON, a control group asked to carry on normal behaviour, but who were promised a free gym membership at the end of the trial. 130 people stayed the course for 6 months, of whom 21 were in the cycling group.

Not surprisingly aerobic fitness (VO2max) improved in the active groups, by 11% for the cyclists and 15% for the vigorous gym group (NB not a statistically significant difference between groups). Body weight fell slightly by 1.8% (2.9kg) in the cyclists and by a similar amount in the VIG group. Good news was that all the weight loss was fat. As shown in the diagram, fat mass fell by 2.1kg in the BIKE group, a 7% reduction. The Copenhagen research group also looked at markers of inflammation that are risk factors for coronary heart disease. One of these, C-reactive protein (CRP), fell by 34% in the BIKE group (and a similar amount in the VIG group).
These data are in line with previous work from longitudinal and cross-sectional surveys (e.g. see 21/4/17 and 2/12/16 blogs below). But they are important as this was a well-designed trial with tightly monitored interventions. So it adds significantly to the growing body of data demonstrating the health benefits of cycling. And although gym session were as effective as cycling, there is no question which option is cheaper and is easier to fit into a busy schedule
Sources
J S Quist, M Rosenkilde,M B Petersen, A S Gram, A Sjodin, B Stallknecht, Effects of active commuting and leisure-time exercise on fat loss in women and men with overweight and obesity: A randomized controlled trial, International Journal of Obesity accepted article preview 10 October 2017; doi:10.1038/ijo.2017.253.
A S Gram, E-M Bladbjerg, J S Quist, M B Petersen, M Rosenkilde, B Stallknecht. Anti-inflammatory effects of active commuting and leisure time exercise in overweight and obese women and men: A randomized controlled trial. Atherosclerosis 265 (2017) 318-324
M Rosenkilde, M B Petersen, A S Grama, J S Quist, J Winther,
S D Kamronn, D H Milling, J E Larsen, A P Jespersen, B Stallknecht. The GO-ACTIWE randomized controlled trial - An interdisciplinary study designed to investigate the health effects of active commuting and leisure time physical activity. Contemporary Clinical Trials 53 (2017) 122–129

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Southwark's Try-and-Ride Scheme

30/9/2017

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Southwark council's cheap bike loan scheme is not found by searching the Southwark web site or the site of Cycle Confident who run the scheme. This is very puzzling. This is a very good scheme for getting people started or restarted in cycling. Please let us know your experience with the scheme by Commenting on this blog post.

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Active travel in different ethnic groups

12/9/2017

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Key points

It is being claimed that Active Travel is lower in people of White British origin compared with those of Afro-Caribbean or Asian origin.
The basis of these claims is data from the Active People Survey.
Other, better-designed, surveys indicate that the white British grouping actually does more active travel than other groups.
It is important that we do not design programmes to increase active travel that focus on the wrong people.
All ethnic groups need to be encouraged to increase their active travel.
For cycling particular incentives need to be devised to get a higher proportion of Black and Asian groups into active travel by bike.

In the recent report on “Active Travel in Southwark 2017 - The health economic impact of walking and cycling (Southwark’s Joint Strategic Needs Assessment)” it was stated “People from White British ethnicity are least likely to take up active travel”. This information was going to play a part in targeting Southwark’s efforts to increase active travel. The source of this statement was a publication by the Dept for Transport, Local Area Walking and Cycling Statistics: England, 2014/15. In turn, this data was derived from the Active People Survey (APS) conducted by Sport England.

My understanding from other surveys of cycling and walking was that across the main ethic groupings, there was a higher proportion of cyclists in the white grouping and about the same walking rate across all groups. My concern was that the Active People Survey data might be unreliable, yet was likely to guide policy. This report re-examines at data from other surveys. The opportunity was also taken to look at London and Southwark, not just the national picture.

National Travel Survey (NTS)
This is the Dept of Transport’s annual survey of approximately 15000 individuals. The focus is on trips made for “transport” reasons. The proportions cycling once per month are much higher than the “Utility” data shown above from the AP Survey. This may be because the NTS sets broader criteria for transport riding than the APS did for “utility” riding.
The NTS data shows cycling in both black and Asian groups is well below the level in the white group. The pattern in London is the same as for Great Britain as a whole.

London Travel Demand Survey (LTDS)
This is a household interview survey carried out by Transport for London. 8000 face-to-face interviews are carried out each year, and interviewees also fill out a 1 day travel diary. All travel is covered, but leisure trips only account for 25% of the total, so the data represents largely “utility” cycling.
Analysis of trip mode shares gives the clearest indication of relative amounts cycing and walking done by different ethnic groups. Data was available for 9 years, 2005-2013.

Trip rate for the white British group is 3 to 4 times higher than for black or Asian groupings. This was true for Inner London and for Southwark. Data for Asians in Southwark is not plotted as the sample was too small.
The situation for walking is different. Walking trip rates are much more stable over time and differ little between ethnic groups

Census 2011 The census asks everyone about their main mode of transport to work.

