We all know that kayaking is a healthy pastime. It’s aerobic, easy on joints because it’s non-weight-bearing, and it gets you out to where all the fresh air is. Sure it’s a little expensive once you’re hooked, but much cheaper than cycling and you’re less likely to be run over by a bus.
So how does kayaking compare to other sports?
There was an article published recently on livestrong.com that got a lot of people talking. It discussed how many calories are burned when kayaking, which depends on your body weight. It usefully determined that a 80kg paddler would have to paddle for 18 hours to burn a kilogram of fat. Then it went on to compare kayaking to a number of other activities. Kayaking was a little easier than running, and a little harder than cycling. An hour of kayaking was equivalent to an hour of playing softball. Now at that point, I was thinking “Seriously?” Softball players spend 90% of their time standing around waiting to hit the ball, throw the ball or catch the ball, interspersed with a few 100 metre runs, if they’re lucky. That just can’t be right.
There has to be more to it. And there is.
To come up with a meaningful comparison, you need to factor in more than just “kayaking”. The biggest factor to consider is obviously how fast you paddle. The faster you paddle, the harder your body works, and the more energy you burn. Weight is also a factor since when you paddle, you’re pulling your body through the water against the forces of friction. The heavier you are, the deeper the boat sits in the water, and that means that more of the hulls surface area is in contact with the water that’s trying to slow you down. Then factor in the fact that different boats are more or less efficient through the water and differences in technique will move some paddlers faster for less effort than some other paddlers. Add in musculature, level of fitness and a myriad of other factors and “voila!” you have an answer.
In short, it’s complicated
So it’s lucky for us that Contance Mier PhD has already worked it out for us using a set of data known as “The Compendium of Physical Activities”.
Over a couple of decades, some serious boffins have measured and recorded the energy expenditure of many many activities including kayaking and canoeing. They’ve also measured runners, joggers, swimmers, brick layers, and alter boys which provide some interesting comparisons. To make the data meaningful, they’ve recorded them as multiples of how much energy a person burns while they’re lying around doing nothing.
There are some calculators available on-line to do the calculations, but that’s probably because the calculations are based metric and Americans are completely flummoxed by metrics and needing to multiply everything by 2.2.
For those us who live in metric countries, you simply take your weight in kilograms, and that’s how many calories you’d burn each hour if you were lying down. Every activity in the compendium is then a multiple of your lying down number.
So my weight in KG is 79. That means I consume 79 calories per hour when I’m doing nothing. This is called the Basal Metabolic Rate [BMR]. Multiplied over 24 hours, that’s 1896 calories a day before I’ve even put my socks on.
Each activity listed in the compendium has a number associated with it. If you multiply your BMR by the number for an activity, that’s how many calories you’ll burn if you perform that activity for an hour. For extra credit, you can break your day into lots of activities and convince yourself that you really have earned that ice cream. But I’ll stick to paddling.
The compendium lists a range of different MET numbers for various levels of canoeing intensity from 3.0 for light effort to 12.0 for racing. Yes, I know it’s canoeing and you’re all kayakers, but there’s other research that shows the two activities are generally equivalent. The index provides some indicative speeds for the different intensity levels.
|Canoeing Activity||Speed||MET index|
At this point I’ll pour in a little pseudoscience and say that I equate these intensity levels to heart rate zones when I’m trying to determine how many calories I’m burning. I do this because I think it’s more about the intensity you are exercising at than a nominal speed which is usually a combination of boat design, tides, currents, and other factors.
So going back to my example… I’m training hard over three hours, which is approximately what it takes me to cover the 30km loop from Woronora to the Holsworthy amphibious boat dock, I spend most of that three hours above 80% of my max heart rate, so I’d call it vigorous. The MET index for “vigorous” canoeing is 12.0. Multiply that by my BMR of 79 and I get 948 calories per hour. Multiply it again by three hours and I find that my hard 30km training paddle burns 2844 calories, which is a pretty good workout for three hours.
A kilogram of fat is approximately 7700 calories so if I paddle hard for three hours I should burn off the equivalent of 360 grams of body fat. More realistically, I need to put 2800 calories back into my body to replace the 2800 I’ve used or I’m in energy deficit.
If you want to compare paddling to other activities, you can select your level of paddling effort from the table above and see how it compares to the activities in the Compendium. I’ve pulled out a few selected ones as examples.
|Other Activity||Speed||MET index|
|Cycle Racing||25-30 kph||12.0|
|Cycle Racing||>30 kph||16.0|
|Stationary Bike||250 watts||12.0|
|Rowing Machine||200 watts|
|Vacuuming the house||3.5|
|Carrying groceries upstairs||7.5|
|Walking the dog||4.0|
|Playing the Cello||2.0|
|Digging a ditch||8.5|
|Swimming Freestyle Fast||10.0|
And while you may have heard that a furtive romp with you partner is as good as a 5 mile run… Not according to the scientists. It only rates a 1.5, which is on a par with knitting a scarf. A very short scarf. The full data table makes fascinating reading.
So the big question… what does all this mean for me?
Well if you’re looking to compare the exercise benefits of kayaking with other sports because fresh air and low impact aren’t good enough reasons, you now have a handy dandy list of how various activities compare.
If you’re looking to understand how many hours of kayaking you have to do to lose a few pounds (we’ve already agreed that kayaking is a superior exercise to every other activity in all respects) you can do a little simple maths and see how many hours you need to paddle to lose those pounds (if you don’t want to do the maths, an 80kg paddler will burn a kilogram of fat for every 14 hours of moderate paddling)
Personally my interest started with trying to work out how much food I need to consume to stay fueled during the Hawkesbury Classic. This approach lets me work out how many calories I need to replace if I’m racing hard over 10 hours – a staggering 7900 calories. I’m even more interested to understand how much fuel I need to do that continuously over the five days of the Murray Marathon. I haven’t got there yet, but it’s fair to say that it’s a staggering amount of food. My next problem is that your muscles can consume glycogen, which is what becomes of carbohydrates, fats and proteins aka food, about 3 times faster than you can replace it by eating. That’s before I get to the subject of what sort of food (carbs, fats, proteins) I should consume before, during, and after the race.
But that’s a discussion for another day.
The full spiel on how to calculate energy consumption while kayaking – http://files.meetup.com/268859/Calories_burned_while_kayaking.pdf
The Compendium of Physical Activities – http://prevention.sph.sc.edu/tools/docs/documents_compendium.pdf
The original article on LiveStrong.com – http://www.livestrong.com/article/306460-calories-burned-per-hour-of-kayaking/
disclaimer. I’m not a doctor and this is not a substitute for a medical opinion. This article is based on my understanding of the articles referenced above.