1300 Cals a Day

"Tom, sorry If I came off the wrong way."

No offense taken, Kevin. All part of the give and take in the forums.

I think there may be an element of truth about the body's unpredictability in any given short period of time. That's why I mentioned refining the process over multiple trips and developing a menu based on what worked most of the time, adding a bit extra if a trip will be more demanding; perhaps less for shorter, or less strenuous, trips. It's not engineering precise, that's for sure, but over the longer term, I have gotten it down pretty well for myself by processing the feedback I got from each trip and doing some more reading where indicated. I think each person has to go through the process and find out what their body requires. There are certain basic principles of physiology that apply to everyone, however, and that is where I started with my reading. And came back to read more as the experiment progressed. What I was trying to do in my original post was explain my understanding of the physiology involved and how it could be applied to the OP's question. And maybe get others involved in the discussion and thinking about their own situations. This is an interesting subject and I look forward to hearing from others.

" but they rely on knowing how much healthy burnable fat one has. I'm interested in learning more about this so I have a few questions.

1. I am wondering if you could explain a bit about how one knows how much "healthy burnable" fat they have.

2. From where did you get the percentages for how many carbs, proteins, and fat are burnt while hiking? Are those numbers standard?

3.Can you explain the process for finding out that you burned ~65% fat from your total calorie loss each day?

Geez, I'm sorry I have a lot of questions, but I just find this very interesting. You can certainly recommend a source (Is it the Exercise Phys book?) and I can try to learn more myself. Your explanation just really helped to make sense of what is probably somewhat complicated when read from a book and applied to backpacking!

Thanks!"

Hi Andrew,

OK, I'll take a stab at it.

"1. I am wondering if you could explain a bit about how one knows how much "healthy burnable" fat they have."

I am 5'8" and my weight is pretty stable at 137#. This is on the lean side and my assumption is that I do not have much fat that I can afford to burn healthily. Maybe a pound or two, but I prefer to hold that in reserve and not press my luck. So, in the month or so before, say, a 10 day trip I start eating more than I normally do. It works out to about 400 extra calories/day and results in ~4# of extra body fat, 12,000-13,000 calories. My assumption is that this excess fat is "healthily burnable" fat.

"2. From where did you get the percentages for how many carbs, proteins, and fat are burnt while hiking? Are those numbers standard?"

The numbers are provided as ranges, never a precise number, in most exercise physiology texts. Most of them deal with competitive athletes who are exercising at a much higher intensity than we lowly backpackers and, therefore, deriving a much higher percentage of their energy from glycogen. The range I started with, from "Exercise Physiology" 6th Edition, by McArdle, Katch, and Katch, gives a range of energy provided from fat as 20-80%, depending on the intensity of the activity. I chose 65% as a starting point, based on a guess that more energy would be provided by fat due to the lower intensity of backpacking. By luck, based on my experience so far, it was a fair guess. Richard Nisely also provided information that tracked with this number for my pace, which is around 2.5 mph. Protein as a substrate for energy in endurance is generally held fairly constant in a range of 5-10% until glycogen stores are exhausted, at which point it can provide up to 15% of total energy, according to McArdle, et. al(see page 41). The remainder must be carbs. The additional piece of info was total calories used for an activity-there are a number of algorithms out on the web that will give you this info. For me ~4000 calories/day was indicated. I used that as a starting point and over time ended up at 4400 calories/day. I guess that rolled question 2-3 into one long winded answer. Hope it makes sense. If not, post again and we can continue the dialogue. Also, if you Google "protein as energy substrate for endurance athletes", you will find some interesting reading. A very interesting field where each backpacker is an experiment of one, IMO. Have fun! I sure have.

For years I have correlated my weight with a given thickness of abdominal skin via the "pinch test". Not overly precise, but close enough. For me the fold of skin is ~3/8" when I weigh 137#. After gaining ~4# it will be ~3/4". When I return from a trip, if I have calculated the amount to be gained correctly, my skin fold has returned to its usual ~3/8". Mostly it is around that, sometimes a bit less. It is a means of calibrating the amount of fat I need to put on, and because of that I track it closely.

