tag:blogger.com,1999:blog-8190463771981947702.comments2024-02-03T00:19:16.587-08:00Hiking ScienceZéhttp://www.blogger.com/profile/05586616856287881679noreply@blogger.comBlogger197125tag:blogger.com,1999:blog-8190463771981947702.post-10002142676758699542017-07-26T13:13:44.227-07:002017-07-26T13:13:44.227-07:00Thank you for such an intelligent read and smart l...Thank you for such an intelligent read and smart little calculator!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-60232481513019359882017-06-20T02:59:08.043-07:002017-06-20T02:59:08.043-07:00Both walking and running are so very inefficient a...Both walking and running are so very inefficient as means of moving the human body forward that you can't readily assume basic physics will give you the correct answer. Take running. Try running on the spot. Notice that you are not moving forward but you are expending a lot of energy. That's because you are bouncing up and down, lifting your entire body up a couple of inches and then letting it fall. You are also lifting your chunky legs up and down. So there you are, running on the spot and not going anywhere - but still getting very out of breath. Cycling is far more efficient at using the human body to make forward motion - have a look at how many calories you burn moving on an exercise bike for 10km compared to using a treadmill. Even with cycling you are using a lot of energy just moving your legs up and down (and spinning the front wheel). You could create a bio-mechanical model for walking or running to gauge the efficiency in different situations, but probably measuring some typical cases is best. Philhttps://www.blogger.com/profile/00757089303866430723noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-81044230628649907592017-06-19T11:37:50.054-07:002017-06-19T11:37:50.054-07:00Wow, Anthony Liberator is a complete idiot.Wow, Anthony Liberator is a complete idiot.Lylehttps://www.blogger.com/profile/12060057999571303817noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-65634496141315612892017-02-24T22:55:33.756-08:002017-02-24T22:55:33.756-08:00Good lord. You try to put out a basic gratis calo...Good lord. You try to put out a basic gratis calorie evaluator and you get endless second guessing and a gazillion other critiques. Not to engage in logical fallacies, but how many of these folks are talking their free time to put together a site like this. Seriously?Anonymoushttps://www.blogger.com/profile/12237582472151356547noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-30016879865193309382016-11-22T08:55:30.068-08:002016-11-22T08:55:30.068-08:00You need to add up the uphill and downhill togethe...You need to add up the uphill and downhill together...Zéhttps://www.blogger.com/profile/05586616856287881679noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-2127725956343967542016-11-22T06:11:26.948-08:002016-11-22T06:11:26.948-08:00This is fucking retardedly off. I hiked 9 miles wi...This is fucking retardedly off. I hiked 9 miles with 75lb pack and you're telling me I burned 600 calories?! <br /><br />I would burn 100 cals per mile just walking with NO backpack. Thats 900 cals WITHOUT my 75lb pack. <br /><br />Who made this? <br /><br />A woman, mid-donkey show, could have made a better calorie burning calculator.ny31gphttps://www.blogger.com/profile/10699004306417404988noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-401117812532493632016-08-30T18:29:12.803-07:002016-08-30T18:29:12.803-07:00Does elevation have any bearing, meaning if my hik...Does elevation have any bearing, meaning if my hike is 4000 or above, my heart seems to be working a bit harder. Anonymoushttps://www.blogger.com/profile/14656088101606607309noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-59347735934386723262016-08-24T11:01:37.640-07:002016-08-24T11:01:37.640-07:00Hello, I so totally agree! Especially walking down...Hello, I so totally agree! Especially walking down I have the feeling it has a huge impact...elahttps://www.blogger.com/profile/11960063333824122088noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-64544129758897132362016-07-16T10:03:17.723-07:002016-07-16T10:03:17.723-07:00Thanks for this page! One question - I entered nin...Thanks for this page! One question - I entered nine miles round trip, but the results say uphill 9 miles and downhill 9 miles. Shouldn't it be 4.5 miles for each?Alicenoreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-60436661925307116372016-07-11T10:01:48.126-07:002016-07-11T10:01:48.126-07:00You are right it does not account for terrain. I h...You are right it does not account for terrain. I have much personal experience with what you described! I originally added a scaling factor for terrain, but I simply don't have the empirical data to support what coefficients to attribute to different terrains. Zéhttps://www.blogger.com/profile/05586616856287881679noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-60437355430320343772016-07-10T16:01:22.297-07:002016-07-10T16:01:22.297-07:00I like this calculator. It's a good incentive...I like this calculator. It's a good incentive for my wife and I to get out walking. Despite the physics I have my doubts about the accuracy however. I walked the CMD Arete route up Ben Nevis back in May. Ice axe crampons. the works. I was shattered when I finished took me 8.5 hours of constant hard graft to reach the summit and 3 hours to trek back down. total route is 11 miles and 1700m of climbing. A few weeks back I walked 22 miles on Dartmoor and did 1050m of accents. That walk was a doddle in comparison. Only took 8.5 hours in total. Yet the calculator says I burned far more calories on that walk. Trust me I burned far more on Ben Nevis. I would assume it's the terrain that made the difference, so would suggest that is a big factor in this calculation.