What will happen to me with the calorie deficiency? I've plenty of fat reserves...

Current plan is: 100g Oats in the morning, dry.

Lunch/All day: 100g Nuts

Dinner: Various dehydrated Meals.

Not a lot, will be doing this for 10 days. Am I mad? Should I at least add some dried fruits?

Yes, the fruits would be a good addition.

A multi-vitamin, too, is an almost necessity given that diet.

Survive, sure. But man are you gonna crave other stuff!!!!!

Yea that would be rough for 10 days. I might be kinda hypoglycemic but i find that when i dont get enough to eat on multi-day trips, i get a little sleepy while hiking and i have a really hard time getting out of bed in the morning. Maybe add some coffee :). Good Luck

Man I'd be so hungry but you'd certain survive if you drip calories so as not to bonk/lose mental energy and have an accident.

1300 calories per day is a pretty restricted calorie intake even for someone who is sedentary. For someone trying to cover distance, frankly, I think it is ill advised. I would guess that you are trying to loose weight, reduce your pack weight, or both. At 1300 cal/day, I suspect you would probably loose as much muscle weight as you would fat. Loss of muscle can really make you feel lousy; weak, head-achy and crampy. A lot of this comes from by products of protein breakdown; some, I suspect, from incipient malnutrition. You could probably do what you are planning but I don't think you would enjoy yourself.

I hiked the JMT last summer on 2700 cal/day. For the first few days there was no problem; the combination of fatigue, altitude and dehydration really reduces ones appetite. Beyond those first days, my appetite returned and I felt that I had almost enough food, mostly. But, I lost nearly ten pounds on the through-hike. I don't think I would have enjoyed having much less food along though.

I think you may want to re-think your food planning; especially if you want to enjoy the trip.

Edited by Rincon on 07/16/2009 13:58:56 MDT.

If I'm remembering correctly an adult male body will go in to starvation mode if you consume under 1500 a day. You're highly likely to go in to ketosis as well.

How tall are you? How much do you weigh? How old?

Edited by simplespirit on 07/16/2009 14:00:54 MDT.

I'm 25, am 5 foot 9 tall and weigh 177 pounds.

Loaded up for 10 days, my packweight is 9.6kg, inc food on this diet.

I'm thinking of adding some pumpernickle, dried fruit to the mix, possibly some salami too.

I calculate that you need 18-1900 as a base. That assumes zero activity so I'd carry at least that much.

Ray Jardine in Trail Life makes a big point about NOT skimping on food. He's thinking more about mega-hikes (AT, PCT, CDT) so maybe you'd be ok for 10 days.

But if lack of food clouds your judgment, or makes you light-headed and you trip and injure yourself, you might find yourself in a big heap of trouble, or worse.

It is not clear to me that relying on fat reserves will work, as others have pointed out. I personally wouldn't take such a chance.

not only do you screw with your metabolic rate - your body doesn't just live off the fat stores... it will use your muscles stores as well - not a good idea

Sounds like no fun. Is fun part of your goal? What usually happens when people bring too little food: 1) they quit 2) they mooch off others 3) they call in unjustified rescues.

A side note. A few years ago there was a somewhat off kilter guy doing a long hike on the pct. His diet: 2 poptarts and three cups of coffee a day. He claimed to have lost 80 pounds in just over two weeks. The "before" photo contrasted with him lifting up his shirt to everyone seemed to support it. I told him that he was risking a heart attack. Most other thruers said similar things and there was even talk of calling some sort of psycological services. His enthusiasm for the endeavor wasn't tarnished though.

Edited by peripatetic on 07/16/2009 16:10:01 MDT.

You're crazy. Carry more and better food or be miserable.

You would lose weight hiking.

Also, rapid weight loss can pull toxins and ickies out of your fat stores - and those are not good in large rushes to your liver!

So while one can in theory live on 1300 a day, I cannot imagine you'd find a Doctor that would say it is a great idea when you must rely on so little.

As well, beyond brain function food fuels your inner heat. Starving yourself you will be much colder - and again, more likely to make mistakes if your blood sugar gets too low.

As well, consider this: if you don't get enough food your body will consume your muscles also. And that is what you don't want to be doing!