Tom, thank you for such a nice response. I have a much better idea of where to start with this now and I appreciate you taking the time to give me a boost.

Awesome posts man! They are really helpful to me.

I have to throw some additions in here.

You need an excess of 500 cals a day to gain 1 pound a week so 400 cals a day at 4 weeks (or roughly 1 month) won't net you 4 lbs of mass. Closer to 3 pounds is more likely. Second on that, if you're getting regular exercise that won't all go to fat. With my daily regiment it would mostly turn to muscle assuming it's not excess calories from junk.

On how much fat you have, you can't assume fat based on weight. At 5'8 and 137 you could still be 20%+ fat. The caliper gives you a better idea of whether that's true but we don't need people reading this to just assume fat percentages based on weight.

Disclaimer: I'm not a dietitian but I have gone from 210 lbs and probably 30% fat to 145 lbs and around 6% fat so I'm fairly competent when it comes to food and exercise.

"I have to throw some additions in here."

Hi Chris,

First off, congratulations on going from a 210# blob to a lean, mean hiking machine. Awesome!

"You need an excess of 500 cals a day to gain 1 pound a week so 400 cals a day at 4 weeks (or roughly 1 month) won't net you 4 lbs of mass. Closer to 3 pounds is more likely. Second on that, if you're getting regular exercise that won't all go to fat. With my daily regiment it would mostly turn to muscle assuming it's not excess calories from junk."

Last time I looked, a month was either 30 or 31 days, and 31 x ~400 calories/day gives 12,400 calories, or a little over 3.5#. An approximation, to be sure, but closer to 4 than 3 if you want to quibble. This is because I am not talking about a lab experiment but, rather, a real world exercise involving one person without access to precision measuring instruments. That is also why I had to refine it over multiple trips until I got a result that was more or less repeatable and within an acceptable range based on how I felt during and after my trips, and how much I weighed going in and coming out. In any case, I was less interested in the numbers per se than the methodology.

Trust me when I say that I get plenty of exercise, Chris, and that I am not anywhere near 20% body fat, even after gaining ~4#. When I said ~400 extra calories/day, I meant calories above and beyond what it takes to maintain my weight and strength with a fairly rigorous training schedule. I probably should have added that they are heavily oriented toward carbs and fat, so if I gain weight I have a pretty good idea what form it is going to take, and correlate it with a crude digital caliper test. As for where your extra calories might go, that would depend on whether they were balanced protein to support muscle gain, or whether they were fat and carbs, in which case they would go to fat, just like anybody else.

"On how much fat you have, you can't assume fat based on weight. At 5'8 and 137 you could still be 20%+ fat. The caliper gives you a better idea of whether that's true but we don't need people reading this to just assume fat percentages based on weight."

I don't assume fat based solely on weight. That's why I mentioned the digital caliper test to correlate it. I think anybody who reads that post would be able to figure that out. If not I apologize for my lack of clarity.

Hi Andrew,

If they turn out to be helpful, it will have been worth it to me. I hope they help you find a method that works for you. If so, it should help lighten your pack and increase your enjoyment. I know it did for me. Best of luck.

Tom-

I wasn't trying to imply that you personally were high fat, just that a height and weight mean nothing as far as body fat is concerned. Calipers help give you a general idea but aren't that exact either especially without proper training on their usage.

Since you got technical with the days, a month can range from 28 to 31. :-P

Diet is so personal I'm not even sure it's worth giving someone else advice over the internet. There are so many variables you can't account for that anything you tell someone is generic at best.

Whether you carry 4 pounds of fat in your body or on your back it's still 4 pounds. Your muscles, bones, heart, lungs, etc. don't care. I don't see the point of trying to fatten up before a trip.

"Diet is so personal I'm not even sure it's worth giving someone else advice over the internet. There are so many variables you can't account for that anything you tell someone is generic at best."