Obviously transport to work is “utility”. The same pattern emerges as is seen in the NTS and LTDS. Cycling in the white British ethnic group is about 3 times the level in Asian or black ethnic groups. This is true at local, Southwark, level and at national level. Walking is more uniform, but there is still a clear trend for white British to walk to work more than Asian or black ethnic groups.

Why is the Active People Survey so out of line?
The Active People Survey is a random digit phone survey. This gives large numbers, but depends on reaching people via land lines. Large segments of the population have no land line, for example many young people. The APS survey team will try to compensate for this, but they have never published their method for doing so. As land lines have become less used, this problem can only have become more difficult to deal with. This methodology has in fact now been abandoned and a postal/internet survey with a proper population sample, Active Lives, has replaced the APS.

The other problem is with the question. Many people will find it difficult to distinguish “utility” from “leisure” cycling. It is notable that if you combine the APS data on utility and leisure cycling you end up with a situation closer to the other surveys.

Conclusions
The idea that white British are the ethnic group to target to increase active travel is clearly wrong. All ethnic groups need to be encouraged to increase their active travel. And for cycling particular incentives need to be devised to get a higher proportion of Black and Asian (and probably some other minorities) into active travel by bike.

Downloadable copy of above blog in Word format below

active_travel_in_ethnic_groups_critique.doc
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Cycling to work associated with massive health benefits

21/4/2017

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More analysis of the Biobank data, this time by Jason Gill and colleagues at the University of Glasgow and published open access in the British Medical Journal.
Data from 250,000 45-60 year-olds who were working full time, average follow up 5 years during which 0.75% of the non-active commuters died, but only 0.5% of the cyclists. After adjusting for time in study, age, smoking and lots of other possible confounding factors, the relative risk of early death if you cycled to work, compared with car or public transport, was 59%. So risk pretty much halved!
Looking at mortality just from cardiovascular disease or just from cancer gave similar risk reduction. Looking at incidence of cvs disease or cancer over a slightly shorter time also showed similar, nearly 50%, reduction in risk.
For relatively young people where the risk of dying is low, these are large reductions in a small risk. Presumably the study will continue and look at more than 5 years. It seems probable that the risk reduction will continue, but it will be good to see data showing a similar percentage gain when risk of dying is higher.
This is a cross-sectional study, so it could just be that fit, healthy people cycle to work, and the commuter cycling is just incidental. However, check my previous blog where research was described that showed improvements in health indices in individuals who started cycling to work.
The new study had data on the 5.4% who walked to work. They showed no reduction in mortality or incidence of cancer, although there was a small reduction in risk of developing CVS disease. Cyclists were also divided into those with long and those with short commutes. The longer commutes did better, but even the short distance commuters had a significant 32% reduction in mortality. Another sub-group were classed as "mixed mode: cycling", and comprised 4.8% of the sample. Tthis is therefore a larger group than the ones who travelled all the way to work by bike. This part-cycling commute group also showed significant (24%) reduction in mortality and a 32% reduction in incidence of cancer.
The authors point out: The data from this study......has important policy implications, suggesting that policies designed to affect a population level modal shift to more active modes of commuting, particularly cycle commuting (eg, cycle lanes, city bike hire, subsidised cycle purchase schemes, and increasing provision for cycles on public transport), present major opportunities for the improvement of public health.
And in the mean time, get on the Bike Train, Southwark Cyclists award-winning scheme of led rides to help people get started on cycle commuting.

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Active travel really is good for your health