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-65632558514459009152016-06-17T09:43:33.888-07:002016-06-17T09:43:33.888-07:00I think every intelligent commenter on here agrees...I think every intelligent commenter on here agrees on two basic points:<br />1) the base physics are straightforward. F=mass x acceleration, W=mass x distance, etc.<br />2) the difficult part of estimating caloric expenditure has to do with human biomechanics and how all the different factors play into overall process(muscle mass and composition, VO2max, age, weight, sex, height, speed, slope, what I ate for breakfast this morning, etc. etc.).<br /><br />For everyone else who can't get beyond concept of treating this an idealized mass moving in an over-simplified Newtonian physics class exercise, try to imagine the human body as simply an engine with an efficiency curve that relates power output/power input<br /><br />ps - also an engineer ;)Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-27479907993940735022016-01-11T15:51:23.484-08:002016-01-11T15:51:23.484-08:00If you type in 900, it is assuming round trip mile...If you type in 900, it is assuming round trip mileage. If you then only look at the uphill data, that is basically for 450 miles. Zéhttps://www.blogger.com/profile/05586616856287881679noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-24345282294945416592016-01-10T22:07:57.345-08:002016-01-10T22:07:57.345-08:00So i only need to eat 13 3000 calorie meals to wal...So i only need to eat 13 3000 calorie meals to walk 900 miles mostly uphill (aka barefooting the mountains of norway) at ~2mph... This is vastly less than i thought would be neededAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-44366208041917240622015-11-13T15:14:30.464-08:002015-11-13T15:14:30.464-08:00Anthony, are you a Bioengineer perchance? Human be...Anthony, are you a Bioengineer perchance? Human beings work off chemical energy, we're not an internal combustion engine. Energy expenditure still obeys the laws of physics, but there are more factors involved than the way you make it seem. Grand scheme of things, energy is conserved and it may seem intuitive to think of it simply as energy out regardless of HOW the work is done... but that's not a real life scenario. <br /><br />The same way a car's fuel efficiency changes as it speeds up or slows down (Yes, cars get more efficient at around 50-60 mph, then start to lose efficiency if it goes lower or higher to air resistance). Human beings also have to account for different factors, we don't work in a vacuum, nor are we as efficient at producing work with energy as cars or rigid bodies.Anonymoushttps://www.blogger.com/profile/06550842355330849595noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-59573275708975358692015-10-01T20:37:45.580-07:002015-10-01T20:37:45.580-07:00Without getting too nerdy, my general experience b...Without getting too nerdy, my general experience based on many calculators and personal weight loss over 5 years is that climbing steep grades (700-800 ft/mi) at a brisk pace (3-4mph, 15-17min/mi) and running back down them at a moderate pace (8min/mile) burns about 30-35% more calories than running on flat terrain at 7-8mph. I would definitely add 10-20% to the counter here for a moderate downhill run. Hope this helps!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-60498160889301488082015-08-27T19:14:08.177-07:002015-08-27T19:14:08.177-07:00Thanks for the info. Just returned from the mount...Thanks for the info. Just returned from the mountains of southern Montana where we hiked long and hard, a bit over four hours and up a bit over two-thousand feet. Upon returning lay down to take a nap and suddenly both hamstrings were in spasm and very, very tight and painful. It was quite difficult to regain balance and control and the pain level was quite high. Will now keep plenty of salt in me! Thanks again.Anonymoushttps://www.blogger.com/profile/08460851197836591737noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-1296001523453166332015-08-10T15:28:03.243-07:002015-08-10T15:28:03.243-07:00I agree with Anonymous there: W = F.D is not adequ...I agree with Anonymous there: W = F.D is not adequate. It completely ignores the work done by muscle fibers, which occurs everywhere in your body, at different rates and stresses. You can't use F = ma for chemical transport or work inside the body.Anonymoushttps://www.blogger.com/profile/11251884642836458044noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-62276905981728496362015-08-10T13:18:14.337-07:002015-08-10T13:18:14.337-07:00I have been looking for a method to obtain data fr...I have been looking for a method to obtain data from a gpx track that you must have used in the plots you have in this post. Did you do all the leg work yourself or did you use a software application/library?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-19603253103864219362015-07-07T05:00:50.291-07:002015-07-07T05:00:50.291-07:00Thanks a bunch for making this and putting it up. ...Thanks a bunch for making this and putting it up. It helps supplement my approximations of food I will need on my really long treks!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-61880954170416103272015-06-21T14:10:53.142-07:002015-06-21T14:10:53.142-07:00Condescending engineer is condescending. And wron...Condescending engineer is condescending. And wrong. Nutrition and calorie expenditure is way more complicated than a few basic physics formulas. Speed as a factor has much more to do with individual capacity for aerobic workload. The body is very efficient at shunting oxygen where it needs to go, but there's really only so much it can handle. When it fails at getting oxygen to muscles, you build up lactic acid and other metabolites from anaerobic metabolism.<br /><br />Sorry, you sound like an asshole when you point at F = M*A (a formula learned by most high schoolers) and then proceed to overexplain a point and miss the most salient features.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-89096216487433320362015-05-26T06:29:20.631-07:002015-05-26T06:29:20.631-07:00Hey, Thanks for the calculator. It's so much ...Hey, Thanks for the calculator. It's so much better than the one that comes with my fitness program Cheers! Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-12279427475920662532015-04-18T07:12:15.104-07:002015-04-18T07:12:15.104-07:00I am an engineer, so I'll clear this up for yo...I am an engineer, so I'll clear this up for you guys...<br /><br />The equation, W = F * D, is dependent on your velocity and the angle of your climb, and here is why..<br /><br />F = m * a, m = mass, a=acceleration. If you do a force balance and determine the net force working on you as you climb, you have to consider a few forces...<br /><br />Force of gravity, force of friction, and the force you apply as you climb. At constant velocity, your forces balance out to zero. The energy used, on the other hand, increases as you apply this force for a distance (hence force x distance). <br /><br />Gravitational acceleration is constant, BUT the angle you are climbing changes how you fight this force. The force of gravity needs to be "fought" more as your angle of climb changes, because you have less ground to rebound your acceleration (for every action, there is an equal but opposite reaction). Since the angle decreases how much the ground absorbs your acceleration, you have to balance that out with other forces, such as more work done by your hike. In addition, your fighting gravity more directly as you climb in elevation. So, the force of gravity plays a massive factor.<br /><br />Also, your frictional loss and other resistances tend to be functions of your velocity, so the faster you walk, the more you have to overcome to stay at a constant velocity.<br /><br />So, to wrap things up, we can go through the math.<br /><br />At constant velocity, your forces balance out (Newton's law... an object in motion tends to stay in motion...)<br /><br />SO:<br /><br />Fnet = F gravity + F walking + F other resistances such as friction and wind resistance<br /><br />Force = m * a <br /><br />acceleration due to gravity is g (9.81 m/s^2). It works in the opposite direction of your movement, so we will denote this as g. Gravity is where your incline comes into play. As your angle increases, the force of gravity increases. Inversely, gravity helps you out as you're going downhill, so the g becomes positive, thus less work required. <br />SO:<br /><br />F= m * g * sin (angle of climb)<br />The sin function is in there due to trigonometry, which is difficult to explain if you have never learned it, but it has to do with angles and triangles. <br /><br />If we assume constant velocity, your body is actually not accelerating, so F walking drops out. If you're actually physically putting work in to accelerate or decelerate, then that will increase or decrease. In addition, your frictional losses and resistances are dependent on your velocity, so that will increase as well.<br /><br />SO<br /><br />W = Fnet * D. As you increase in slope, your Fnet increases due to the gravity equation, as you accelerate for reasons other than gravity, your Fnet will increase, and if your velocity increases, your Fnet will slightly increase due to friction. If you are going downhill, you will have less of an Fnet due to the direction of gravity (switching from positive to negative).Anonymoushttps://www.blogger.com/profile/05398526574336354565noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-25948617065046635282015-04-04T08:26:59.051-07:002015-04-04T08:26:59.051-07:002 of 2: (...continued from previous post...)
--I...2 of 2: (...continued from previous post...)<br /><br />--It is also possible to have non-steep slopes that fall right into the ideal range when going downhill as to minimize energy used for increased pace/distance values (we move faster and use much less energy going downhill up to a point). A trail that has an average slope of around 2-8% for the downhill parts (whether a loop or out-and back trail) will actually decrease lower overall calorie-burn of around 25-100%.<br /><br />--Also it should be noted by anyone who uses such a calculator that total accent is always more than lowest-point to highest-point elevation change. For example, a trailhead starting at 5000 ft that summits a 7000 ft mountain might be an overall gain of 2000 ft, but should also include every bit of accent in between that may follow a temporary descent on the way to the high point. This 2000ft average gain could (and often does) increase up to (and possibly even more than) 100%. Using the above example, it could very well occur that the trail starting at 5000 ft could go up to 5500, down to 4500 (the trail-head is not always the low-point), and then could continue like this all the way to the summit. This adds lots of uphill hiking both on the way to the summit and on the way back to the trail head.<br /><br />--It is already known that your website's calculator averages out the entire trip, and of course assumes an out-and-back type trail. It must be noted, however, that for the case of loops, especially those that differ quite a bit for each half of those loops, these values can push or pull these extremes beyond the average even more. For example, a loop trail that goes uphill ever so gently (averaging about 2-4%, say) but returns back downhill slightly more steeply (4-8%) will burn MUCH less calories compared to a loop that involves a steeper (and therefore shorter) uphill and very gradual (longer) downhill can differ as much as (or possibly even more than) 400%. That's quite a variance.<br /><br />In conclusion, while your website's calculator has indeed been very helpful for myself as well as hundreds if not thousands of others, variance can (and often will) exist to the point that a calculated calorie-burn on this website showing 1000 calories burned could in reality burn as little as around 500 (100% decrease) calories and as much as 2000+ (100% increase) calories... with a total potential variance of 400% from low to high.<br /><br />A way to quick fix this calculation could very well be by adding a terrain steepness difficulty (in terms of sectional steepness as opposed to overall steepness) coefficient; also another coefficient could be used based on whether the trail is a loop or a one way out-and-back.. the one-way would require no coefficient, whereas the larger the difference/variance in loop sections (i.e., first half versus second half of loop) would play a role in either increasing or decreasing overall calorie burn.<br /><br />Nonetheless, thanks again for creating a very useful tool that is otherwise very difficult to find anything else like it! :)<br />Anonymoushttps://www.blogger.com/profile/06034707450825118165noreply@blogger.comtag:blogger.com,1999:blog-8190463771981947702.post-73071013858466673192015-04-04T08:25:34.444-07:002015-04-04T08:25:34.444-07:001 of 2:
Thanks for much for researching and desig...1 of 2:<br /><br />Thanks for much for researching and designing this very useful information! I've been interested in these calculations for a while now, and recently designed a spreadsheet based on exported data of a given hike route using only distance and elevation input variables. I have used your calculator as a base to judge whether or not my calculated values seem to carry any merit. After many hours and tweaks, I think I have assembled a very accurate spreadsheet. A few things to note:<br /><br />Using exported data, this gives me detailed information at small increments of change in rise (height) and run (distance). Think about a 1000 data points for a 4-6 mile hike. This has allowed me to calculate slope based on each increment, which basically breaks down into about 10-100 ft distance segments. I calculated a theoretical hiking pace based on the slope, as well as METs based on these pace increments. As a result, my values have averaged around your website's calculated values, although they do vary quite a bit a times based on the hike data. This is due to a number of factors:<br /><br />--You are calculating an average slope (and thereby unchanging slope value) from trail start to trail finish. This results in the same amount of calories being burned for any given distance increment from start to halfway. Same thing (although a lesser amount for assuming downhill) from half-way to finish.<br /><br />--Using lots of data this doesn't always average out in terms of calories burned given that some slopes require MUCH more energy to traverse, (moreso, of course, uphill, but also downhill). If the trail involves lots of steep sections this can increase the final calorie-burned value by as much as 50-100%. <br /><br />(...continued in next post...)Anonymoushttps://www.blogger.com/profile/06034707450825118165noreply@blogger.com