Chris,

People give advice in the forums all the time. Everybody gets to put their 2 cents worth in and people can use it or not. Advice was sought, and I tossed my 2 cents worth in. I've found it personally useful to me on many occasions and Andrew, at least, apparently thought there were some things in my post worth following up on. He's a big boy, he'll figure out what, if anything, makes sense, and what does not. Yeah, diet is personal, but basic physiology applies to everyone; well, almost everyone. ;}

"just that a height and weight mean nothing as far as body fat is concerned. Calipers help give you a general idea but aren't that exact either especially without proper training on their usage."

Height, I agree, but weight correlated with body fold thickness, over multiple iterations do, IMO, in the context I use them. The measurement doesn't have to be exact, as I have mentioned time and again. It has worked well for me in practice, so I am comfortable enough with the methodology to present it to others to take or leave. If it works for someone else, too, so much the better. If they try it and it doesn't, they've eliminated one dead end and probably learned something in the process. Call it a layman's version of peer review, if you will. Scientists do it all the time in the adult world.

"Whether you carry 4 pounds of fat in your body or on your back it's still 4 pounds. Your muscles, bones, heart, lungs, etc. don't care. I don't see the point of trying to fatten up before a trip."

There are at least 2 points(and probably others that I don't have at my fingertips): 1) To gain the calorie equivalent of 4# of body fat requires more than 4# of food, which you will have to carry; 2) Carrying 4# (or more) of food takes up space up in your pack, potentially requiring a larger, heavier pack, especially as your trip length increases. You might find the Arctic1000 website discussion on this useful. Dr. J, Roman, and Jason all put on considerably more than the measly 4# I am talking about for these reasons. "Since you got technical with the days, a month can range from 28 to 31. :-P"

I think for purposes of general discussion, most folks would go with something that occurs 11 times a year rather than something that occurs once every 4 years, wouldn't you agree?

4 pounds of fat is 4 pounds of fat, I don't care how you carry it. I never mentioned 4 pounds of food. As a general rule it will take less energy to burn 4 pounds of ingested fat (assuming it's done properly and never stored) than it will to convert and burn 4 pounds of stored body fat. In essence that means 4 lbs of fatty food yields more energy than 4 lbs of stored fat. Likely a minor difference but a difference none the less.

I do agree carrying 4 lbs of fat takes up pack space but the Artic 1000 is by far an exception to almost all treks. If everyone followed that example the number of people who successfully thru the AT or the like every year would dwindle to low double digits at best. We have resupply so we don't have to carry 56 pounds of food on our backs.

No healthcare professional will ever advocate putting on excess fat in all but the most extreme circumstances.

Anyway, I'll leave the rest to the registered dietitians.

"4 pounds of fat is 4 pounds of fat, I don't care how you carry it. I never mentioned 4 pounds of food. As a general rule it will take less energy to burn 4 pounds of ingested fat (assuming it's done properly and never stored) than it will to convert and burn 4 pounds of stored body fat. In essence that means 4 lbs of fatty food yields more energy than 4 lbs of stored fat. Likely a minor difference but a difference none the less."

I'd be very interested in any credible references you could supply to back this up. I won't hold my breath.

Good conversations you got going guys. You both make good points I think.

As to the health of this method, I don't know. Is it healthy to gain weight to prepare for a time of relative famine? Well, it's prevalent in nature for animals that rely on seasonally driven abundance of food, but this is a case of necessity, which Chris stated is the only reason for really attempting this kind of thing. I would imagine that if given a choice no creature would choose hunger. So while it may not be healthy, it may not be too harmful to use on certain hikes that would allow it. I treat technique like this the same as I would treat sleeping bag, shelter, or pack choice. No two hikes are the same and it's best to have the most knowledgeable from which to form decisions on. That is why I asked for further information from Tom.

I think it is important that I asked Tom for this advice as opposed to him promoting it. I don't think it is right to act as if he is passing off some crazy advice unprompted. He was kind enough to answer my questions and give me an idea of how I should go about researching this further. By knowing his thoughts on the matter I have a better idea of what I should look at and what questions I should try to answer for myself. I know that I am not the same as Tom, but his experience can be used to guide my own.

