Diet for High Mileage Long Hikes
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Randy Brissey
(rbrissey) - M

Locale: Redondo Beach, CA
Inetrvals etc, on 02/18/2006 11:24:53 MST Print View

Paul,

Training at a high heart rate ends up being counter-productive (I was teaching this subject last week).

I usually relate to training in 4 heartrate zones. The first (lowest) I call the fat burning zone......wightloss without cardiovascular training. The second I call the green zone.....aerobic training......being able to carry on a conversation without gasping. THe third I call the blue zone (place where competition levels are found) and the last the red zone.....intervals-hell!

As long as a person stayed in the green zone fitness increased until to reach that theoretical maximum. The third level of HR (blue zone) which is around the AT is a problem. It is too hard to boosting aerobic effciency. It is difficult to recover from an extended workout here but at the same time it is too easy for full interval effects.

The problem when I deal with student jocks is that the easy days are too hard and the hard days are too easy. Students are working too hard and they burnout on their sports.

I remember an important point that a Race Across America competitor relayed to me. He said that the most important place to save and utilize energy stores were for climbing hills (passes). Here the differences between fitnesses of competitors is magnified the most.

Randy

cary bertoncini
(cbert) - F

Locale: N. California
I thought lance did more LSD on 02/18/2006 11:40:17 MST Print View

type training than was considered the norm?

I read somewhere that during off season he did considerable volumes (more than most) of slower paced cycling, rather than a lot of VO2 stuff.

Was he doing extreme periodization? Lotsa lotsa base work, then lotsa V02 stuff closer to race time?

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
How to optimize pack weight and diet on 02/18/2006 13:10:03 MST Print View

In reference to table (http://www.ultracycling.com/nutrition/calories.html) graciously provided by Anonymous, I have two comments about the 20-50% VO2 max range ratio of CHO/fat burned.

1)For a credible cycling reference, Chris Carmichael’s (Lance Armstrong’s coach) book titled, “Food for Fitness”, page 29. He says, “The numbers presented below are approximate values and ranges based on what I have seen in more than 15 years of coaching athletes…".His numbers match the Ultracycling article except that he broke the VO2 max 20-50% range into two segments of 20-35% and 35-50%. I have added his ratio numbers below the Ultracycling table numbers for 20-50%.

Approximate Sources of Energy While Riding
% of VO2 max CHO/Fat
20-50% about 50/50

20-35% about 30/70
35-50% about 50/50

60% about 60/40
70% about 70/30
80% about 80/20
90% 90-100% CHO.

2) In my initial post on this subject, I estimated that Ryan could accomplish his distance and time goals while maintaining a hiking pace of about 5 METs. At 5 METS his % of max heart rate would in the range of 60%. This equates to a VO2 max number of approximately 35%. VO2 max is correlated with the % of max heart by the formula %VO2 Max = (%MHR – 37) / .64. By staying at or below this pace, he will primarily burn fat rather than CHO. This has the benefits that his pack weight would be the lowest possible, since calorie density is optimized, and he will optimally sustain his body’s needs. Randy Brissey clearly pointed out the dramatic difference in Ryan’s potential pack weight using this approach.

Edited by richard295 on 02/19/2006 15:26:12 MST.

Ryan Jordan
(ryan) - BPL Staff - MLife

Locale: Greater Yellowstone
Re: How to optimize pack weight and diet on 02/21/2006 20:51:43 MST Print View

Re-read all the posts, in the context of some other research I've been reading.

Specifically related to the role of carbs, fat, and protein during exercise.

It seems to me that the first few hours of exercise rely primarily upon glycogen stores in the muscles for energy. Supplementing these stores (since utilization of them is not 100%) with a small amount of complex carbs with a high glycemic index (so they are utilized rapidly) is the way to go.

I've also found that complex carbs can be absorbed at a higher caloric density than simple carbs. It seems that you can only supply your body with so much in the way of simple sugars. It simply cannot process them fast enough, and eventually, leads to gastric distress if you try to overfuel yourself with higher concentrations of them. So if you're bonking, eating simple sugars will raise your blood sugar, but will also cause it to dive when it's done. Seems like the ideal energy gel should have complex carbs with a high glycemic index, to address the bonk. Better: a steady diet of complex carbs to avoid the whole situation?

