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JMT Atempt Report
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Aug 10, 2007 at 11:22 am #1398050
Thanks a lot guys,
You cleared up a lot of confusion but at the
same time created a lot of questions for some
one like me.OK, so carbs are the preferred primary fuel for a multy day endurance race like the JMT.
What is the advantage, weight wise & energy
availability when needed wise, of getting those
carbs from gels vs lets say crackers, cookies, cold cereal and potato chips?
If protien is important, is it best taken at the end
of the day prior to sleep for optimum muscle recovery?
How about fat?…Calorie dense but slow to digest, therefore not an immediate source of energy, is it
better taken during the day or before sleep to allow more time for digestion?
Long distance trekkers frequently carry olive oil to
supplement their calorie needs with minimum weight. What is your opinion and how much would you recommend?
Are nuts not a good choice, even though calorie dense,
because of slow digestion and low usable energy availability?
Again all my questions are related to a multy day
endurance event.Aug 10, 2007 at 11:28 am #1398053Honorable Reinhold,
I hope I am as fit as you when I reach 60! Anyway, check out Hammer Nutritions free 70-page downloadable book on "Endurance Athlete’s Guide to Success". It is great and very informative. You can also call them and may be able to have them send you printed version of it. I printed off my computer.
Here is the link to the downloads page on their site. It is in PDF form and is the second item in the list, after their catalog:
http://www.hammernutrition.com/za/HNT?PAGE=FREEDOWNLOADS
Here is a direct link to open the PDF (large file):
http://www.hammernutrition.com/downloads/fuelinghandbook.pdf
I highly recommend it.
Aug 10, 2007 at 12:04 pm #1398056Reinhold – The major problem with crackers, cookies, and potato chips is the relative fat content which makes them hard to digest and the relatively low carb contribution. For example, the detailed breakdown on 100g of crackers is 502 C; 7.4 g of protein, 25.3 g of fat, and 61 g of carbs. 81% of your calories are from fat since fat is 9C per gram versus 4C per gram for carbs and protein.
One manufacturer of sports nutrition products has a patent on the ratio of 25% protein to 75% carbs. A series of studies showed a slight edge for this consumption pattern versus eating your protein after your day is finished. Protein takes the longest time to digest and consequently best benefits warmth when most of it is eaten in the evening.
Fat is better taken in the evening. The lower you keep your VO2max (correlated with heart rate) the more that you benefit from fat consumption. Olive oil is excellent if your objective is to pace yourself by maintaining a relatively low VO2max to achieve the maximum distance with the least weight for food.
Nuts are best for distance optimized hiking as opposed to speed optimized hiking.
Aug 10, 2007 at 5:02 pm #1398082Hey Richard,
I was waiting for you to jump in on this.
You also have to remember about how many cal/hour someone can consume.
For Michael it would be about 250 and for me about 230.
You just have to realize the needs for carbs and get the % out of what you can with the least amount of callories to sustain you so you can get the rest of the calories with protien and fat.
If you can do that while getting the amount of carbs you need you are good to go.By the way, you guys are awesome on this site.
Thank you for all of the great feed back and encouragement.Aug 11, 2007 at 2:00 pm #1398161Thanks a lot to all of you guys for the info. This is all new to me. I can see now that there is a whole new science in selecting the most suitable menu for endurance activities, not just gobbling down a lot of calories.
OK, let's say for a multiple day JMT fast pack where the hiker alternates between power walking & shuffle jogging for 20 hours a day with periodic rests, walking the ups, jogging the downs, and alternating between power walking & shuffle jogging on the straights (not as intense as racing but pushing yourself at the maximum pace that you can maintain for several days).
It seems to me that energy gels alone may not be a wise choice and 70% carbs, 15% protein, 15% fat may be more appropriate…am I correct?
Is it more advantageous from a weight and performance point of view to get those 70% carbs from energy gels or standard backpacking food like nuts, beef jerky, crackers & cheese, m & m's & snicker bars? What is the preferred combo?What about fibers in carbs, are they counted at 4 calories per gram or are they excluded when figuring available calories?
For the 30% protein and fat need, are nuts, olive oil, cheese,& beef jerky a good choice or what is the preferred combination from an available energy and weight point of view?
As you can see, it's hard to teach an old dog new tricks.JMT Reinhold
The old dogAug 14, 2007 at 6:38 pm #1398607whoa!! I was absent for some time and come back to quite a discussion!