2/12/2016

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We have known for a long time that people who exercise are fitter and healthier than those who do not. But were they born like that, or does regular exercise actually make you healthier, irrespective of your genes? The evidence is that it does, although your genes do play a part in even determining the effectiveness of exercise. But overwhelmingly, people who take up exercise get healthier.
So why do people not do enough exercise? “No time.” “Not my thing.” We have all heard the reasons. This is why active travel (walking or cycling) is such a good way to get exercise. It often saves you time and in addition it saves you money. And it helps the environment.
But does exercise in the form of active travel actually improve your health? We know from surveys that active travelers are healthier. But if you start commuting by active travel does your health improve? There have been a few small experimental studies that indicate that it does. But now we have some impressive evidence from two large scale surveys. Both studies looked at body mass index (BMI, kg/m2) a measure of how fat you are and a good index of general health and fitness.
The British Household Panel Survey ran from 1991 to 2009 and each year asked the 18,000 participants about how they travelled to work. From 2004-2007 they were also asked their height and weight, enabling BMI to be calculated. Over this period complete data was obtained from 4056 people of whom 109 switched from car travel to active travel (walking or cycling) and 156 switched the other way. For those switching to active travel, BMI fell by 0.32, equivalent to about a 1 kg reduction in weight. This may not sound much but the change occurred over about 1 year, not very long. And across the population, a reduction of BMI of this extent would be hugely helpful to an overstretched heal th service. Most impressive of all, the fall in BMI was greater the longer your commute (See chart above).
The few subjects who changed from the car to a greater than 30 min commute by walking or cyclinig had a BMI reduction of 2.25, equivalent to a 6kg (14lb – a stone!) fall in weight.
The British Household Panel survey also includes every year a questionnaire on psychological wellbeing (GHQ-12, questions on self-worth, ability to cope etc). Switching from car to active commute was associated with a significant improvement in wellbeing.
Data from the UK Biobank study shows a similar trend. The Biobank is a large database of 40-69 year-olds that includes BMI and mode of travel to work. Of the 500,000 participants, 20,000 have now had repeat measurements made, at an average 4.4 years interval. Of these, 5861 had data on commuting travel and all other relevant measures. The numbers switching from car travel to active transport or vice versa were too small for separate analysis (about 40 each way). So the analysis here is for a switch from car travel to either public transport or active transport and vice versa. Those abandoning their cars showed an improved BMI, on average 0.30 lower. In contrast those switching to a car commute put on weight, increasing BMI by 0.32. So changing travel mode triggered about a 1kg change in weight, down for those going to public or active travel, up for those switching to cars. See chart above).
These studies are important because they look at trends across large populations, so the statistical reliability is good. Lots of other data was also available about the survey participants so the analyses were able to allow for any possible bias due to differences in occupational status, working hours, household income, health status and a host of other factors that might influence the results. The Biobank study only analysed combined public and active travel. But we know from other studies that health indices in people using active transport are better than those using public transport, so the trend for both is very likely to include a similar or better trend for those switching to cycling and walking.
As a cyclist it would be even more interesting if these studies had contained separate data on cycling. Living in London where commute distances tend to be long, cycling is the time efficient option. Unfortunately not many people cycle to work. In order to find people who start cycling to work we would need an even bigger survey. The Biobank survey is ongoing and may eventually deliver enough data. But the message is clear. Active travel to work is good for your health and wellbeing.
Sources
Adam Martin, Yevgeniy Goryakin, Marc Suhrcke. (2104) Does active commuting improve psychological wellbeing? Longitudinal evidence from eighteen waves of the British Household Panel Survey. Preventive Medicine 69 296–303
Flint, ES; Cummins, SCJ. (2016) Is active commuting associated with obesity in mid-life? Cross-sectional, observational evidence from UK Biobank. The Lancet Diabetes & Endocrinology 4, 420-435
Ellen Flint, Elizabeth Webb, Steven Cummins (2016) Change in commute mode and body-mass index: prospective, longitudinal evidence from UK Biobank. Lancet Public Health October 28, 2016
Martin A, Panter J, Suhrcke M, et al. (2015) Impact of changes in mode of travel to work on changes in body mass index: evidence from the British Household Panel Survey. J Epidemiol Community Health 69:753–761.

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Two new cafes on Quietway 1

29/11/2016

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Two new cafes have appeared on the Q1 route, one at Dunton Rd and one 2 miles further east at Folkestone Gardens (see map).

Festa sul prato (translated “Feast in the Meadow” so think ‘Picnic in the Park!’) is a new, single storey, stand-alone building in Folkestone Gardens. You could miss it as the back is to the Quietway and is not signed. It is easily seen if approaching from Woodpecker Rd. Has been open since August 2016 and is rather smart. Currently as well as the food and drinks, some excellent art is being exhibited (Landscape-inspired abstract paintings by Louise Holgate, www.louise-holgate.co.uk).

Dropping in on a Tuesday afternoon had an excellent coffee. The choice of location was not determined by the closeness to the cycle route, but this was seen as a plus and there were 3 Sheffield stands by the entrance. Does a varied (Italian) menu, in fact feels more like a restaurant than a café. Lots of information on the Festa web site at www.festasulprato.com
Crol and Co will eventually be an antiques shop with an attached café. For now (only opened in October 2016) it is a café.

Location is a previously empty shop unit on the corner of Lynton Rd and Dunton Rd, so very visible from Q1. Bicycle rack outside with 2 bikes, and the owner is a cyclist. She commented on my Skyride Leader jacket and said she has ridden with her children on Skyrides. Again rather good coffee and lots of cakes and pastries on offer. On a cold Tuesday afternoon there were several small groups drinking coffee and looking very comfortable. Find out more on Twitter (#crolandcocoffee) or Instagram (Crolandcovintage).
What was interesting was that both businesses had noted the presence of the cycle route and saw it as a positive factor. The way cycle routes can increase local trade has been documented widely. There are some good examples from New York in Streetfight by Janette Sadik-Khan (Viking, 2016). Maybe, on a small scale, we are seeing the same thing here in South London. But whether this marks a new trend or not, we can still enjoy two valuable additions to the amenities of Quietway 1.

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Record low number of cyclists died in collisions in London in 2019

Cycle flows along Quietway 1 – Pattern of arrival and departures

A little more cycling, but same number of cyclists

42% more female cyclists on quiet routes

Cycling to work is as good for you as 5 gym sessions a week

Southwark's Try-and-Ride Scheme

Active travel in different ethnic groups

Cycling to work associated with massive health benefits

Active travel really is good for your health

Two new cafes on Quietway 1

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