As I pull my kid around in his bike trailer, other cyclists pass me as though I am stopped on the side of the road changing a flat. I console myself by counting trailer miles twice.

Ten miles pulling the trailer should go in the log book as 20 miles, right? That’s my rule of thumb. Calories burned per mile? Double that, too!

The truth ain’t that far off, the math is fairly simple, the variables, however, make this a matter best left for scientists and philosophers.

### Calories Burned While Cycling

Speed and weight determine calories burned:

- 15 mph = 0.049 calories per pound per minute
- 25 mph = 0.139 calories per pound per minute

Calories burned per pound per mile ridden is not a linear function — going from 15 miles an hour to 30 miles an hour doesn’t double your calories burned. Drag is proportional to the square of speed. Thus overcoming drag at higher speeds results in far more calories being burned. Just trust me when I say Aerodynamic drag is complicated and let’s do some examples

### Cyclist at 130 Pounds

- 15 mph = 0.049 calories * 130 pounds = 6.37 calories per minute
- 15 mph = 25 calories per mile
- 25 mph = 0.139 calories * 130 pounds = 18.07 calories per minute
- 25 mph = 43 calories per mile

### Cyclist at 180 Pounds

- 15 mph = 0.049 calories * 180 pounds = 8.82 calories per minute
- 15 mph = 35 calories per mile
- 25 mph = 0.139 calories * 180 pounds = 25.02 calories per minute
- 25 mph = 60 calories per mile

### Cyclist at 220 Pounds (ie: me)

- 15 mph = 0.049 calories * 220 pounds = 10.78 calories per minute
- 15 mph = 43 calories per mile
- 25 mph = 0.139 calories * 220 pounds = 30.58 calories per minute
- 25 mph = 73 calories per mile

### Calories Burned While Pulling a Trailer

My nearly four-year-old son clocks in at 45 pounds. His trailer weighs about 30 pounds. He has another ten pounds of toys, snacks and drinks. That means I’m hauling around 85 more pounds.

Since I’m positive I’m not going 25 miles an hour while pulling the bike trailer, let’s isolate just that 85 pound load at 15 miles an hour…

- 15 mph = 0.049 calories * 85 pounds = 4.165 more calories per minute
- 15 mph = 17 more calories per mile

That means it takes 40% more energy to pull the trailer than to just drive myself around, all else being equal.

As a 220-pound cyclist, it costs me 43 calories per mile to ride. Toss the trailer on there and I’m burning roughly (very roughly) 60 calories per mile.

For a lighter biker, the trailer is a larger percentage of the total weight involved in the trip. As such, the lighter the rider, the more meaningful the increase in calories burned while pulling the trailer.

### Why This Calculation Isn’t Right

The above calculations don’t consider the shape of the trailer. All they are doing is making the cyclist fatter. I’m sure even a fat biker is more aerodynamic than a box-like trailer. These calculations also don’t consider that there are two more tires in the mix affecting both friction on the road and the tires’ rotational momentum. Add in a head wind or tail wind and you’d have to recalculate. These numbers also only apply to flat rides. Add in some hills and you’re on your own.

### My Bike Gets 517 Miles Per Gallon

A gallon of gas has 31,000 calories of energy, give or take.

To figure out how many miles per gallon you get on your bike, first figure out how many calories you are burning on your bike. Then, take that number and divide it into 31,000.

As I noted above, I burn 60 calories a mile when pulling the trailer. 31,000 divided by 60 is about 517 miles per gallon. Keep that in mind the next time that coworker talks about his Toyota Prius.

### Just Double Up and Call It a Day

At the end of the day, I just call it double. Pulling a trailer is simply double the effort of not pulling a trailer. It takes twice as long to get out the door with a kid and trailer. It takes twice as long to get anywhere. I have to pay double the attention to traffic and the road itself. There are twice as many potty stops.

Fortunately, riding with the kid in the trailer makes me feel twice as good so it all averages out in the end.

—Matt

I pull my 2 and 4 year olds in the Burley. Together, they are 80 lbs. Plus the trailer. If I bike 8 miles, which is the distance to the pool and back, how many calories are burned?

In order to answer your question, I’ll need to know how much you weigh and how fast (mph) you are riding for those eight miles.

Cheers,

Matt

ooh, can you do me? :) 10 mph avg, trailer + 2 kids + stuff = about 85 lbs, I weigh 143 currently.

Thanks!

:) Christina

Double it and call it a day :) Enjoy the fact that you’re working harder than anyone else out there! (Except for all the math!)

Monitoring Calories Burned during your workout routine could be really helpful in keeping you motivated. I use this website that tells you how many calories were burned during the exercise you did that day http://www.fitclick.com/how_many_calories_burned

Thank you for the impressive post about burning calories while cycling. Your post delivered a bunch of fascinating points that I have not considered. I am looking forward to reading more of your website in the future.

every morning I start my long haul to take the kid to daycare and then off to work I go, 10 miles round trip one way. I get some funny looks and some comments of “love the trailer” or “he seems to be having to much fun” Over all the kid loves it!

This was very helpful! I was trying to figure this out as well. We have a trailer but since my

Two year old can’t leave his 1 year old brother alone, I am getting a seat for the little one and putting that on the back of my bike and the big one can ride alone in the trailer. :-) i just calculated it as a vigorous ride vs a “light” or “moderate” exercise!

Can you do the math for me? Kids weigh 60 lbs before Burley weight. I am 120 lbs biking at normal get there pace 4miles to swim lessons. Thanks

What if you pull 3 kids? 50 lbs of kids in a trailer, and 35 lbs on a bike seat? 10 lbs of bike seat, 25 lbs of trailer, 5 lbs of supplies=125 lbs load. I am just trying to calculate it for my running XT calculations.

I weigh 150 on a speed bike on the highest setting pulling three toddlers each 34 pounds and a home made trailer that’s 50 pounds. How many calories am I burning??