9 Undisputed Facts About the Benefits of Cycling (And the Thing Nobody Measured)

There is a person I keep meeting. You probably know them too. You might be them.

They want to start cycling. They've wanted to for about three years. And every time they get close, they open a laptop instead of a shed door, and forty minutes later they've got eleven tabs open and a spreadsheet comparing groupsets, and they've concluded that the bike they'd actually need costs £1,400, which they can't justify this year, so they'll start properly next year.

Meanwhile there is a bike in the shed. It's a hybrid from Halfords or a mountain bike from 2011 or something inherited from a relative. It has a slow puncture and a saddle at the wrong height and it is, apparently, the wrong bike.

I want to make an argument in this piece, and I want to make it with evidence rather than encouragement, because encouragement is cheap and everyone's had plenty.

Here it is. The largest and most-cited studies on cycling and health, run in different countries across three decades, keep finding the same thing: people who ride bikes live longer, age better, get ill less and enjoy their day more than people who don't. And not one of those studies asked what bike anyone was riding.

This is a long one, because I wanted every number in it to be checkable. Every study is linked where it's mentioned and listed again at the bottom.

It keeps you alive

The big one is Celis-Morales and colleagues, published in the BMJ in April 2017. It used UK Biobank data: 263,450 people recruited from 22 assessment centres across England, Scotland and Wales, followed for a median of five years. Ordinary working adults, mean age 52.6, going to work.

The researchers sorted them by how they got there (car or public transport, walking, cycling, or a mix) and then waited to see what happened to them. Over the follow-up, 2,430 people died. There were 1,110 cardiovascular events and 3,748 cancers.

Compared with people who drove or took public transport, the cycle commuters had:

• 41% lower risk of dying from any cause (hazard ratio 0.59)
• 46% lower risk of developing cardiovascular disease (0.54)
• 52% lower risk of dying from cardiovascular disease (0.48)
• 45% lower risk of developing cancer (0.55)
• 40% lower risk of dying from cancer (0.60)

Those are enormous numbers. There is no pill that does that. Walking to work, for comparison, was associated with a lower risk of cardiovascular disease in the same study, but not with lower all-cause mortality. The cyclists were the outliers.

You don't have to do all of it

The figure I actually want you to take away is a different one, and it's the most generous thing in the whole paper. The study had a category called mixed mode: people who cycled part of the way and took the train or the bus for the rest. The half-measure. The compromise. The thing you do when the full commute is too far or too wet or too much.

Mixed-mode cycle commuters still had a 24% lower risk of dying from any cause (0.76), a 36% lower risk of developing cancer, and a 32% lower risk of dying from one.

You do not have to do all of it. You do not have to do it properly. Riding to the station counts.

It isn't a one-off

One study, however big, is one study. So it's worth knowing that the UK Biobank paper is the middle of three, from three countries, across three decades, that all point the same way.

The first was in Copenhagen, published in the Archives of Internal Medicine in 2000. Andersen and colleagues followed 30,640 randomly selected Danes aged 20 to 93 for an average of 14.5 years. Their conclusion, in their own words: bicycling to work decreased the risk of mortality by "approximately 40% after multivariate adjustment, including leisure time physical activity". In other words, the benefit held even after accounting for how active people were the rest of the time. The commute itself was doing the work.

The most recent came from Imperial College and Cambridge, published in The Lancet Planetary Health in 2020. Patterson and colleagues linked census records for more than 300,000 commuters in England and Wales and followed them for up to 25 years, from 1991 to 2016. Compared with people who commuted by car, cycle commuters had a 20% lower rate of death from any cause, a 24% lower rate of cardiovascular death, a 16% lower rate of cancer death and an 11% lower rate of being diagnosed with cancer at all.

The sizes differ. The direction never does.

It keeps you young, in a very specific way

The next study is smaller and stranger and I like it enormously. Duggal, Pollock, Lazarus and colleagues, published in Aging Cell in 2018, a collaboration between the University of Birmingham and King's College London.

They took 125 cyclists aged 55 to 79, compared them with 75 inactive people of the same age and 55 young adults, and went looking inside their immune systems.