As for fat "burning" during exercise, I found no evidence that you gained much energy by, say, just eating butter. Yes, you were burning fat, but it seems that the fat being burned comes primarily from your fat stores, not the fat you ingest. And this is where I am confused, so a question:

Q: is there immediate benefit from eating fatty foods, in terms of grabbing energy from them during active exercise at say, 50-65% of VO2max?

Where it really gets interesting from a long distance perspective is what to do immediately upon arrival to camp in terms of nutrition. Replenishing glycogen stores when the enzymatic engine for doing so is cranked up seems vital. I've read that the "window" for doing this ranges anywhere from 30 minutes to 2 hours and seems to be somewhat dependent on the amount of excess post-exercise oxygen that you've accumulated (EPOC, which is a function of intensity and duration). Glycogen seems best replenished (without causing gastric distress) by - again - complex carbs with a high glycemic index. Of course, some protein is important in this window as well to replenish amino acids that were cannibalized during the activity.

Finally, the name of this game is your ability to stave off the inevitable degradation of your body for as long as possible. In an "event" like this, you are probably entering Day 0 at your peak, and it's all downhill from there.

There is absolutely no evidence that an unsupported long distance event of any length near the limits of one's endurance capacity can be anything but a degradative effort.

Which again, begs the question.

How far can a hiker go, unsupported?

Frank Ramos
(frprovis) - F
one more thing about nutrition on 02/22/2006 00:05:32 MST Print View

If my memory of physiology is correct, the brain runs only on glucose from the bloodstream, which must be supplied by the liver. If the liver runs out of glycogen stores, then it has to begin converting protein to glucose. At first, the liver will use dietary protein for this. I believe the liver stores about 3 lbs of dietary protein that is normally intended for use by the cells, but which can be converted to glucose if necessary. Once that protein is exhausted, the body must begin destroying muscles. The brain must get glucose regardless of the expense to the rest of the body. I forget exactly how many calories of glucose the brain needs per day. Probably about 600, which is enormous in comparison with other animals.

In order to avoid destroying muscle too fast, it is thus essential both to walk slow and thus allow the muscles to burn mostly fat, but also to eat enough carbohydrates and proteins to provide the brain with glucose.

I would guess that a half-pound of oats per day would be sufficient to prevent rapid loss of muscle, but a pound a day would be much better. A normal man weighing 165 lbs, and neither very fat nor very lean, should be able to go at least a couple of months on this amount of food, slowly but surely losing all his fat and some of his muscle. A pound of oats would provide about 1700 calories, mostly complex carbs but also a good amount of protein and fat and also some fiber. Bulgar wheat, buckwheat kasha, rolled wheat and rolled rye are other good choices from the natural foods stores. All of these grains can be eaten uncooked. If you are really planning to hike in Alaska in the early summer, you will definitely want to be able to prepare food inside your tent to avoid bugs, and so uncooked food is a good way to go. Uncooked grains have very little smell and so won't attract bears. Contrast with butter, which even I can smell from a block away once it starts to warm up. I would imagine a bear could smell warm butter from several miles downwind. And don't forget some light salt (50/50 mixture of potassium chloride and sodium chloride) and vitamin pills.

And another thing. Ignore all this idiotic advice about variety and palatability. You want your food to be as boring as possible so you aren't tempted to overeat. Boring, but not disgusting. Oats with a little salt is just that. Whatever you do, don't bring along raisins and nuts and other stuff to make the oats taste better, because then you will have a very hard time controlling yourself from eating more than a pound a day, so you will run out sooner. And once you run out of food, the only way to supply the brain with glucose is by destroying muscle.

I have no evidence for the claim about being able to walk for months on just a pound of oatmeal a day, other than my undrestanding of what humans have traditionally endured. Going an entire winter on a small amount of wheat per day, and being forced to plow the soil and do other hard work with this tiny amount of fuel, is actually a very common story in human history.

Edited by frprovis on 02/22/2006 00:24:39 MST.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
How to optimize pack weight and diet on 02/22/2006 01:27:44 MST Print View

The answer to your first question is No, "there is no benefit from eating fatty foods, in terms of grabbing energy from them during active exercise at say, 50-65% of VO2max?"