Would not worry about toxins in your body being released. BUT- you need far more calories than you have allowed. At least add some probars or big sur bars to you menu. They taste good and have lots of calories. Endurance athletes consume vast amounts of calories- on the tour de france 10000 calories would not be excessive. You might not exert yourself like Lance, but you will need far more than usual. Even if you want to lose weight you should eat far more than 1300 calories.

someone correct me if my calculations are wrong---100gms oats=360 cals----100gms pine kernals= 700 cals---total 1060 cals---surely a dehydrated meal is more than the 240 cals so where is the total figure of 1300 cals coming from

Nuts are a bad idea for this type of diet. Your main source of calories should be complex carbs/protein. You need this to burn your fat reserves and to avoid metabolism of your muscles. Dont take dry fruit or any sugar. This affects fat metabolism.

How much fat reserves do you have? You will need a LOT for 10 days.

I am currently experimenting with sugar free crunchy muesli: rolled oats, wheat flakes, oat and wheat bran, apple juice concentrate. I enjoy it as a snack. 12%protein/75%carbs. On my hike next weekend I plan on taking whey protein concentrate or roasted soy and sugar free muesli. My hikes are short and I would like to convert as much body fat to lean mass as possible.

For hikes longer then a week, if you run out of fat reserves you will need to eat 3000-5000 cal/day depending on terrain/pace to avoid burning your muscles. Nuts, seeds, legumes, peanut butter and cheese are good high fats/high proteins food.

Keep in mind that the key to make such a diet work is to learn controlling your pace. Make sure you are NEVER out of breath specially on uphills. Whether 1300 cal will be enough will depend on many factor such as your food choices, terrain, pace, metabolism, fitness, walking technique etc.

But unless you want to dig nutritional science, I suggest you listen to others.

"I've plenty of fat reserves.."

Yes, you are mad.

You will feel miserable, lose muscle and fantasize like crazy about pizza. But worst of all is that your body will over-compensate after the event, and you will very likely end up putting on more weight than you lost (and more of that weight will be fat instead of muscle). It would be a very unhealthy type of weight loss.

"I'm 25, am 5 foot 9 tall and weigh 177 pounds."

How much of that 177# is spare body fat?

If you have, say, 15# of "healthily burnable" fat, that would provide you with ~52,500 potential calories of energy if you had adequate dietary carbs to support its metabolism plus enough protein to keep your body from cannibalizing itself. If you hiked at ~2.5 miles/hour you would probably be burning in the neighborhood of 30% carbs, 5% protein, and 65% fat. I have figured out by trial and error, some study, and post trip analysis of my body weight differentials that I burn around 4000-4200 calories/day of which ~65% come from fat. If you burn calories at even close to that rate, you would need maybe 45,000 calories for a 10 day trip, allowing some extra for your greater weight(I weigh 137#). 65% of that figure would be ~29,250 calories from fat; 30% of that figure works out to be 13,500 calories from carbs, and 2250 calories from protein. Based on this you would need to carry 13,500/4 calories per gram = 3375 grams of carbs/~28 grams per ounce = 120.5 oz/16 oz per pound = ~7.5# of carbs to burn 7.2# of excess body fat on your 10 day trip, based on parameters I have found work for me over the last several years. Even if my parameters are of by 20-25%, either for you specifically, or just for everybody but me, you have plenty of body fat to get the job done, provided you carry enough carbs to support its metabolism. I didn't do the math for 5% protein, but it's a trivial exercise. Bottom line, you should carry 7.5 to perhaps 11# of complex carbs and whatever the protein at 5% works out to be to have a chance of pulling this off without doing yourself some serious damage. Good luck if your heart is set on this.

The figure of 5% protein is meant to refer to protein for energy production. Total recommended daily intake of protein is considerabley higher. Estimates vary, but one recommendation specifically for endurance athletes in "Exercise Physiology" 6th Edition by McArdle, Katch, and Katch, p. 40, is 1.2-1.8 grams per kilogram of body mass. I carry 70-75 grams per day for a body mass of 65 kg and it seems to work fine, so far. NO detectable weakness, loss of lean muscle.

Edited by ouzel on 07/17/2009 21:19:19 MDT.

Impressive math Tom, however I don't think the human body can so effectively burn all your available fat like that in a span of 10 days. I don't think fat on your body is like gas in your car's tank.

Ok Guys, so what heathy carbs can I take with me as extra?