Chris, I should point out that your comments have also been incredibly helpful in guiding me on this new interest which may or may not become something I really learn about.

Thanks to you both for having a productive conversation with each other. I hope that the discussion can go on.

Storage in the adipose tissue is catalysed by lipoprotein lipase, the activity of which is stimulated by insulin. When sugar/insulin level is low, body doesnt store fats. It uses fats directly from diet. If you want to maximize fat metabolism then avoid energy bars that are filled with sugar. Storage and mobilisation of fatty acids require extra work.

I've never researched actual numbers till now but since you asked and assuming I'm reading it right (I could be off by 3 kcal/g if it cost the same to retrieve as it does to deposit):

Gross cost of depositing 1 g fat = ~12.0 kcal/g

Since fat gross yields ~9 kcal/g that's a net cost of ~3 kcal/g to store it.

So in essence, stored fat has a net yield of ~6 kcal/g versus the ~9 kcal/g of readily digestable fat.

Net yield = gross yield – net cost

Comes from:

Spady D W, Payne P R, Picou D & Waterlow J C – Am J Clin Nut
Millward D J, Garlick P J & Reeds P J – Proc Nutr Soc

Cost body fat reserves ie. those fats have been stored before the trip is not really relevant because you have already paid it off. It is basically free calories! Cost of mobilization is minuscule compared to carrying and digesting dietary fats. What is relevant here is metabolism of dietary fats. If you eat more fats then you burn then extra fats will be stored and you will get only 6kcal/g from those fats. (I havent checked the reference.)

To know exactly how much fats you are burning at given MET is bit complicated and I dont have any reference with me right now. May be Tom can post some of Richard's original posts if he has bookmarked them.

okay – stepping out on a limb here and totally ready for the debate that may ensue… but is risking your health, screwing with your metabolism and heart health, really worth saving a few pounds in food weight?

Lots of things are a risk to someone's health. Fast food, too much red meat, alcohol, tylenol, lipitor, etc… I have yet to see a drug ad on tv that does not list side effects. It does not mean those drugs are bad, just means that's the nature of the beast. I would take what, in my opinion, is at most a minor risk once or twice a season…maybe.

I can't speak for others, but I'm not planning on starving myself or anything. Lots of times when I hike I find that I lose my appetite and end up with leftovers. I want to stop carrying extra food, but I wouldn't want to be unsafe about it. So, I think it would be cool to plan my menu based on the fact that if this occurs I would be giving my body what it needs to successfully metabolize my fat reserves. This will allow me to safely hone my food to the essentials. I consider all this learning to be safer than just taking less food and being hungry in such a way that my body is using muscle for energy.

As for screwing with metabolism, well, I think working out, dieting, stressing, etc.. do the same thing. Metabolisms are adaptive aren't they?

I would need to know more about how this could possibly be bad for your heart. I am obviously new to this idea, but I don't see the connection.

"Storage in the adipose tissue is catalysed by lipoprotein lipase, the activity of which is stimulated by insulin. When sugar/insulin level is low, body doesnt store fats. It uses fats directly from diet. If you want to maximize fat metabolism then avoid energy bars that are filled with sugar. Storage and mobilization of fatty acids require extra work."

right on.

gaining and loosing weight is not simply about numbers.
WHAT your body does with those calories is what counts.
When insulin is high your ability to utilize fat stores is diminished and carbs are stored as fat. Eat low glycemic foods and your body with utilize fat for energy.

"Cost body fat reserves ie. those fats have been stored before the trip is not really relevant because you have already paid it off. It is basically free calories! Cost of mobilization is minuscule compared to carrying and digesting dietary fats"

Thanks, Huzefa, for saving me the trouble.

Sorry, I didn't bookmark Richard's posts. I used them to corroborate my own results and moved on. Maybe if Richard is still monitoring the proceedings he'd oblige you and everybody else with his input. He knows quite a bit about this subject, and things are starting to get interesting, at least to me.

Keep up the good posts, Chris. Eventually all of us blind squirrels may get lucky and find a nut. :)

"but is risking your health, screwing with your metabolism and heart health, really worth saving a few pounds in food weight?"