The answer to your second question, "How far can a hiker go, unsupported?", is 643 miles carrying 40 lbs of the correct food at 44% of VO2 max.

Your body can only store about 1,500 – 2,000 C of CHO derived energy unlike fat energy which is by comparison vast. After you consume this limited CHO store you will bonk.

As an example, I am 62 yrs old, weigh 190 lbs, and have a VO2 max of 45. At a 50% of VO2 max rate, I am burning 570 C per hour and approximately 50% of the energy is coming form CHO or 285 C/hr. At this pace my CHO store will last between 5.2 and 7 hours and then I will bonk.

At a 65% of VO2 max rate, I am burning 741 C per hour and approximately 70% of the energy is coming form CHO or 519 C/hr. At this pace my CHO store will last between 2.9 and 3.9 hours and then I will bonk.

Your body can only metabolize about 350 C/hr when exercising heavily and so also needs to be factored into your exercise pace and CHO replenishment strategy.

If you stay at or below heart rate zone 2, which equates to a VO max limit of 44%, for maximum distance efficiency you could backpack up to 643 miles unsupported. At least that was what my back of the envelope calculations just yielded. Of course this is like your winter camping trip under 5 lbs equipment request post. We would rather you test the limits of survivability than us! <grin>

Using my vital statistics as an example, I consume about 500 C/h at 44% of VO2 max. 12 hours a day hiking and 2 hours of camp chores would require 7,000 activity class Cs per day. My daily basal metabolic rate is 1,730 C plus an additional 10% of the total energy Calories will be consumed in digestion (thermic processes) yielding a daily total of 9,567 for 40 miles of cross country hiking.

The daily fuel requirement, to support this activity for a sustained period, is approximately 65% fat (6,219 C = 1.8 lbs of stored fat or 1.6 lbs of dietary fat), 25% dietary CHO (2,392 C = 1.3 lb a day), and 10% dietary protein (957 C = .53 lb per day).

Up to a maximum of 10% of the average persons body weight can be dropped on a long backpacking trip without any health consequences. So for me, 19 lbs * 3,500 C = 66,500 C would be planned to be taken from my stored fat bank. At 1.8 lbs of fat required per day, I could internally supply this requirement for 19 / 1.8 = 10.6 days.

The minimum daily food value that needed to be consumed would be 1.3 CHO + .53 Prot = 1.83 lb per day for the first 10.6 days or 10.6 * 40 = 422 miles. The total food weight for this segment would be 10.6 * 1.83 = 21 lbs. After that then the daily food value necessary would be 1.6 (Dietary Fat) + 1.3 (Dietary CHO) + .53 (Dietary Prot) = 3.43 lbs per day. Assuming 40 lbs of food would be the practical limit to carry I could go another (40 -21) / 3.43 = 5.5 days, 5.5 days * 40 = 221.6 miles.

Ah ha! Ryan is a slacker! Only going 400 miles cross country when he could actually go 422 + 221.6 = 643 miles. Of course if my calculations are wrong he might starve. Arrg... Ryan be sure and double check my math and logic before trying this.

In summary, a 28% increase, from 400 miles to 643 miles is feasible by changing the VO2 max zone for your hike from your planned 50 – 65% to an average of 44%.

In my original 2/16/06 16:27:44 MST post I pointed out that you should be able to achieve your time and distance goals with an average 5 MET expenditure. My above fuel recommendation, for a 44% of VO2 max pace, conservatively yields a 7 MET allocation; 502 Cal/hr (expenditure) / 72.1 (BMR) = 7 (METs). As they say in the car mileage advertisements, "Your mileage may vary".

Edited by richard295 on 02/22/2006 06:58:50 MST.

Michael Wands
(walksoftly) - F

Locale: Piney Woods
Diet for High Mileage Long Hikes on 02/22/2006 12:12:05 MST Print View

A question for Frank Ramos:

How do you prepare these no-cook oats that you carry? My rabbits love rolled oats, but I've never really considered eating them myself.

How about the Carb grams per serving? I got a big surprise for my 50th. I was diagnosed with Type 1 Diabetes!!! This is no big deal, but it is inconvient. I used to have the option of fasting on weekend hikes, but now I have to keep my blood glucose level in a certain range.

