How getting rid of my car made me an Ironman

Had I driven to work everyday for a year, I would have spent 154 hours driving a car. Aint nobody got time for that. In training for Ironman Boulder, I trained for 421 hours over a seven month period. The time would equal almost a third of the training required for an ironman event. What if you could bike everywhere instead of drive?


If you want to replicate my results in your training, a few things to keep in mind:

  1. At 24 miles round-trip, my work commute may have been longer than average, and allowed for mostly uninterrupted riding.
  2. I had convenient swim training locations which did not involve any out-of-the-way travel.
  3. I’m much stronger at cycling than running or swimming, but others may need to run or swim more than I did. (try running to work!)
  4. Protected bike parking at work allowed me to ride my expensive bike to work without fear of the bike getting stolen. This matters if you want to train more on the bike you will use in the event (somewhat important, but not critical)

What did my regular commute look like?

Boulder is a pretty compact place, often described as “twenty-five square miles surrounded by reality.” Most of my commuting was to work (in Longmont) or around town. Here’s a map to get you a better flavor. Click to zoom:

Boulder bike commuting map via Strava heatmap

How many hours does it take to train for an Ironman?

For the typical person, finishing an ironman triathlon event normally takes thirteen to seventeen hours of endurance exercise, which requires a large amount of training. Athletes often start training six to eight months in advance – I started in January in preparation for Ironman Boulder on August 2nd. Here’s a monthly summary from my training plan which averages about fourteen hours a week and peaks at almost eighteen hours a week:

Ironman training time

How much money does an ironman event cost?

Explicitly, an ironman event is rather expensive — mine was $685 just for registration, and many people also must pay for travel and lodging. Gear expenses likely exceed $200-400 for running shoes, wetsuit rental or other gear, assuming you don’t need to buy a bike.

But food expense may be the most ignored cost. An athlete training ten hours a week should expect to burn 30-50% more calories than a sedentary person. At an additional $20-40 per week, the total cost would be $520 to $1040 over a six-month training period.

How much time might I’ve driven if I didn’t bike commute?

Since I did not use a car for commuting, I needed to calculate how much time I would have spent in a car had I driven. Based on my biking data, I calculated that my average speed when commuting was 14.9 miles per hour, while if I drove, I estimate my average speed would have been 29 miles per hour (approximately half city and half highway driving, including stops).

CodeCogsEqn (5)

Using the bike/car time ratio and multiplying through by the number of hours I biked, the calculation for substituted driving equates to:

  • 4.2 hours per week of replaced car commuting, or
  • 125.7 hours of replaced car commuting during the 7-month period.

Since my total training time over this period was 421 hours, spending 125 hours in a car would have reduced my potential training time by 30% without spending additional time.

The opportunity cost of time – number of hours in a day

The main obstacle an ironman athlete faces is fitting in the required training into the typical 24-hour day. After subtracting eight hours a day for sleep (it’s important!) and six-to-eight hours a day for working (averaged over seven days), and an average of two hours a day for basic errands (eating, cleaning, regular maintenance), the typical athlete has difficulty fitting in two hours a day to train.

Ironman weekly time trade-offs 3

Each hour of driving replaced with bike riding will help reclaim training time. The graph demonstrates two options of how an athlete may spend his or her time, bike commuting or not. Along each curve the athlete can also decide how much free time he or she may use for training. By bike commuting, a person training for an ironman has better options: more potential training time, more potential free time, or anywhere along that curve.

The opportunity cost of money – driving vs. biking

Bike commuting instead of driving has great advantages in the time-cost of driving, but what about the monetary cost of driving? Since I’ve calculated the total commuting miles during the seven-month period at 3,646 miles, multiplying this by the 2015 Federal reimbursement rate of 57.5 cents per mile equals a gross savings of $2,096 over a seven month period.

The net savings will be lower than the gross savings after subtracting the cost of biking instead. But you were going to bike that much anyway, right? In which case, the gross savings completely covered my entry into the Ironman event and additional food cost used in training.

Completing an ironman without giving up too much

Completing an ironman event often requires more than a casual commitment of time, money, and lifestyle. Many consider ironman events to be too-consuming: but the key to completing one is optimizing the resources at your disposal.


4 thoughts on “How getting rid of my car made me an Ironman

  1. This is really interesting to see mapped out Eric. I don’t understand how people with full time jobs and families find the time to train for an Ironman, even if they are being smart about integrating training to make up for other parts of the daily routine.

    Will you do it again?

    1. Thanks! I agree, very interesting to me in retrospect as well. I think the rule is: full time job, family, ironman—pick two.

      I went into the event with the intention of only doing one. Still sticking with that plan for now!

      1. That’s a great Q, & since I already have 2 of those 3, I’m not really planning to Iron.
        But I love seeing this mathed out! I should figure out quantitatively how biking benefits my life. Did you start with a Half-Iron?

      2. Thank you. Agreed, a half-ironman takes only 1/4th to 1/2 of the training (in my opinion). This was my a first triathlon (which is another story).

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