Here's the bit worth knowing. You have a gland behind your breastbone called the thymus. It makes T cells, the part of your immune system that learns to recognise things it hasn't met before. In everybody, the thymus starts shrinking at about the age of 20 and keeps going. By the time you're old it's producing very little, which is a large part of why older people get iller from infections and respond less well to vaccines. It's considered one of the more inevitable parts of ageing.

The cyclists' thymuses hadn't got the message. Their frequency of recent thymic emigrants (brand-new T cells, freshly made) was no different from the young adults'. They also had higher levels of IL-7, a signalling molecule that protects the thymus, and lower IL-6, which shrinks it.

Now, the honest caveat, because this study gets over-reported and I'd rather you had it straight. These were not people pootling to the shops. To qualify, the men had to be able to ride 100 km in under six and a half hours and the women 60 km in under five and a half, and they had to have actually done it at least twice in the three weeks before testing. That's a keen amateur. It is not a casual rider, and anyone telling you a fifteen-minute ride to work rebuilds your thymus is going beyond what was measured.

What the study does establish is that the decline isn't a law of nature. It tracks what you do. And, this matters for my argument, the paper is about people who kept riding for decades. It says nothing whatsoever about what they were riding while they did it.

There's a gentler companion study from the University of Reading, published in PLOS ONE in 2019. Leyland and colleagues took 100 adults aged 50 to 83 who weren't regular cyclists, gave 36 of them a bike and 38 an e-bike, kept 26 as a non-cycling control group, and asked the riders to cycle at least three times a week for half an hour for eight weeks. Both cycling groups improved on tests of executive function compared with the controls. Eight weeks. Three rides a week. People who had never thought of themselves as cyclists.

It's not too late to start

The objection I hear most from people over fifty is that the window has closed. A Danish cohort answers that directly.

Rasmussen and colleagues, PLOS Medicine, 2016, followed 52,513 Danish men and women aged 50 to 65 for an average of 14.2 years, watching for type 2 diabetes. People who cycled regularly throughout had a 29% lower risk than non-cyclists (hazard ratio 0.71). Commuter cycling on its own, at any dose, was associated with a 17% to 30% lower risk.

But the finding I keep coming back to is this one. The researchers went back to everybody five years in and asked again. People who weren't cycling at the start and had taken it up by the second questionnaire, in their fifties and sixties, had a 20% lower risk of type 2 diabetes than the people who never started (0.80).

They weren't asked what they'd bought. They were asked whether they rode.

It turns the worst part of the day into the best part

The next one isn't about your body at all.

Kiron Chatterjee's team at the University of the West of England spent eighteen months going through Understanding Society data on more than 26,000 workers in England over a five-year period, looking at what commuting does to how people feel. The peer-reviewed version is Clark, Chatterjee, Martin and Davis in Transportation, 2020.

The headline finding is bleak and very funny. Every additional minute of commuting reduces job satisfaction and leisure-time satisfaction, increases strain and worsens mental health. An extra twenty minutes of commuting a day hits job satisfaction about as hard as a 19% pay cut. Read that again if you drive to work.

Bus passengers came off worst. And the exception, the group for whom a longer commute didn't do the same damage, were the people walking and cycling, because for them the commute was doing a second job. It wasn't dead time being endured between the two useful parts of the day. It was the exercise, the daylight and the thinking time, all folded into a trip they had to make anyway.

That's the thing I'd struggle to talk anyone out of. For almost everybody, the commute is a tax. For one group it's the best twenty minutes they get.

Nobody asked what bike

Here is the hinge, and it's the whole reason I wanted to write this.

Go back through every study above and look for the question that isn't there.

The 6,751 cycle commuters in the UK Biobank analysis were asked how they got to work and how far. They were not asked what they rode. The £4,000 carbon road bike and the £150 hybrid off Facebook Marketplace sat in the same column of the same spreadsheet, and the 41% is the average of both.

The 30,640 Danes in Copenhagen ticked a box that said they cycled to work. The 300,000 people in the census study wrote "bicycle" in the box marked "how do you usually travel to work". The 125 cyclists in Birmingham were screened on what they could do, not what they owned. Nobody recorded a groupset. Nobody weighed a frame. The 52,513 Danes in the diabetes study reported minutes per week. The 26,000 commuters in the wellbeing study were asked how they travelled, not what badge was on the down tube.