Welcome aboard, Laurie,

Your question begets another question: If a person is healthy, active, and following a healthy diet on a regular basis, how does adding ~4# of body fat over a month, which is burned off by strenuous activity within 8-10 days, lead to the risks you pose?

"If everyone followed that example the number of people who successfully thru the AT or the like every year would dwindle to low double digits at best. We have resupply so we don't have to carry 56 pounds of food on our backs."

This brings up another consideration: Maybe the dietary approach should be adapted to the type of hiking being done.
If I am hiking a trail where resupply points are frequent and easily accessible, like the AT, it would make a lot of sense, at least to me, to stay lean and carry a balanced diet that met my total calorie needs on my back. The weight involved wouldn't be significant if I was resupplying every 3-4 days or so, and pre trip planning/execution would be a whole lot simpler. It's when the trip extends out beyond a week that the weight involved in carrying my total calorie needs on my back starts to become a burden, and a lot of my trips to date have been in the 9-10 day range, with a fair number out in the 13-15 day range and one at 17 days. Iteratively analyzing these trips has led me to develop the system I have posted here, basically a mini version of the Arctic1000 dietary system. It has been tested out to 10 days so far, with satisfactory results, but I have not gone on any longer trips recently. Beyond 10 days, I think I would have to put on more fat then I would personally be comfortable with, and would be faced with the same problem Dr J & Co faced; that is, having exhausted my body fat, I would be required to carry more food on my back for the duration of the trip to make up the deficit. That has been an effective deterrent so far. So maybe it makes sense to tailor dietary planning to the hike.?

Tom… I guess I just see that with a 1300 calorie a day diet this person runs a few risks… such as using muscle stores, lack of energy to the muscles, exhaustion, etc. I also see a metabolism that would start to go into starvation and then affect the body post-hike (caloric storing and possible weight gain). I also see a pre-hike issue with high lipids and sugars in order for an active adult to gain four pounds prior to hiking. That's where I meant bad for your heart… eating the amount of calories needed to gain weight prior to a trip isn't easily done in an active adult with a heart healthy diet.

Sorry I just don't understand the reasoning behind the weight gain from a health perspective and how you can be positive you are burning fat and not lean muscle tissue. Not to mention, even a small weight gain or loss can affect how the body engine runs.

My other concern is lack of protein in the diet. I see lots of dicussion about making this really high fat and understand that on the trail… but protein is essential to muscle repair. Does such a low protein diet seem wise on the trail given the extra work such an activity puts on our muscles?

I'm not trying to be argumentative… just looking at a different perspective.

"I've never researched actual numbers till now but since you asked and assuming I'm reading it right (I could be off by 3 kcal/g if it cost the same to retrieve as it does to deposit):

Gross cost of depositing 1 g fat = ~12.0 kcal/g

Since fat gross yields ~9 kcal/g that's a net cost of ~3 kcal/g to store it.

So in essence, stored fat has a net yield of ~6 kcal/g versus the ~9 kcal/g of readily digestable fat.

Net yield = gross yield – net cost

Interesting reading, Chris, but it intuitively didn't make a lot of biological sense to me, so I did some Googling.

According to Tom Brady in Nutritional Biochemistry, p. 306:

1) It costs ~3% of the total energy content of a dietary triglyceride to deposit it as body fat.

2) It costs ~23% to deposit carbs as body fat

3)I didn't check protein, but it's even higher.

According to Jie Kang in Bioenergetics Primer for Exercise Science(Forgot to get the pages but look for Thermogenic Effect of Food or TEF):

1) It costs 0-5% of the total energy of a dietary triglyceride to deposit it as body fat.

2) The figure is 5-10% for carbs.

3) 20-30% for protein.