Kevin Sawchuk
(ksawchuk) - BPL Staff - MLife

Locale: Northern California
Long Distance Meal Plan on 02/22/2006 12:12:55 MST Print View

At nearly any pace short of running you will be burning mostly fat--especially if you've trained at a similar pace. Even a 150# person who is very lean (5% body fat) has 7-8# of fat which will provide 28,000C--enough to last about 6-7 days if taken with some carbohydrate. After that you'll start burning more muscle unless caloric needs are more fully met. The story doesn't stop there: You need carbohydrate to burn this fat. When you're burning endogenous (body) fat in the first few days a small amount of carbohydrate --100-300 C/hour--is probably enough. You can't store much carbohydrate and fat can't be converted to carbohydrate.

After the first few days you'll need more calories including a good mix of fat, carbohydrate, and protein. At this point you should get close to as many calories as you need or your performance will suffer. It's probably better to more evenly distribute you caloric intake than to wait to start eating until the 5th day. However if you're only on a <7 day trip you may be able to scrimp a bit.

Liquids are easier to take than solids but on a long trip I find that variety really helps you keep up the calorie intake. I personally don't think eating only cold meals is worth the weight savings--for me it's just unappealing. I use a lot of drinks in the day (Balance, Acceleraid, Cytomax) but want a more solid meal (cooked) at night and some solid food in the daytime. This is a personal preference--if you can tolerate liquids for 20 days go for it!

Frank Ramos
(frprovis) - F
no-cook oats on 02/22/2006 13:04:27 MST Print View

How do you prepare these no-cook oats that you carry? My rabbits love rolled oats, but I've never really considered eating them myself.

You just pour some regular 5-minute rolled oats in a bowl with some water, and start eating them. You can also add salt, powdered milk and dried fruit to the mixture if you want. The body digests all this food just fine. 1-minute oats is also okay, though I prefer the texture of 5-minute oats. I would avoid instant oats since I don't trust foods which have been highly processed.

You can do the same thing with bulgar wheat, buckwheat kasha and rolled wheat and rolled rye. Wheat is the most nutritious of the common grains, but I prefer the taste of oats. All these grains have essentially the same number of calories per pound (about 1700).

Couscous is another possibility, but a poor choice. Bulgar wheat is wheat berries which have been steamed until they burst open, then dried, and is thus the entire wheat berry. The similar-looking couscous is refined flour which has been rolled together into tiny pellets, then steamed to pre-cook it, then dried. Couscous has the same lack of fiber and minerals as white bread or white flour pasta.

Type I or Type II diabetes? Regardless, uncooked 5 minutes rolled oats has a lower glycemic index than cooked 5 minutes rolled oats, which in turn is less than 1-minute oats, which is less than instant oats. The lack of cooking and the texture of the 5-minutes oats seems to slow down the digestion, at least in my experience. I can eat a big bowl of uncooked oats without feeling any blood sugar surge. With couscous, on the other hand, I would feel a blood sugar surge.

Edited by frprovis on 02/22/2006 14:08:21 MST.

Bill Cooper
(bwcooper) - MLife
Re: How to optimize pack weight and diet on 02/22/2006 17:42:39 MST Print View

Nisley's prior post was fascinating. But I thought his estimate of 9,567 kcal per day was high, so I took a somewhat different approach with different assumptions to calculate Ryan's energy requirements for a 40 mile day. Whallah! I came up with almost the same number. Ryan is going to be one tired dog!

BTW, an average hiker can use the this method to calculate -approximate- caloric needs for a hike. Guess-timates also work.

Nisley used MET values in his calculations. These are often used in population studies and provide a convenient shorthand for estimating caloric expenditures for different activities. Tables of MET values are available in texts and on the web; one extensive table is linked off this page: http://prevention.sph.sc.edu/tools/compendium.htm .

The values are derived from laboratory studies and inferences, but they're only estimates for real world conditions which vary with body build, conditioning, environment, etc. A MET (Metabolic Equivalent) is defined as an energy expenditure of 1 kcal/kg/hour. This is roughly equivalent to the energy cost of sitting quietly, i.e., your approximate basal metabolic rate (BMR).