Every single one of these findings is about riding. Not one of them is about bicycles as objects. The effect is in the doing.

Which means the forty minutes with eleven tabs open is not preparation. It's the opposite of preparation. It is the single most effective way yet devised of not going for a bike ride.

"But surely an e-bike doesn't count"

Somebody always says it, usually with a slight smile, and it deserves a proper answer rather than a defensive one.

The PASTA project (Physical Activity through Sustainable Transport Approaches) surveyed more than 10,000 people across seven European cities: Antwerp, Barcelona, London, Örebro, Rome, Vienna and Zurich. Castro and colleagues published the e-bike analysis in 2019. It measured physical activity in MET-minutes a week, which is the standard way of counting exercise while accounting for how hard it is.

E-bike riders: 4,463 MET-minutes a week. Conventional cyclists: 4,085.

The e-bikers were level with the cyclists, if anything slightly ahead. Not because pedalling with a motor is harder (obviously it isn't) but because they rode further and more often. Their average trip was 9.4 km against the conventional cyclists' 4.8 km, and their daily distance 8.0 km against 5.3 km. Less effort per kilometre, considerably more kilometres, and it balances out.

The Reading study above found the same thing from a different angle. Its e-bike group improved on executive function just like the pedal cyclists, and also improved on processing speed and on a standard mental-health score compared with the non-cycling controls. The researchers' own reading was that it isn't only the exertion doing the work: getting out, being independent, going somewhere under your own steam matters too.

The motor doesn't remove the exercise. It removes the excuse. It flattens the hill you've been using as a reason, and it means you arrive at the meeting looking like a person rather than a crime scene.

"But isn't cycling dangerous?"

This is the other objection, and it's a fair one, so here is the study that set out to answer it directly.

De Hartog and colleagues, Environmental Health Perspectives, 2010, modelled what would happen if 500,000 people in the Netherlands aged 18 to 64 switched their short daily car trips (7.5 km, about half an hour) to a bicycle. They counted everything against cycling: more air pollution breathed in, because you're breathing harder; more traffic accidents, because you're more exposed.

The result, per person: 3 to 14 months of life gained from the extra physical activity, against 0.8 to 40 days lost to inhaled pollution and 5 to 9 days lost to accidents. Benefits roughly nine times larger than the risks. The authors' phrase was that the benefits outweigh the risks "by an order of magnitude". That was in the Netherlands, where the roads are kinder than ours. The gap narrows in Britain. It does not close.

What this evidence can't tell you

I'd rather say this myself than have you find it out later.

Almost all of these are observational studies. They watch what people already do; they don't assign anyone a bicycle and a control group. (The Reading study is the exception, and it's the smallest.) The BMJ authors put it plainly in their own limitations section: "As is the case for any observational study, residual confounding is always possible and associations may not imply causation." Their conclusion is carefully worded too: "the findings, if causal…"

There's an obvious objection lurking in that. People who cycle to work might already be healthier, richer, thinner and less likely to smoke, and it might be the health causing the cycling rather than the other way round. The researchers adjusted for a long list of those things (age, sex, deprivation, diet, smoking, alcohol, BMI, other physical activity) and the association survived. The Copenhagen study adjusted for leisure-time exercise specifically and the effect still held. But adjustment is never perfect and honest scientists say so.

What I'd say is this. Six independent research groups, using different methods on different populations in different countries for different purposes, over thirty years, all found the same direction of travel. That's not proof. It is about as strong a hint as this kind of research produces, and it points the same way as common sense: moving your body outdoors most days is good for you.

And none of the objections touch the point I'm actually making. Even if you think the effect sizes are generous, the studies still didn't ask what bike anyone rode. The uncertainty is about how much good it does. It was never about which bicycle.

So: any bike will do

I write about beautiful bicycles for a living. I've spent this year on belt drives, on whether small wheels are slower, on cities that turned a dead river into a nine-kilometre cycle route. I love the objects. I am not about to pretend otherwise.

But I've also watched enough people talk themselves out of cycling to know what the real obstacle is, and it is almost never the bike. It's the belief that there's a right bike, and that riding the wrong one is a bit embarrassing, and that it's better to wait until you can do it properly.

There is no properly. There's a spreadsheet where a road bike and a shopper sit in the same column, and the people in that column outlived the ones who drove.

