So how many more years do you foresee that you will be able to hike 10 miles carrying 80 pounds? Sounds to me like you're going to grind your cartiledge to dust before you turn fifty. Human bodies were not designed for such long-term extreme use. Once you're unable to maintain such a high-caloric burn, your diet will likely begin to turn on you. There are many LCers here who do no exercise, still lose weight, maintain fine muscle tone, and are healthier than a horse.

I didn't count exact grams of protein, but I can tell you it was well in excess of 250 grams per day: These are the typical foods I ate day after day:

Chicken: Breasts, legs, whatever
Cheese: various kinds, the lowest carb types
fish: mostly fatty fish, mackeral, herring, salmon
Protein Powder: various types, whey, egg, etc.
Veggies: huge portions of spinach, turnip greens, brocoli, cucumber
Nuts: walnuts, pecans, hickory, brazils, (no cashews)
Once per week: bacon, pork, beef, eggs

Based on that list, I'll guess that you didn't find the appropriate fat/carb ratio for your particular body. It is easy when coming from a low fat perspective to dramatically underestimate the number of fat grams your body needs for fuel in place of the carbs.

And it sounds like you probably never brought yourself up to a maintenance level of carbs. With no weightloss needed and a very high activity level, you do need considerably more carbs than us sedentary types. Somewhere between 75 and 125 at a guess.

Provide enough carbs and proteins to fuel your muscle and enough fat to fuel everything else.

Rocky -

how much fat were you ingesting? I'm just curious because my first time round doing Atkins I didn't consume lots of fat and I did consume lots of protein and I got tired on such low carbs (~30g veggies only).

I could be wrong as it is still early days, but on the days when my fat intake is very high I find I have more energy, especially for intense exercise. I think my overall calories are much the same because they ALWAYS are - even when I'm doing higher carbs. My appetite really does regulate my calorie intake, wherever those calories come from.

This morning I had bacon and eggs; the eggs were fried in the bacon fat (and there was a lot of fat!). Well I had a lot more energy today - this had happened several times.

Why don't you play around with ratios a bit more? I ended up coming back to low-carbing because of other health problems (allergies, moodiness, anxiety) and had similar issues regarding wellbeing during intense training - but I'm finding that my body IS adapting - provided I eat enough fat.

Loops

This looks more like OWL than maintainence. You could add some higher carb veggies in there like carrots, winter squash, brussels sprouts, tomatoes, sweet potatoes, etc...along with some whole grains (whole rolled oats with some protein for breakfast, for example, or a little wild rice with dinner), a serving or two of lower GI fruits (think berries, melons, peaches, tangerines, etc...). 250 grams of protein seems a little high for someone of your weight, but that's just MO; controlled carb is supposed to be adequate protein, not necessarily high protein; maybe drop the protein a bit so you can compensate for the extra carbs and calories from the extra veggies, grains and fruits.

Lisa N, I know exactly what you are saying....but when I think about it I MUST have been getting at least 100G carbs/day with all the nuts I was eating. I loved nuts and they do supply carbs (very low GI mind you) when you eat lots of them, especially peanuts. I did not want to use starchy veggies or grains because they aren't exactly on the LC friendly foods list.

If you're looking to improve athletic performance on low-carb, then you should be trying for around 70 grams of starchy carbs per day. Vegetable carbs alone won't fill the bill; you need at least some starchy carbs. Add some good amounts of butter and other animal (not lean) meats, and you'll see improvement. Don't depend solely on vegetables or nuts for energy.

I'm not sure which list you're referring to unless it's the allowed list for induction. Atkins for life lists all the higher carb veggies I mentioned previously as acceptable when eaten in moderation for those following maintainence.
Depending on your individual carb level, you could also be including things like lentils, hummus, chick peas, kidney beans, barley and peas. Not all at once or on the same day, of course, but there is certainly a great variety possible and no need to stick with primarily salad greens as your vegetable choices.

Low carb is not about avoiding carb food. There is nothing wrong with apples and oranges, and oatmeal, they are healthy foods. The only problem is if the amount of sugar these foods contain is too great for your tolerance (determined by lifestyle and metabolic rate and sugar sensitivity). You were eating an induction diet. The majority of people find it very difficult to do that much activity on that few carbs. In fact my lifestyle is average, I weigh only a bit over 110, and am female, and even I eat oatmeal and apples from time to time (in fact I had a half portion of oatmeal and apples yesterday, with nuts and butter and fat milk of course... this was not a problem because I tapered the serving size to account for my intolerance for large amounts of carbs).

If you were eating 100 grams of carbs worth of nuts, then you must have a VERY high metabolic rate, in which 100 grams of carbs is still a very low percentage. The absolute gram number is not as important as percentage of energy (when we are talking about maintenance diets, anyway).