Since MET values for different activities include this 1 MET base, one should not add the day's non-resting energy expenditures to the BMR, only the differences. In other words, an activity such as "walking 4 mph on level ground that uses 'x' METs" is actually using only an additional "x-1" METs over the BMR. So to calculate the day's energy costs, take the basal metabolic expenditure and add the sum of the day's activities each calculated at an adjusted rate.

Energy expenditure is correlated with body mass for most activities. Strictly speaking, you would plug in a different weight for camp chores than for when carrying a pack. So if Ryan himself weighs 170 pounds and started with a 50 lb pack (10 lb base load and 40 lbs of food), his exertion at the beginning of the hike would be based on a 220 lb weight. Assuming linear food consumption, we can use an average pack weight of 30 lbs and a total skin out weight of 200 lbs (nice round number) or 91 kg (not so nice).

On a side note, walking efficiency isn't a flat curve, i.e., you typically expend more energy per mile the faster you walk (indeed, there's only one physical activity that has a fairly flat efficiency curve and that's running). If I remember correctly, the most energy efficient walking speed for a person of moderate build is somewhere around 2.2 mph. As a practical matter, the overall most efficient speed for a long distance hike is higher since there's a daily basal metabolic cost just to be out there. It would be interesting to calculate some speed and consumption curves and see where they intersect and whether this method jives with the VO2 max calculations.

Finally, it takes "physical" work to lift an object against gravity (walking doesn't do much work in the "physics" sense). Though my calculations may be off (correct me), it requires about 70 kcal to lift a 200 lb. body 1000 ft. If we assume 25% metabolic efficiency, that translates to 280 kcal of food needed per thousand feet of climb. (BTW, you don't necessarily gain it back going down - steep descents are more energy expensive than walking flat but we'll neglect downhills).

Assume Ryan covers half of a 40 mile day walking on fairly unobstructed surfaces and half the distance bushwacking (no stopping to swat mosquitoes!).

If Ryan averaged 3.5 mph on the unobstructed surfaces, the approximate MET value would be about 4. Let's add an additional 1 MET since the surfaces aren't smooth for a total of 5 METs. Ryan's speed will fall while bushwacking but the work is harder. Let's say he makes 2.5 mph (boy this dude's working) and assume a 7 MET rate for those 20 miles. We don't know where Ryan's going but let's assume 3500 vertical feet of climbing each day.

The calculations go as follows using MET rates corrected for the subsumed BMR, i.e., reduced by one:

Unobstructed walking:
20 miles at 3.5 mph = 5.7 hrs ; 4 kcal x 91 (kg) x 5.7 (hrs) = 2075 kcal

Bushwacking:
20 miles at 2.5 mph = 8.0 hrs ; 6 kcal x 91 (kg) x 8.0 (hrs) = 4368 kcal

Climbing:
3.5 (thousand ft) x 280 kcal = 980 kcal

Camp chores (housework):
(2.5 - 1) kcal x 77 (kg - no pack!) x 1.0 (hrs) = 115 kcal

Basal metabolism:
1750 kcal

Total: 9288 kcal

Ryan hopefully will take daily self portraits so we can see how haggard he gets!

Ryan Faulkner
(ryanf) - F

Locale: Mid atlantic, No. Cal
Re: no-cook oats on 02/22/2006 17:45:34 MST Print View

I just made up an interesting breakfast mixture.

in a plastic bag I put in a half cup of irish oatmeal, or whole oats, and a half cup of raisins and a quarter cup mashed almonds, including calories from fat, this mixture is just less than 500 calories and with the raisins, it dosent taste half bad, even when eaten dry, and if eaten with a natures valley granola bar, you have a breakfast at almost 700 calories.

sounds good to me

Edited by ryanf on 02/22/2006 18:34:04 MST.

Frank Ramos
(frprovis) - F
diet for high mileage long hikes on 02/23/2006 18:55:30 MST Print View

In looking back, I notice I never actually answered Ryan's final question as to how far a hiker can walk unsupported. Obviously, a precise answer is impossible. But certainly we can make some reasonable estimates.

