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Comment by kotyk | Hacker News Reader

I once tried to burn 3,000+ calories per day using just walking. I had heart issues and couldn't do intense workouts, so I set a goal of 20,000 steps a day.

To hit that consistently, I ended up walking 4–5 hours daily. It worked — I was burning massive energy — but it was hugely time-consuming. When I later recovered, I realized the same burn could be done in 40 minutes of gym effort.

Walking is absolutely underrated, especially for recovery and mental clarity. But in raw efficiency... it’s humbling how long it takes to match even moderate training.

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> I once tried to burn 3,000+ calories per day using just walking.

You'll generally burn about ~2k cals per day just being alive. An intense workout for an hour can burn maybe 500 on top of this. I think your math might be off somewhere if you walked a lot and figured that you spent a whole 1k.

Yeah, I too thought this number was unrealistic. I run, and I know that it takes about 60 calories per km (I run 10 km usually). To burn 3000 I'd have to... run more than a marathon (50 km, marathon is 42 km). Running marathon every day is... I won't say impossible, but is highly impractical (and actually impossible for most people who can run marathon). For an average runner, it takes 4-5 hours. So, I think that to burn 3k calories by walking one would need to walk way, way longer than 5 hours a day. Not sure even if it's possible to squeeze that much walking in a day.

The best way to hit 3000 is cycling. A reasonably fit (70kg-100kg) cyclist should burn 600-800 cal/hr riding at a moderate pace, so 3000 is a 4-5hr ride. It wouldn't be unusual for an enthusiastic amateur cyclist to hit that 1-2x/week.

However, if you assume that 2000 calories is pretty much maintenance and you'll burn that anyway, then you only need somewhere around an hour and a half or two hours cycling. Also if you can replace a medium commute with cycling, then it's not that difficult to hit that target just through active travel. (I used to regularly cycle commute approx 37kms each way and I could easily hit 1000 calories on just one of the journeys).

Yeah. It's easy to get over 3000 total daily calories if you have, eg, an hour of cycle commute per day and then add some purposeful gym or running on top.

Could do it far more biomechanically efficient on an elliptical, but overdoing cardio risks less type IIb (wiry appearance) and hypertrophic cardiomyopathy.

Or incorporate more strength training that increases type IIb adaptations and greater BMR.

For interest:

William Goodge smashes record after running across Australia in 35 days

  British athlete four days quicker than previous record holder who completed 3,800km feat in 39 days

  Spurred on by his mother’s battle with cancer, and with his father by his side, William Goodge crossed the finish line in Sydney just after 4pm on Monday.

  It brought an end to 35 days of pounding the pavement, striding the equivalent of two-and-a-half marathons a day.

May 19th, 2025: https://www.theguardian.com/sport/2025/may/19/william-goodge...

> Shannon-Leigh Litt has run 500 ultra marathons in 500 Days

https://www.stuff.co.nz/sport/360690060/northlander-runs-her...

Out of reach for most of us though.

Fat dudes burn significantly more than ~2k per day just being alive, or at least I did when I was younger. I lost significant weight on a 2300 calorie/day diet. So maybe the OP was 2500 for "being alive" and 500 for the workout?

Possible, and I considered that, which is why I put 500 cals for an intense hour-long workout, to imply that walking for a few hours will not even come close to 500 cals.

> walking for a few hours will not even come close to 500 cals.

No, not even close. I would expect 4-5 hours of walking to burn significantly more than that.

I could be wrong, but from my research and understanding, walking is one of the easiest things for us to do, only slightly more expensive than sitting up straight or standing.

On top of this, it doesn't "stack" well because of the low heart rate usage, meaning it logarithmically increases calorie costs (our bodies essentially amortize it), whereas lifting and carrying a heavy object for 20 seconds exponentially increases it.

For a normal person, it's about 100 calories / hr for sitting vs 200 for walking.

For a fat dude, it's about 150 calories / hr for sitting vs 350 for walking.

Source: google. Use appropriate doses of salt.

In general cardio will always use more energy than lifting because you can simply do much more of it.

Cardio is continuous work while lifting is work done a few seconds at a time.

Walking in particular is still moving your body horizontally through space. That horizontal displacement is the biggest determinant of energy cost for any given body, all things being equal.

Running only burns slightly more per unit distance because there's slightly more vertical displacement as you're literally leaving the ground between steps.

Fat dude doing 5 hours of walking a day would have no more knees within a month. It's good to aim to be less overweight, mostly because of the cancer and CHD risks, but also because it wears the body out faster mechanically and takes more relative effort to do everything.

BMR. Cut food by 1000 kcal, that's 1000 kcal that don't need to be metabolized.

This is what is kicking in when you do anaerobic exercises:

https://en.wikipedia.org/wiki/Excess_post-exercise_oxygen_co...

> Anaerobic exercise in the form of high-intensity interval training was also found in one study to result in greater loss of subcutaneous fat, even though the subjects expended fewer than half as many calories during exercise.

Walking essentially does nothing to your EPOC levels. A one rep maximum deadlift can elevate it substantially for hours. 10 seconds of suffering can trigger responses that hours of walking cannot.

My weight loss shows a huge difference in cycling vs. burning the same number of calories walking

> the same number of calories

How do you measure the calories burned ? Get 10 different devices you'll get 10 different measures.

Maybe they put their daily food intake and feces both into a bomb calorimeter https://en.wikipedia.org/wiki/Calorimeter and measure the difference?

> Maybe they put their daily food intake and feces both into a bomb calorimeter

Not at the same time, I would hope

EPOC only accounts for something like 60 additional calories burned in the next 24 hours...unless there is something unexplained going on, it's _greatly_ overblown how significant this actually is

...but it sounds sciencey and sexy so it's often repeated.