THanks

With that diet you will burn muscle and not fat. Protein is very important for muscle recovery, and even ultralight backpacking can be tough on the muscles. I would highly recommend you reconsider, but I am no doctor or nutritionist so this is strictly based on my knowledge of the subject.

"Impressive math Tom, however I don't think the human body can so effectively burn all your available fat like that in a span of 10 days. I don't think fat on your body is like gas in your car's tank."

Have you ever tried it, Kevin, or read up on exercise physiology? I tried it willy nilly, then read up on it and then went back and tried it again in a more disciplined manner. It works just like it's supposed to, at least for me. It's not as precise as a gas tank; after all the body is not a car, but you can sure get in the ball park fairly quickly and then refine your intake more precisely as you gather data, trip by trip. Maybe think about it some more?

Tom, sorry If I came off the wrong way. When I said impressive math, I meant that, because I'm the same way, I calculate everything.

I have done a lot of research on nutrition since I started weight training 2 years ago. I have gone on for months on carefully planned diets to bulk up or cut fat. I've planned and tracked daily calorie and carb/protein/fat intake as well as calories expensed. I'm not a pro though by any means.

What I learned is that in any given short period of time (a week, 10 days), my body can act in unpredictable ways. You can plan and think "well, if i have a calorie deficit of x calories per day, then in 1 week I should lose x pounds". But that's rarely the case.

Now, over a longer period of time, the weight change will approximate my original estimations.

Edited by kjyang on 07/18/2009 10:32:07 MDT.

Great post Tom. Those are some neat calculations, 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!

This site has a lot on nutrition info.

Nutrition

"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.

Edited by simplespirit on 07/20/2009 09:19:43 MDT.

"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.

Edited by simplespirit on 07/20/2009 19:33:12 MDT.

"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

Edited by simplespirit on 07/21/2009 05:21:21 MDT.

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.

Edited by Laurie_Ann on 07/21/2009 20:33:42 MDT.

"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.

Edited by acrosome on 07/22/2009 06:03:51 MDT.

"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.

Edited by Laurie_Ann on 07/22/2009 07:15:42 MDT.

The only few hikes I've heard of people using body fat stores is Arctic 1000 and Coups hikes that were hundreds of miles and no resupply.

Tom,

I'm glad you found updated information. Regardless of the numbers though, your info still agrees with me that you get less total energy from stored fat than from readily digestible fat. The only way it would disagree is if storing calories as fat didn't cost anything. Or did I miss a zero in there?

As to Hufeza's statement that that loss of energy doesn't count because you took that loss in the past. Well, that's an interesting way of looking at things but sounds like Enron accounting to me. If I paid $10 for a $5 item a month ago, that fact won't be any different today. I still paid more than it was worth. Calories don't appreciate in value unless you guys know something I don't.

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

Hi Dean and John,

I've been hoping you two would join this discussion at some point. I've got a request to make. Would you both go back to page one of this thread and read my original post to Paul's OP, with the idea of critiqueing it? You both know far more than about human physiology than I and I'm genuinely interested in getting to the truth of the matter, whether it's my position or something entirely different. Suffice it to say I didn't recommend that he hike on 1300 calories/day. Indeed, it would be impossible. It's just a matter of where the calories come from and the impact on his body.

To John,

I've been using almost exactly the same approach as the Arctic1000 group for the last 5 years now, two strenuous 7-10 day trips/year with excellent results. I figure the same principles apply, regardless of trip length.

Hopefully, we will hear soon from Richard N. as well.

""Regardless of the numbers though, your info still agrees with me that you get less total energy from stored fat than from readily digestible fat. The only way it would disagree is if storing calories as fat didn't cost anything. Or did I miss a zero in there?"

Chris,

Yup, you missed the zero, at least partially. Your own source mentions that it costs zero energy to break down and deposit dietary triglycerides as body fat. My second source, Jie Kang, gives a range of 0-5%. Thus, unless you have such fine control over your metabolism that you can guarantee that you will burn every molecule of dietary fat as it enters your bloodstream, you will incur the same cost of deposition while hiking, which is zero, but, in the process, you will have reduced its energy content/gram by ~30 calories(see below, last paragraph). The cost of fat synthesis from carbs and protein is another matter entirely, very expensive energy wise, and our respective sources all recommend ingesting dietary fat if gaining body fat is the goal.