Instead of 40 miles/day, let's back off to 20 miles/day. That allows for 25 miles on most days, but a few short days in case of bad weather or physical or mental exhaustion. 25 miles at 2.5 miles/hour means 10 hours of walking, which is quite a lot. Anything more than that and I think the body or mind or both are likely to get stressed out, opening the door to injuries and illnesses.

Instead of these ridiculous estimates of 6000, 7000, or even 9000 calories/day (who will be the first to argue for 10,000?), let us assume a more reasonable 5200/day. The military estimates a combat soldier needs 4500, so we are being quite generous, in my opinion. One of the posters arguing for 9000 calories/day concluded with a most apt remark about "your mileage may vary". Indeed it may. If you drive a car with one foot pressing on the accelearator and the other foot pressing on the brake, then your mileage may drop under 1 mpg, while your brakes are destroyed in the process. It is certainly possible to do something analogous with our bodies, but I'm going to assume we're a little smarter than that.

Now assume our hiker normally weighs 165 pounds, with 15% body fat, of which 5% is essential and 10% expendable. Let us further assume our hiker bulks up beforehand to 180 lbs. I think I can speak for the majority of Americans that adding 15 pounds is not too difficult. (Yes, there are some exceptions to this rule. Some people simply can't pack on extra weight.) So our hiker will have more than 30 pounds of fat he can afford to burn off.

Now assume our hiker carries a base pack weight of 12 pounds, plus 3 pounds of water, plus 30 pounds of a mixture of plain rolled oats and non-fat powdered milk, so his beginning pack weight is 45 pounds, which is doable even with most ultralight packs, considering that this initial weight will be dropping rapidly and the average weight will be under 30 lbs. Included in the 12 pound base weight is some light salt (50/50 potassium chloride, sodium chloride) and some vitamin pills.

The oats/milk mixture gives about 1700 calories/pound. This includes at least 50 grams of protein and possibly much more, depending on the percentage of milk, which is adequate protein. The oats/milk mixiture does not contain adequate vitamins, especially vitamin C, and thus must be supplemented. The body fat gives about 3500 calories/pound. If the hiker eats a pound of oats-milk/day and burns a pound of fat/day, then he will be able to go 30 days burning 5200 calories/day, without needing to burn any muscle. At 20 miles/day, our hiker can thus walk about 600 miles unsupported before he needs to burn off muscle. At the end of this 600 miles, our hiker will weigh about 150 pounds and look lean, but hardly unhealthy.

Speaking from personal experience, the weight fluctuations described above are nothing extreme. I recall weighing about 175 pounds playing football in high school but 150 pounds when running track. I weighed over 185 pounds at one point during my thirties. My current weight is about 165 pounds. This is for a man who is 5'11" tall and average build.

The estimate of 5200 calories/day was just pulled from the air, and I think it is high. The reason I think this is my reading about how our ancestors lived and how primitive peoples live today. I think even 4000 calories/day is generous. By walking gracefull, so as to avoid wasting energy, it might well be possible to walk 20 miles/day without burning any more energy than we burn when lying about the house doing nothing. Thus it might well be possible to walk two months or 1200 miles unsupported.

The interest in this discussion is not unsurprising, nor are some of the hysterical responses, which are very reminiscent of the hysterical reactions to the early proponents of lightweight backpacking. "Tarps are never going to work!" or "It's suicide to hike in the mountains without heavy boots!" Remember all that? Those of us who were once heavyweight hikers probably reacted thus ourselves initially when we heard of other people hiking with 10 pound base weights. No one likes to change habits and relearn everything from scratch or be forced to replace one set of expensive gear with a new set. But after we calm down, we realize that the change is for the best.

In my opinion, nutrition is the next great frontier in long-distance lightweight hiking. No, the average hiker does not need 9000 calories/day. And no, hikers do not need to cook their food nor will they much care after the first few days whether the food is cooked or not, or spicy or not (though salty-tasting may be highly desireable). All that matters is that the food be nutritious.

What the above example shows is that most long-distance hikers are probably carrying way more food than they really need. Instead of bringing along olive oil and other fats, why not just carry the fat on our bodies and burn it off as needed? During periodic town stops, eat heavily so as to rebuild the fat reserves. Most long-distance hikers actually end up doing exactly this, though not intentionally and thus probably not optimally. In particular, many hikers tend to rush through the towns. What they should do instead is linger a while, at least one day and perhaps two, so as to pack in as many fattening meals as possible before setting off on the trail again. The time lost during the town stops can be regained by walking longer on the hiking days, due to carrying a much lighter pack and not needing to spend so much time preparing and eating meals.