60 calories is what you burn when running 1 km. It's not insignificant :)

You will not burn 3000 kcal in 40 minutes of gym effort. Even burning 1000kcal in an hour requires serious fitness and burning 1200 is elite athlete level max effort for a full hour.

Calories burnt by walking, assuming flat surface are decently approximated by (distance_in_km x weight) formula so it is possible to burn a lot in 4-5 hours of walking but quite unlikely to hit 3000 unless you're very fit.

Going by my fitness tracker, a 1-hour 900kcal gym session is absolutely intense. On the few times I've hit that mark, I'm laid out on the ground and probably need to take it easy the next day.

More realistically, I hit 600-700kcal per session.

I think they mean all day calorie burn, not active burn.

Yeah but then they will not get close to what they can burn with 4 hours of walking by doing a 40 minutes gym session.

The delta is pretty close. Walking is ~200 calories / hour, but sitting is ~100/hr, so the delta is 100/hr. So 4 hours of walking might be as little as an excess of 400. cf a gym workout of 500/hr is also an excess of 400.

IOW, the total calorie burn in a day that includes 4 hours of walking is likely relatively comparable to the total calorie burn in a day that includes an hour of gym time.

Walking 5km/h at 70kg is 350kcal/hour. If you are heavy and unfit then it will maybe be 3km/h at 90kg 270kcal/hour but then someone that unfit is not going to be able to burn 500kcal in an hour in a gym anyway.

>>IOW, the total calorie burn in a day that includes 4 hours of walking is likely relatively comparable to the total calorie burn in a day that includes an hour of gym time.

It's a good point about the delta (the estimations are for a total burnt during activity not extra) but I don't think you can get the numbers close. People greatly overestimate how much you burn during gym session as well unless they are already very fit and move constantly during that session.

I've burnt over 1000kcal in an hour cycling and I'm over 50 and not super-fit. A few hills can make all the difference as it's difficult to be lazy whilst grinding your way up-hill.

Be aware the caloric estimates on gym equipment are like 20% over estimated.

1000 kcal per hour is 278w FTP if using common convention of 1 cal = 1 j of work (assuming ~20% COP). A lot of people who are very fit dream of such an FTP.

Well, looking at average ranges, 278w FTP would put me in the top 40% or so, which I would consider is reasonably average. Also, I'm reasonably heavy (around 100kg), so that probably makes it easier to put out some power whilst also meaning that I'm slow up the hills.

https://www.cyclinganalytics.com/blog/2018/06/how-does-your-...

That's a) self-reported and b) among cyclists who track their power i.e. have power-meter equipped bicycle and a head unit to record stats. Self-reporting inflate the numbers by itself but, since most people don't actually have a power meter or/and don't bike, that group is made from quite fit people by selection.

1000kcal in an hour is around 277 Watts for an hour. There are very few people who can sustain that without serious dedication and long hours for months/years.

I would think the more fit you are, the less calories you’re going to burn per unit of work. Because your body is more efficient.

As endurance hunters our bodies are tuned for efficient use of energy during low/medium paced exercise. Walking is awesome, and I try to get out there and do an hour a day, but I agree - you get much better results from the gym because our bodies aren’t specifically tuned for those types of workouts. Lifting weights also has a lot of tangible benefits for both men and women in the short and long term.

> As endurance hunters

There's no evidence for this.

But everyone should walk a little bit if only for the mental health benefits.

There’s actually a good amount of evidence for this. Here’s a basic look but you can dig in to other sources that will expand on how we know this.

https://en.m.wikipedia.org/wiki/Persistence_hunting

Lol yes there is. You can find people alive today who still do it.

We used to do it as children on the ranch. Running down sheep and cows is easy. Deer just take more time.

One of those being not being an otherwise healthy middle aged person constantly complaining about their back, general body pain, etc. I see people in their 70s even at the gym who look and seemingly feel great because they’ve been doing some resistance training their whole adult lives. Better than some software devs I know who never move and are in their 30s.

To get some idea of how efficient we can be look at studies of the Hadza, a tribe of hunter-gatherers in Tanzania, described here [1]. The men spend the day walking around hunting, or if they can't find game climbing trees to get honey, yet burn about the same amount of calories as sedentary men in western industrialized societies. The women spend all day moving around foraging and the results are similar.

[1] https://en.wikipedia.org/wiki/Exercise_paradox

>But in raw efficiency... it’s humbling how long it takes to match even moderate training.

Bipedal walking on mostly flat ground can only be matched by kangaroos' hopping in terms of energy efficiency.

laughs in cycling

Presumably by 3000 you mean 1000 over the ~2000 from your basal rate? 1000kcal per day from walking alone is about 3-4 hours of walking per day depending on weight.

Dangerous, inefficient, and time-consuming compared to moderate exercise and eating less. Caloric restriction is, by far, more effective than exercise for net deficit. Thunderf00t did a video on this. https://youtube.com/watch?v=mTABw0EyIWY

Another thing about walking is - while everyone's different, long walks really increased my appetite. While walking 4 miles daily (with some hills) was great in many ways, I slowly gained 20+ pounds over 2 years. Running didn't have same effect on me.

4-5 hours for 20k steps? Because of your heart issues?

I just checked my current stats. I have 15k steps recently from walking to and from my job. And that’s not counting the steps at the gym. I take off my watch since it’s often a hindrance during work outs.

I have a recorded 'hike' (on very steep logging roads) of 7 hours with a total expenditure of 1800 cal active/2500 cal total with an elevation gain of 3000' (the decent was way harder).

Are you walking for work?

Tell me how to burn 3000 calories in 40 minutes and I will be in perfect shape. It's a struggle to burn 400 in 30 minutes (hiit training, very challenging)

Depends on incline.

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