So here is the whole method, for the bike that's already in the shed:

1. Pump the tyres up. Most neglected bikes are running at half pressure, which is why they feel like riding through treacle. The number is printed on the tyre wall. Any pump will do, too.
2. Raise the saddle. Sit on it, put your heel on the pedal at the bottom of the stroke, and your leg should be almost straight. Nearly everyone rides too low.
3. Squeeze the brakes. If the lever reaches the bar, ask a bike shop to adjust them. It's a ten-minute job and they'll do it while you wait.
4. Ride it to the shop. Not to work, not yet. To the shop, for milk. That's the first trip. The second one is easier.

Road bike, folder, cargo bike, e-bike, mountain bike with slick tyres on it, the hybrid that's been in the shed since 2019: the research doesn't care, and neither do I.

Just ride the thing.

Two things that fit whatever you own

This month's mug says the same thing with fewer footnotes. It's a full wrap of illustrated bicycles (roadster, folder, hybrid, hardtail, road bike, tandem, cargo trike, kid's bike, step-through) every one drawn at the same size, none of them the hero. £18, September only, then it retires to the Velorution Vault.

Get the Any Bike Will Do mug — £18 →

And if you want one thing that improves any bicycle you already own, it's a helmet you don't mind wearing. Dashel make theirs in Britain, they're slim enough not to look like safety equipment, and they fit a Brompton and a road bike equally badly, which is to say equally well.

See the Dashel ReCycle helmet — £79 →

Sources

• Celis-Morales CA, Lyall DM, Welsh P, et al. "Association between active commuting and incident cardiovascular disease, cancer, and mortality: prospective cohort study." BMJ 2017;357:j1456. 263,450 UK Biobank participants, 22 assessment centres, median 5.0 years follow-up. All hazard ratios quoted are the maximally adjusted models.
• Andersen LB, Schnohr P, Schroll M, Hein HO. "All-cause mortality associated with physical activity during leisure time, work, sports, and cycling to work." Archives of Internal Medicine 2000;160:1621–1628. 30,640 Copenhagen residents aged 20–93, mean 14.5 years follow-up.
• Patterson R, Panter J, Vamos EP, Cummins S, Millett C, Laverty AA. "Associations between commute mode and cardiovascular disease, cancer, and all-cause mortality, and cancer incidence, using linked Census data over 25 years in England and Wales: a cohort study." The Lancet Planetary Health 2020;4:e186–e194. 300,000+ commuters, 1991–2016.
• Duggal NA, Pollock RD, Lazarus NR, Harridge S, Lord JM. "Major features of immunesenescence, including reduced thymic output, are ameliorated by high levels of physical activity in adulthood." Aging Cell 2018;17:e12750. 125 cyclists aged 55–79, 75 inactive older adults, 55 young adults.
• Leyland L-A, Spencer B, Beale N, Jones T, van Reekum CM. "The effect of cycling on cognitive function and well-being in older adults." PLOS ONE 2019;14(2):e0211779. 100 adults aged 50–83, eight-week intervention, pedal cycle, e-bike and control groups.
• Rasmussen MG, Grøntved A, Blond K, et al. "Associations between recreational and commuter cycling, changes in cycling, and type 2 diabetes risk: a cohort study of Danish men and women." PLOS Medicine 2016;13(7):e1002076. 52,513 adults aged 50–65, mean 14.2 years follow-up.
• Clark B, Chatterjee K, Martin A, Davis A. "How commuting affects subjective wellbeing." Transportation 2020;47:2777–2805, and the UWE Bristol summary of the Commuting and Wellbeing study. More than 26,000 workers in England over five years, Understanding Society data.
• Castro A, Gaupp-Berghausen M, Dons E, et al. "Physical activity of electric bicycle users compared to conventional bicycle users and non-cyclists: insights based on health and transport data from an online survey in seven European cities." Transportation Research Interdisciplinary Perspectives 2019;1:100017. PASTA project, 10,000+ participants.
• De Hartog JJ, Boogaard H, Nijland H, Hoek G. "Do the health benefits of cycling outweigh the risks?" Environmental Health Perspectives 2010;118(8):1109–1116. Modelled shift from car to bicycle for short trips, 500,000 Dutch adults aged 18–64.