The source you posted was for studies done with malnourished babies and animals, and there was apparently some controversy over the findings. The 2 studies I cite were done with human subjects and seem more intuitively more realistic to a lay person like myself. I guess I'm sitting here thinking that I would be be downright feverish if I was burning up 12 calories for every gram of fat I deposited. Not to mention that I could never have gained that ~4# of fat based on the extra food I ate. But I did, and do. I'm open to further input but, at this point I'm skeptical of the figures you have given. To be honest, though, this is an evolving field and there is a lot that is poorly understood. And the energy cost of depositing body fat does depend on what the substrate is, just not at the level you posted, IMO.

"Tom… I guess I just see that with a 1300 calorie a day diet this person runs a few risks… such as using muscle stores, lack of energy to the muscles, exhaustion, etc."

Hi Laurie,

I couldn't agree more. I think the discussion veered off in the bushes at some point from OP's original question. In my first response to Paul, if I recall correctly, I told him I thought he had adequate energy stored as body fat to do the trip IF he took in adequate carbs to support fat metabolism and adequate protein to provide the amino acids metabolized to produce energy plus rebuild tissue. From there it segued into how that same approach could be applied to backpacking in general in an effort to save weight. It assumes a healthy, fit individual who gets a lot of exercise. Dr J, Roman, and Jason used this strategy on the Arctic1000 with no apparent ill effects, and I have used it for the last 5 years on 9-10 day trips with no apparent ill effects. Muscle loss is the obvious concern, as you pointed out, and I am constantly evaluating as I go along. I'm sure I lose a little muscle mass, but it isn't discernable in my strength workoputs after a trip and, so far, I can recover and do it again in 3 weeks or less. And my doc tells me I'm in excellent health every year, so I guess there haven't been any side effects so far. Knock on wood but, then, nobody gets out of here alive anyway. :) I wouldn't recommend it for everyone, but when Andrew inquired, I thought I'd put it out there for him and anyone else who might find it worth a look. I think your concerns are well taken, and anybody with any health issues should not consider this. Maybe something will show up with me on down the line but, based on my experience so far, I'm optimistic. And if anyone comes up with hard evidence that I am on the wrong track, I hope they will post here or PM me, beecause I want to be the 2nd to know about it. Besides, I'm delighted that it's brought so many people into the discussion. That's what BPL is supposed to be about. I love it.

Ok, I've watched this thread for a while. I'll jump in now…

I'm 5'9-10", and 180-200 lbs.

I have crash dieted in the past, paying fastidious attention to my caloric intake and limiting myself to 1500 calories a day. I know that this isn't healthy but I figured, heck, I'm a doctor, so I can monitor myself. Hubris, I know… Anyway, I can lose 15 pounds in a month doing this.

My point is I WAS MISERABLE. I was starving all the time. I would gnaw every scrap of flesh off of apples out of desperation, leaving a ravished core upon which even a goat couldn't find any decent nutritional value, but by God I was going to get every one of those hundred calories that I had allotted myself!

I can't imagine doing this AND hiking 20 miles a day.

If you try to hike on 1300 calories a day, brother, I guarantee that you will not have any fun. That's not 'hiking'- that's 'death marching.' That is something that is endured rather than enjoyed.

Heck, cutting down to 2000 calories will still have you losing weight. I recall a calculation for a hiker making 18 miles a day with a 3000 foot elevation gain that resulted in an estimated >6000 calories of metabolic activity for the day.

"My point is I WAS MISERABLE. I was starving all the time. I would gnaw every scrap of flesh off of apples out of desperation, leaving a ravished core upon which even a goat couldn't find any decent nutritional value, but by God I was going to get every one of those hundred calories that I had allotted myself!

I can't imagine doing this AND hiking 20 miles a day.

If you try to hike on 1300 calories a day, brother, I guarantee that you will not have any fun. That's not 'hiking'- that's 'death marching.' That is something that is endured rather than enjoyed."

Dean what you've posted is something else I was thinking about. I've successfully lost 170+ pounds (that's not a typo) in the last 12 years… but I didn't do that by going below 3000 calories on the trail… I just don't see that as a safe or pleasant place to do that.

I just don't think I'll every get so much into lightweight backpacking that I will cut the food so much that I am trying to use my bodies fat stores as a planned part of the menu.