Cycling is good for you. This much is obvious. But what might be some of the lesser known benefits?

Here's a fascinating study (that I discovered through Lloyd Alter's blog), which looked at the association between active travel modes and brain health — specifically dementia risk. For this study, the researchers analyzed nearly 500,000 people in the UK and then tracked them for a median period of 13.1 years. How people got around was classified according to the following groups: non-active (like driving or taking public transit), walking only, mixed-walking, and cycling and mixed-cycling. This latter category is meant to capture people who cycle exclusively and who mix it with other forms of mobility.

Based on this, the researchers uncovered these cycling benefits compared to non-active travel:

• 19% reduction in all-cause dementia

• 22% reduction in Alzheimer's disease

• 40% reduction in young-onset dementia

• 17% reduction in late-onset dementia

Cycling was by far the best performing category. Why is that? Well, exercise in general is good for brain health. It increases blood flow and oxygenation to the brain, decreases cortisol levels (stress hormone), and reduces anxiety and depression, among many other beneficial things. But perhaps the most important feature for this particular discussion is that it's simultaneously a physical and cognitive activity. In other words, it's exercise, but your brain also has to do a lot of other stuff like balance the bike, avoid obstacles (such as car doors being flung open), and generally navigate an environment with many stimuli.

This gives new meaning to

Yesterday morning I went cycling in High Park to try and condition myself for the Bike for Brain Health ride that I have coming up. The Park is such an incredible amenity and I love being so close to it. Of course, before I set out, I turned on my Apple Watch and Garmin computer so that I could track it all in Strava. This has become such a big part of cycling (and working out in general). We're all data obsessed. Everyone wants to track their route, their speed, their heart rate, and whatever else.

The result is that Strava collects mountains of data about the way people actively move about in cities — data on everything from cycling to backcountry skiing. Some of this aggregated/anonymized data is available to the public via their global heatmap, but much more of it is available to urban planners and active transportation groups around the world. In fact, this is part of what Strava does: they help city builders. Here are some urban case studies spanning Rio de Janeiro to Park City.

Looking at central Toronto, our heatmap looks like this: