Calculating calorie burn for unconventional sport

September 19, 2012 12:43 AM

With all the specifics can I calculate a better estimate of how many calories I burn doing archery than online calculators (that give me figures as low as 220 and as high as 500 calories per hour)

If I know my weight, my draw weight, how many arrows I shot, how far away the target is and how many times I walked there and back can I calculate a fairly accurate figure?

Its mostly for curiousity but also for determining how many extra calories I should consume on training days - I don't want to fall into that trap of overconsuming due to exercise but I also dont want to be undernourished and hurt my performance/progress

posted by missmagenta to Health & Fitness (10 answers total)

Different online calculators will have different baseline assumptions about BMR, heart rate, etc.

The best, most accurate way is to use an on-body heart-rate monitor (with chest strap), possibly one with GPS capability. I remember reading an article recently that talked about the different algorithms and assumptions that go into the various models and how they calculated activities differently.

I personally have never counted specific exercises as contributing to my daily caloric expenditure other than rough estimate (sedentary / light activity / moderate activity ) multipliers.

The way I usually see people do this is to continue with whatever plan they have been on, not taking into account energy expenditure due to exercise, and then tweaking their diets if and when performance issues due to fatigue / fuel inadequacy develops.
posted by the man of twists and turns at 1:07 AM on September 19, 2012

Response by poster: According to my heart rate monitor (and online calculators that use average heart rate instead of activity), I burn 500 calories per hour just watching TV, which is obviously not true, not even in the ballpark. According to my fitbit (which only measures movement) I burn around 100 calories per hour when sedentary which is much closer to the truth. I used to have a fancy polar one with a chest strap but it didn't work, it stopped tracking heart rate whenever I moved so I stopped using it. Unless anyone has a recommendation for a chest strap suitable for the busty girl?
posted by missmagenta at 1:53 AM on September 19, 2012

My guess (as someone who does a fair bit of archery) is that the activity doesn't consume much more energy than standing up and walking around does by itself. Part of the problem of using heart rate as a tool is that, in archery, there's a lot of emphasis on relaxing, breathing correctly and being very steady and consistent in the few seconds that you're actually drawing and shooting. Your heart rate is probably going to be higher when you're walking up and down than it is when you're actually executing a shot. Treating the activity as 'standing around a lot with the occasional brief bit of walking' should be a fair guide.

I personally wouldn't make any changes to my overall diet beyond perhaps keeping a few healthy snacks available in case of hunger during training. I spent four hours practicing on Friday and the level of activity felt about the same as taking my kids to the park; I wouldn't adapt my diet for that.

Simon S. Needham, the author of 'Archery - The Art of Repetition', is as good an authority as anyone, and at the end of a token chapter on nutrition, he mentions that he takes jam (that's jelly if you're American) sandwiches along to competitions.
posted by pipeski at 2:16 AM on September 19, 2012 [2 favorites]

I don't think this isn't really something where you'll get very far by calculating how much you should eat from someone's model, but if you were going to I'd start by thinking of drawing your bow as being like an upright row with a lot of repetitions and look on body building forums for advice.
posted by Blasdelb at 2:30 AM on September 19, 2012

Did you try moistening the heart rate monitor band before you put it on? Usually busty shouldn't matter (band goes underneath your bust, under your bra band), but they need something conductive to maintain contact when you're moving. For most people that's sweat, but if you're not going to sweat then you should put a little water, a swipe of specialty conductive gel, or a swipe of pure aloe gel on the conductive pads before you put it on.

But beyond that, agreeing with the above that I wouldn't really modify what I eat for archery. What I probably would do is modify when I eat it, allowing myself a snack and taking a little out of my other meals to compensate. I usually need my snack some time before exercise, but you might prefer during or after, it's completely a case of do whatever feels best.
posted by anaelith at 3:50 AM on September 19, 2012 [1 favorite]

I run, and sweat a *lot*, but my HRM loses the memo if I don't soak the electrodes before putting it on. Just FYI.
posted by notsnot at 5:08 AM on September 19, 2012

Response by poster: As I said, this is mostly curiosity, however to add a little context I'm currently on a 1600-1800 calorie per day deficit (with doctor approval), excluding any extra from exercise so I'm trying to find a good balance between sticking to that and having the stamina to keep my performance up throughout the whole session
posted by missmagenta at 5:17 AM on September 19, 2012

The forums over at myfitnesspal have some good posts on using HRMs and most importantly -- calibrating them (there is also a lot of cruft over there, and a few very expert posts). And if you are calorie counting, it is also the best tool I have found.
posted by Tallguy at 6:50 AM on September 19, 2012

I'd retry the HRM, because everyone is so individual - heck, just walking to and from the target burns a lot more energy if you're 300 pounds than it does if you're 150 pounds. I'm busty and my polar HRM works pretty well (not perfectly, but quite well) as long as the electrode thingy is damp - which it'd be much less likely to be if you're sedentary. With your current focus on a narrow band of calorie deficit, it makes sense to try it to get a better sense for your numbers.

Archery sounds fun! The rule from my (very good) fitness instructor is 15-30g of carbs within a half hour before starting your workout. This translates to something like half a banana. More importantly, he insists on a post-workout snack within a half hour after, with the gold standard being chocolate milk for its proteins and sugars. He says that research pretty strongly shows that that the post workout snack is what helps your body get out of the catabolic state and back to a better ability to rebuild muscle and stamina, etc.

So! You shouldn't need a lot more calories (those two snacks add ~250 calories), but start with something like those snacks, and see how it works for you. I, after years of working out first thing in the morning (ie, fasting), found I could work out a lot harder and more efficiently with that half a banana to get my muscle glycogen back up. And the chocolate milk after a hard workout tastes Amazing. Go you for working on this stuff!
posted by ldthomps at 7:49 AM on September 19, 2012 [1 favorite]

I'd go with whatever the FitBit is telling you. The major calorie consumer during an activity like archery is going to be standing up and moving around. I doubt -- although it may feel like a lot of work -- that the actual act of raising and drawing the bow is going to burn a significant number of calories. So the FitBit, by measuring steps and gross movement, is probably giving you a reasonable value.

FitBit has some 'activities' like "Walking around carrying things" that might be appropriate to use when logging your practices; I suspect that they have slightly higher calorie burn rates associated with them, but shouldn't grossly overestimate. That might be worth using.

I'm not really sure why your HRM is overestimating so badly... but heart rate based calorie consumption estimates are based on a lot of standard assumptions. Basically, it's trying to give you one figure (energy consumption) by measuring something totally different (heart rate), and to get from one to the other it's assuming a lot about your body (in particular, cardiac efficiency). Most tools don't let you do much to adjust the model, so they work fine for some people but are hilariously off for others.

Although sanity-checking it against resting heart rate is a great idea; if something claims that your BMR is 12,000 calories/day, chances are it's not really good.
posted by Kadin2048 at 9:03 AM on September 19, 2012 [1 favorite]