I guess it depends on a person, which food is preferred, but in this particular application, if I had to use nuts, chips, jerky etc, it would have slowed me down significantly (stopping down to chew, time and energy it takes for the nutrients to get processed by the body), whereas gels get absorbed by the body almost instantly without any byproducts formed in the process, and there's no need to stop and catch breath when flying down the trail. All of the fats and protein I ate at longer rest stops before sleeping. This way it's easier for the body to process those when at rest, when there's bigger volume of blood available for the stomach's work. At least this is my understanding of it.Aug 14, 2007 at 8:39 pm #1398620Reinhold – You are correct; a ratio of 70/15/15 is best for a multiple day endurance event.
The preferred combo can be illustrated by the above metabolic substrate model for a 64 year old male, VO2 Max = 45, height = 5'11", and weight = 190 lbs. Assume he eats adequate carbohydrates during his conventional dinners and breakfasts resulting in starting each day with full glucose and glycogen stores of 1200C.
During a normal paced hike his heart rate averages 90 bpm. After about a half hour of walking, his body transitions to burning 86% fat (378 C/h) and 9% CHO (39 C/h). He can walk for 1200/39 or 30.8 hours without eating before he would be forced to slow down. At his pace most any balanced diet he selected would be adequate.
During a JMT fast pack his heart rate would average about 124 bpm. After about a half hour of fast packing, his body transitions to burning 36% fat (266 C/h) and 59% CHO (433 C/h). He could only fast pack for 1200/433 or 2.8 hours without eating before he would be forced to dramatically slow down. Let’s assume that he averages consuming 1 gel packet consisting of 120 C of complex CHO each 1/2 hour. He could then easily maintain his required energy levels for the required 20 hour days and replenish fat/protein while digesting conventional food during sleep. There are no conventional foods that can be digested while exercising at this pace and provide the required CHO that I am aware of.
Dietary fiber is included in total carbohydrate on food labels but it doesn't count in providing energy for a fast pack. Fiber promotes bowel regularity and helps fight some diseases. However, fiber is not a nutrient, because it is neither digested nor absorbed by the body.
Any of the food combinations you mentioned are fine for replenishing your glycogen stores, fat, and protein. Just eat any combination that provides the required totals.
Aug 14, 2007 at 11:26 pm #1398631Richard,
Just to let you know, I believe my V02 Max is now higher than what the chart is set up for.
I have been doing a great work out that racks it up quick.
Get on a treadmill at 15% grade and 3.5 mph for an hour.
This is the hardest workout I do, (and by far the best).
When I first started doing it,(last year), I would almost pass out at the end.
Now I have done it for 3 hours.
After the 1st hour your heart rate is just below 175, just below 180 for the 2nd and just below 185 for the 3rd.
It also helped to have the A/C down to 60* and the fan on me.
Talk about results though, (just had to put this in).I have to agree with Michael about the chewing.
It slowed me down a lot. After the first day, your stomach starts to reject everything you put down it.
I had to stop every time to eat, mainly because I had to drink with the food chewed to get it down.Aug 15, 2007 at 8:51 am #1398673Aaron – The chart I most recently posted is for someone who is in much older and with a much lower VO2max than you. On 1/20/07 your forum post listed your relevant values as
6'- tall
155 – lbs
34 – years old
58 – max VO2Your 1/20/07 metabolic profile, prior to your enhanced VO2max contrasted with an in-good-shape-64-year-old-man would be as follows:
In contrast to the 64 year old example, at a fast pack heart rate of 124, you would be burning 417C per hour of fat (68%) and 166C per hour of CHO (27%). Assume a 1,200 glycogen store from a conventional breakfast and dinner. I don’t have your waist measurement to calculate your % of body fat but I will assume that your are a typical athlete that can count on a reserve of up to 100,000 calories in the form of stored fatty acids. That’s enough, if you could process it all, to fuel a run from Portland, Oregon to Los Angeles, California-a distance of almost 1000 miles. In other words having enough fat for fast packing is not an issue.
You would need less than 1 gel packet per hour or less than ½ the gel packets per hour and smaller gel packets as the representative 64 year old athlete would require. The calculation is as follows:
166 CHO C per hour * 20 hrs = 3,320 CHO C per day required
1,200 C in glycogen storage from a conventional dinner
3,320 – 1,200 = 2,120 CHO C needed to consume during the day
2,120 / 20 hrs = 106 C per hour in CHO needed -
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