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 The Ideal Fuel Mixture for Optimum Performance

 For Shorter Distance hikers:

 For Long Distance hikers:

Half the fat that you burn is from storage, half is supplied by the food you eat. To minimize pack weight, choose a higher fat menu. A 50-35-15 Diet on the trail is reasonable:

If you are maintaining or losing weight, the fat you are eating is not likely to accumulate on artery walls ("atherogenesis"). Fat is more likely to go to where it's needed--to fuel the working heart and skeletal muscle.

A higher fat diet not only provides the fuel your muscles are using, it weighs less (about 20% less) than a high carbohydrate diet (70-15-15). Unadjusted for water, 3000 Calories will weigh 1.5 pounds/day on a 70-15-15 diet. (That's a diet composed of 70% carbohydrate, 15% fat and 15% protein). With a 50-35-15 diet (50% carbohydrate, 35% fat, 15% protein), 3000 Calories will weigh only 1.3 pounds. Since carbohydrates and protein are more likely to bind water, the difference will be even greater when corrected for water weight (approximately 20% difference).

What about the 30:40:30 diet?
This diet abuses one of our precious planetary resources--protein. Millions of children around the world are starving for protein and there is no justification for consuming excessive amounts of protein. Your body will just remove the extra nitrogen and treat it like a carbohydrate. But you have to drink extra water to get rid of the nitrogen waste. Double whammy, considering you are treating and carrying every mouthful of liquid.

How to compute % Calories from fat
Aim for at or below 30% if you are a weekend hiker, above 35% if you are a long distance /long duration hiker.To Calculate:

(#grams fat)(9Cal/g)100 divided by (Total Cal) = % Calories from fat For example, a package of instant Quaker oatmeal lists 94 Cal and 2.0 g fat per serving.
Calculate: (2.0g fat)(9Cal/g)100 divided by (94 Cal) = 19% fat -- Fine for a short-term hiker Notice: If you eat sugar, hormones and enzymes alike adjust to burn sugar and will lock fat in storage. Simply stated: Eat fat, burn fat. Eat sugar, burn sugar. If you want to burn fat, avoid sugar. Instead, eat fat mixed with protein and complex carbohydrates.


Depending on the intensity and duration of exercise, the ideal fuel mixture changes. Muscles engaged in long duration moderate intensity exercise burn about

When exercise intensity increases, you still burn about the same absolute amount of fat, but the increased energy demand will be met by burning more carbohydrate, so the ratio of carbohydrate to fat increases. That's why a marathon runner is more likely to deplete his/her glycogen in 2 hours of running than a long distance hiker is to deplete his/her glycogen in 6 hours of hiking. And that's why a high carbohydrate diet makes terrific sense for a runner, but may be less than ideal for a hiker. Both run the risk of depleting glycogen stores; the strategy for prevention depends on training and snacking (see Snacks).

So won't my body pull what it needs from stores?
Yes and no. Whether or not you eat the "perfect balance", the body is going to depend on its own resources to some extent. Does that mean you can eat whatever you want? Not if you want to continue going day after day after day. You need to #1) supply supplemental energy sources and #2) replace the losses from your storage depot sites.

What if I don't eat enough food?

Running low on fuel can be good news for some, bad news for others. Some desire to lose weight and intentionally reduce their food intake so that they no longer have to transport 5-10 extra pounds of spare tire/flab. Others are, intentionally or not, starving their bodies, causing their own muscles to be torn down to fuel the Energy Machine and consequently seriously impairing their own performance. How can you know the difference between a desirable weight loss and an undesirable consumption of your own body?


If you don't get enough food on the trail, you won't die--as long as you have enough water. You'll lose weight. And for most of us, that's not a problem. Backpacking is a lot like pregnancy--a healthy outcome is dependent upon being properly nourished before you start. You likely have a good supply of stored fat ready to stoke the furnace for climbing mountains and exploring canyons. Regardless of the composition of your diet, that stored fat will be called upon to contribute to the energy needs of the muscles. So you can expect to lose fat out of your adipose tissue. If it goes out faster than it comes in, you'll lose weight

If 500 Calories are coming out of fat stores each day and NOT being replaced, you'll lose about a pound a week. For most of the population that would be a desirable weight loss. But for those who are already slim and trim, you run the risk of burning off muscle, particularly if you are male. Don't purposely starve yourself. There are other ways you can trim weight off your food burden; see Savings.


 APPETITE and WEIGHT LOSS--Difference of the Sexes

You've heard it said that guys are different from gals. Regarding weight loss and fuel utilization, it is certainly true. Males are more likely to burn off muscle protein when fuel supply is limiting. Females are more likely to burn fat. When males do burn fat stores, they are more likely to lose their internal padding, whereas females lose their subdermal (surface) layer of fat. (Digression: The loss of a pound of fat IS a pound of fat; the loss of a pound of carbohydrate is really only one fourth carbohydrate (glycogen). The other 3/4 is water. The glycogen stores replete overnight, so it is easy to gain a pound or two in your sleep, as water is trapped with the glycogen.)

Back to losing fat. Whether it comes off the surface or from deep within, every hiker that has been on the trail more than a week has experienced the loss of abdominal flab and the hardening of the thighs and quads. Too bad it doesn't last, hm? Within a week off the trail, the weight is back on seeming to target around your middle. This is the proverbial "weight cycling" game that engages most of America, and you're better off if you avoid it. As you decrease your activity, your body (LPL--lipoprotein lipase, specifically) will be more efficient than ever at pulling fat from the bloodstream into the adipose cells, so your weight is likely to rebound beyond what you previously considered "normal". So use the energy stored in fat to build muscle while you're on the trail. But once off the trail, try to maintain an exercise program that will sustain your new muscles and burn off any tempting extra calories. And avoid all those high fat foods I told you it was OK to eat earlier.

 Starvation robs you twice!

If you seriously undereat day after day, (more than 1000 Calorie deficit per day), you not only deplete your glycogen stores, you also digest your own muscles. When carbohydrates stores are gone, your body takes the most "expendable" fuel available. That happens to be fat stored in adipose (first choice) and muscle protein (second choice). Tearing down your own muscle means you have less endurance; you compromise your own performance. Less muscle. Weaker body. Less miles/day. More work per mile. Agony.

Solution: know how many Calories (= pounds of food) you are likely to need to maintain stable weight or, at worst, only lose about 1 pound per week (See Snacks). Recognize that male hikers generally burn more calories than their female companions, so a marginal diet will decimate their energy reserves before that of a female. If you are losing more than a pound a week, make sure you follow the snacking strategies to provide enough carbohydrate to spare your muscle protein. If you are losing more than 3 pounds per week, expect your muscles to begin protesting. There are fewer of them doing all the work. If you are losing more than 3 pounds a week, and want to prevent it, Eat more! Hike less!

[Note to those whose weight is rapidly restored. Rehydration is the most likely cause, not muscle repletion. A few pounds lost that are instantly regained are due to water.]



(Caution: Advice for Long distance hikers, for On the Trail only. Do Not Try This At Home!)



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