"As to Hufeza's statement that that loss of energy doesn't count because you took that loss in the past. Well, that's an interesting way of looking at things but sounds like Enron accounting to me. If I paid $10 for a $5 item a month ago, that fact won't be any different today. I still paid more than it was worth. Calories don't appreciate in value unless you guys know something I don't."

You're right about the cost part, even though it comes from "petty cash, IMO. But what matters to me is when the cost was incurred. If I incur the cost while sitting in front of the tube watching MMA and stuffing my face with Doritos followed by an olive oil chaser, instead of luggng the fat around in my probably bigger and heavier pack, I'll gladly take the hit to my bottom line. That, in a nutshell, is what I've been talking about across multiple posts to this thread. Yeah, I paid more but it was for a purpose and so far, I've gotten my money back plus interest.

The question I am still wrestling with is that there is a difference in the calorie content of stored vs dietary fat of just over 30 cal/oz. or 500 calories/pound. What I haven't yet figured out(and may never) is the tradeoff between the extra calories in dietary fat and larger pack size, whether or not it all gets metabolized as it is ingested, how much dietary fat I can stand to slug down in a day, etc. I'm still working through that question, but meantime, what I'm doing feels very right for me. I shaved a pound off my pack weight, for instance, which is a real obvious benefit. Interesting stuff, huh?

Definitely an interesting discussion.

I like Ryan's current method of dealing with food. He relates saving item weight to how many extra calories he can carry. For instance, on this last trip he was relating how much extra calories he could carry offset by drilling holes in his shoes. That could've been for show, but knowing Ryan, there was some truth to it. He never mentioned fattening up before the trip.

"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."

Hi Laurie,

I'm really glad you joined in this discussion. It was veering off in a pretty esoteric direction and, ideally, what should come out it is a range of concerns and options for addressing them. That way, people can evaluate the full range of choices, according to their individual preferences and goals. Thanks for contributing a more balanced middle way to keep us geeks from going off too far into the wild blue yonder. :-)

"He never mentioned fattening up before the trip."

He probably didn't think it was worth it. Only he knows for sure and, so far, he ain't talkin'. It would be interesting to have him weigh in on the subject. He certainly has a wealth of knowledge, that's for sure. Roman and Jason, too.

I have to agree there Tom. After all, we all have differing opinions and ways of approaching our research.

When I first entered into writing about trail food I consulted nutritionists (some specifically involved in sports nutrition), professors and other experts including thru-hikers and other cookbook authors. It's an interesting journey and as much I as don't agree with or understand the thinking behind some of what is being posted (for my own hikes especially - long story there)... it's interesting to learn about the other points of view and I appreciate the education of it all.

Yes sir... middle of the road - that's me. Plus I'd rather carry it in a pack than on my body (lol - I've already done the latter - no fun). Not to mention you guys lost me with the math... I create... I have Bryan to calculate... lol.

"it's interesting to learn about the other points of view and I appreciate the education of it all."

Yup. I hope everybody else feels more or less the same way.

"What will happen to me with the calorie deficiency?"

Well one possibility, depending on your exertion level, is that the lack of calories will initiate the consumption of muscle. This can severely stress your kidneys as you break down that protein.

I just completed an 11 day JMT, and looking at the food left over, I did it on about 2500 calories a day. I lost over 12 pounds, and I had/have plenty of body fat. (This was Not supposed to be a weight-loss program, I just wasn't paying attention.)

For various reasons I just had a renal function test performed, and low and behold, I'm about 75% below 'Normal Low'. My Doc says to forgo a 140 mile hike planned for the first week in August. Dropping another 15% could have serious long term consequence.

Was I this low before the JMT? - Don't know.
Has this happen on previous hard efforts? - Don't know.

So, if you are still considering 1300 calories a day, I suggest testing before and after in order to monitor the impact. Drink Lots of water. And avoid ibuprophen and naproxen.

UL is good and as most people here will agree only as good as you are good with it. In other words if you're fine sleeping under a foil blanket - sweet. If you want a tent, pad, and a bag you will not be happy sleeping under tin foil for 10 days.

I for one like food and backpack for recreation meaning recreation meaning enjoyment. So to a certain point I am comfort driven. By that I mean I'm not doing Vietnam era SOG - poo hit the fan and I'm humping out with full load out for 10 days with no food type trips.

I can afford to bring a few extra pounds of food with me and I will. In fact I usually bring more to account for getting injured, lost, or going with a mooch.

