“Car commuters find their journey more stressful than other mode users. The main sources of this stress appear to be delays and other road users. Car commuting stress has been found to be associated with increased negative moods on arrival at work and the home, lower tolerance threshold, cognitive impairment, greater illness and work absenteeism, job instability and a negative effect on overall life satisfaction. Driving is also the most stressful mode because drivers must budget a considerable amount of extra time to deal with unexpected delays and are more likely to be stressed when faced with disruptions to their journey. This additional time budget indicates that they have, perhaps paradoxically, less control over their commute than commuters on other modes.”

From The Role of Active Travel in Improving Health by Sustrans UK

Running is the original utilitarian form of urban transport and the advantages that existed for our ancestors are still just as prescient today:

• Running is faster than walking: the average person walks at around 3 mph. If you can maintain 10 min/miles, you’re travelling twice as fast as walking pace. 
• Running is faster than driving: In downtown Manhattan, average driving speeds are around 7 mph. That’s 8:34/mile pace. Bear in mind that New York drivers also spend around two hours per week looking for parking spots, and it’s easy to understand how even an easy run commute followed by a shower and a few minutes waiting in line for a breakfast sandwich can take less time than driving.
• Running works well in combination with biking: bikes are great, but unless your commute is 10 miles or more, it’s unlikely to have much positive impact on your fitness. If anything, biking can make running awkward: ride home, get changed, run, get changed, eat; who has the time? However, biking and running make great bedfellows over shorter distances. Say your commute is eight miles. Ride there on Monday morning with clothes for two days, then run home Monday night. Run to work on Tuesday morning, ride home Tuesday night.
• Runners never get stuck in traffic: when you run, you know within a minute or two when you’re likely to arrive at your destination. There’s no risk of getting caught in traffic, being stuck on a broken down train or getting a flat tire. 
• Running is the perfect socially distant mode of transport: by running rather than taking the bus or the train, you come into close contact with fewer people, and you’re not stuck inside breathing the same air as strangers. 
• Base miles are the best miles: since Arthur Lydiard introduced the idea of long slow miles as the base of running fitness, we’ve come to recognize that the more miles you can run without breaking down, the faster you’ll likely be come race day. The problem for most of us is finding time. Run commuting is the most efficient way to add miles to your weekly total without eating into recovery/family/social time.  
• Running is cheap: compared to the train, or driving and parking, running is cheap. At worst, you have a great excuse to treat yourself to more shoes and a fancy lunch.
• Running has a minimal carbon footprint: assuming you’d have been wearing clothing, breathing, and consuming sustenance, however you chose to get to work, your carbon footprint should be lower through running than any other mode of transportation.
• Running is the best way to learn a city: there’s a lot to be said for passing through a city at a human speed, feeling the changes in the seasons, watching the minutiae of the city change from month to month. New routes, new faces, new oases of calm––it’s all there to be discovered when you travel on foot.
• Commuting gives running a purpose: on days when motivation is missing, the necessity of getting from A to B will get you out the door or get you home.
• Active transport makes you more productive at work: people who get to work by active transport self report that they’re more productive than their co-workers.
• Commuting makes you more resilient: quitting isn’t an option––you have to get home, whether you feel good or not.
• Commuting teaches you to run slow: if you’re carrying a pack, you’re probably not going to be thinking about pace as the primary judge of a run’s quality. If you’re also running doubles, at least occasionally, eventually you’ll find a pace that is slow enough to not detract from your performance-oriented sessions, but fast enough to get you to work on time.

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