Edited by frprovis on 02/23/2006 19:03:21 MST.

Roger Caffin
(rcaffin) - BPL Staff - MLife

Locale: Wollemi & Kosciusko NPs, Europe
Simplicity on 03/08/2006 02:41:48 MST Print View

All this business of special food drinks and diets etc seems a complete waste of time (except for BillF). I predict 99.9% of the population would very quickly come to HATE the drinks!

Antarctica: a quite well-known diet there consists of mashed potato and butter (or lard). That's it for the day! I think the typical dehi spud has salt in it, as does the butter. From this you get carbo and fats. Strangely enough, Antarctic explorers who have used this diet seemed happy with it. (Yeah, I would like a little more variety, but ...)

My wife and I have done a fair few hard trips up to 2 months long. We take our typical walking diet: muesli for breakfast, biscuits, butter, jam etc for lunch, soup and then pasta/rice stew for dinner. No, we have never got tired of it - partly because I can keep ringing the changes on the dinners. Oh yes - and I have this little bag of herbs, spices, curries etc!)

We would normally take about 680 g per day for my wife and 750 g per day for me - I'm 64 kg and slightly larger than my wife. These quantities will do fine per day for up to about two weeks. After that, when we were pushing it hard (like 35 km/day cross country) our food consumption per day started to rise. At the end of 4 weeks we were eating 150% of normal, but we WERE really pushing it. Otherwise we see a small increase per day - maybe 25% but no more, after a few weeks.

How far can you go unsupported? Read
Nanda Devi by Shipman & Tilman
The Worst Journey in the World by Cherry-Garrard
Shackleton's Forgotten Men by Lennard Bickel
The Long walk by Slavomir Rawicz
etc

Cheers
Roger Caffin

Al Shaver
(Al_T.Tude) - F - M

Locale: High Sierra and CA Central Coast
Fat V Carb on 05/10/2006 22:25:10 MDT Print View

On a 12 day un-resupplied 208 mile JMT hike I consumed 2 quarts of safflower oil from a platypus bladder. This is 16,128 Calories or 1344 Calories/day from pure oil (100% fat). I supplemented this with 4 Clif bars, 5 quarts Gatorade, beef jerky, hot chocolate and instant noodle soup for a total of 3854 calories/day. This worked well for me.

This summer (or maybe fall considering the heavy Sierran snowpack) I will be attempting to set a new un-resupplied, un-supported speed record on the JMT. To do so will require a 5-1/4 day trip length or 40 miles/day.

I considered upping my fat percentage in my diet to keep pack weight down. I figure with 4000 Calories of oil/day, no other food and Nuun electrolyte tablets, I could start the 5-1/4 day trip with a Fully Loaded 11.5 lb. pack.

However, on a 5-1/4 day pace I'll be running longer and harder than my 12 day pace. Based on previous posts I'll be better off with the predominantly carbohydrate Accelerade (maybe I'll toss in the occasional jerky treat).

8.6lbs. Accelerade yields 47.25 quarts mixed beverage. At 2.3, 350 Calorie quarts/10 miles (or 4.4 miles/quart), I'll consume 9 quarts (3150 calories)/day at a 5-1/4 day pace. If I'm able to hold a 4 day pace (52 miles/day), my allowance goes up to 11.8 quarts Accelerade (4134 Calories)/day. Adding an ounce of jerky/10 miles bumps my complete starting pack weight up to 16 lbs. Going from fat to predominantly carbs increases my starting pack weight by more than 4-1/2 lbs.

I expect to make up my caloric deficeit by consuming body fat and muscle. In an event this short I think that's feasable without serious performance losses.

On a longer event like Dr.J's this stategy may not be practical. Monotony, lack of solid food and muscle wasting will likely need to be addressed. At the lower exercise rates of a longer trip I would go back to a high fat diet for weight savings. BTW butter has only 79% of the caloric density of pure fat (such as vegetable oil). Oil keeps better and weighs less/Calorie. Also, I discovered on a Trans-Sierran ski trip that while vegetable oil stays liquid at freezing temperatures, light olive oil congeals-which can prompt some interesting locations on the body to place one's oil flask to stimulate the melting process.