Don't be the d-bag that didn't bring enough food. This will end in one of the following ways - you mooch food and people will look down on you. or You're too proud to mooch and you suffer ultimately slowing down the group and potentially getting hurt.

Please don't take my post in the wrong way. I mean well and I'm glad you asked people here for advice since now you can adapt and overcome.

>> I've been hoping you two would join this discussion at some point.

Way to put us on the spot, there, Tom. There's a reason I was avoiding it. The best point I can probably make is that this is a more complex question than almost anyone here thinks it is. To give an intelligent answer regarding your calculations back on page 1 I'd probably have to sequester myself in my office on the Ovid Gateway for a week or so to read up a bit.

You see, my nutrition classes had titles such as "Nutritional Support in the Critically Ill", so if you are bedridden and on a ventilator with 75% TBSA burns and need calories- I'm your man. I can bust out the Harris-Benedict Formula with the best of them, and produce orders for appropriate TPN, but what this discussion really needs is input from an exercise physiologist. And I seem to recall that we've actually got one around here, somewhere... :o)

That said, I will point out that the purpose of fat is to store calories. Being burned for energy during starvation is what fat is FOR. But the problem is that starvation physiology does other weird things, and it is difficult to avoid losing lean mass even if you are getting 100% of your (inadequate) calories from protein. Taking in as much as 1300 calories, however, doesn't qualify as 'starvation' as I am used to defining it. It is just under-feeding, and 10 days of it shouldn't HARM a healthy person. Also, I'm not used to worrying about how much energy it takes to use stored fat vs consumed fat, because if a patient is using stored fat then I'm doing my job very poorly. An ICU stay is not the time to go on a diet!

Heck, I could talk in circles forever. That's why hospitals have so many nutritionists on staff. :o)

Suffice to say, I can make sure someone isn't over- or under-fed during all sorts of metabolic stresses, but hiking isn't one of them and figuring out this kind of exercise physiology would take me some time and a lot of reading.

But I can tell you that hiking on 1300 calories a day will NOT be fun. Shed weight elsewhere, unless your whole thing is that enduro hiking scene. Because for some people part of the fun IS going as fast and light as possible, and enduring a bit of discomfort to do it.

Edited by acrosome on 07/25/2009 04:09:55 MDT.

Dean... I have to agree with your last paragraph and also it would be great to hear from the exercise physiologist.

After this thread started I spoke with some of my contacts in the nutrition profession (specifically sports nutrition). Not one thought this approach of bulking up and starving was a good idea from a health perspective. Then again, I can well imagine what they would say about a diet of Ramen... lol.

note: edited to fix a missing word

Edited by Laurie_Ann on 07/25/2009 08:47:16 MDT.

Tom, sorry I didn't see your post. Your original post to the OP looks okay to me. I don't recommend someone eat 1,300 cal/day when they weigh 177 lb and will be at way more than a 1,000 cal/day deficit. Like Dean says, he will likely be uncomfortable. I like to refer to "Pack Light, Eat Right" for good info.

http://thru-hiker.com/articles/pack_light_eat_right.php

"Way to put us on the spot, there, Tom."

Heh heh. Gawd, how I love to see a doc twisting in the wind. :))
But, seriously, you put your finger right on the key to further progress, i.e., smoking our resident exercise physiologist(s) out of the bushes. As you said, you are used to dealing with people whose last concern in the world is how to get by on minimal ingested calories/day in the mountains. I was hoping Richard Niseley would have weighed in by now. He's as close as I've seen to the real deal so far and, as they say: In the land of the blind, the one eyed man is king.

"Tom, sorry I didn't see your post. Your original post to the OP looks okay to me. I don't recommend someone eat 1,300 cal/day when they weigh 177 lb and will be at way more than a 1,000 cal/day deficit. Like Dean says, he will likely be uncomfortable. I like to refer to "Pack Light, Eat Right" for good info."

John,
I wouldn't really recommend it to most people, either. It's sort of the dietary equivalent of cutting half the handle off your toothbrush. Not always enjoyable, possibly not healthy(yet to be determined), and definitely not gourmet. This responses in this thread have caused me to examine, yet again, what led me off in this direction. All I can say at this point is that it has worked very well for me and, for reasons unknown to me, gives me a lot of enjoyment. Good mental exercise, if nothing else, I guess.