Frank brings up some interesting points regarding our ancestral dietary habits which I tend to agree with. I think in the long run our "feast or famine" developed genes will override all the nutritional math we choose to conjure. I think something in the 1000 mile range is feasible before the body loses the ability to locomote, or expires. Amazing feats of human powered transit are accomplished every day all over the world by nomadic peoples and refugees.

I do question the idea of "bulking up" on body fat before a trip. If we only get to use 3500 Calories of each lb. of body fat, versus 4000 Calories per ingested lb. wouldn't it be preferable to put it in our packs? Also, it's impossible to cache body weight for round trips, side excursions or loop trails. Even hunting for wood, water, game or campsites requires you to drag this ballast around rather than cacheing it.

"The New Laurel's Kitchen" has a very informative section on nutrition. In the "Protein" section it states that adults with adequate caloric intake need very little protein-just for maintenance. However, with diets low in calories relative to caloric output the body scavenges all food sources and starts burning protein for energy rather than using it to replace tissue. This means that in this situation the percentage of protein in your diet must be substatially increased to discourage muscle wasting and other tissue degredation. This leans me toward a high fat, moderate protein diet-maybe 70%calories from fat/30%from protein?

Richard,
When you give % of nutrients for various exercise profiles, are these by calorie, as I have given, or by weight?

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Fat V Carb on 05/10/2006 22:47:34 MDT Print View

Al,

Calories as you have given.

To optimally dial in your on-the-trail-diet prior to the attempt you can go to a physiology lab and have your RER curve (ratios of fat/CHO burned at different %s of VO2max) measured for about $200.

Alternatively your past experience should serve as a reasonable guide.

Richard

Edited by richard295 on 05/10/2006 23:13:49 MDT.

paul johnson
(pj) - F

Locale: LazyBoy in my Den - miss the forest
Re: Fat V Carb on 05/11/2006 01:47:46 MDT Print View

[my apologies, just can't recall the journal article details with enough certainty to leave this post intact.]

Edited by pj on 05/11/2006 03:35:33 MDT.

Al Shaver
(Al_T.Tude) - F - M

Locale: High Sierra and CA Central Coast
RER on 05/13/2006 23:09:40 MDT Print View

Richard,
Thanks for the RER measurement tip. I wasn't aware of that option.
Al

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
RER on 05/14/2006 08:35:18 MDT Print View

Al,

You are quite welcome. If you have that test done also talk to them about the RER drift with time.

For example assume you test that you are burning an equal amount of fat / CHO at 65% of VO2max. Normally the fat % will increase in hours 2 and 3 and then stabilize. Ask them to provide you their forecasted drift numbers also.

Edited by richard295 on 05/14/2006 08:36:35 MDT.

Jay McCombs
(jmccombs) - MLife

Locale: Southwest
Re: Re: How to optimize pack weight and diet on 05/22/2006 07:25:54 MDT Print View

Ryan. Do not underestimate the importance of protein in your diet. You need to base your diet around your protein needs and then everything else is less important from there. Get 1-1.5g of protein per every pound of bodyweight. Protein is by far the most important nutrient for maintaining lean mass and health in general.

At the end of the day its a simple equation. Calories in must equal calories out otherwise your going to drop weight and energy and hamper recovery which will increase your chances of being injured. You need to figure out how long you can maintain a hypocaloric diet and still function at a high level of activity. Start eating about 12x your bodyweight in calories a day and see how it makes you feel. After 3-4 days of this go out for a jog. You might discover you're going to have to budget more weight for food.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
How to optimize pack weight on 05/22/2006 08:10:27 MDT Print View

Jay,
I believe you meat to say “Get 1-1.5g of protein per every kg…” and not “Get 1-1.5g of protein per every pound…”. Note that 1 kg = 2.2 lbs. Lance Armstrong and his team mates consumed approximately 1.5 g / kg of protein during last years Tour De France.

Edited by richard295 on 05/22/2006 08:12:32 MDT.