Body Energy Usage

I ponder macro-nutrition needs a whole bunch. Here’s what I have handy, though my technical references are scattered and omitted.

There’s always a need for roughage, vitamins, and minerals, which come from foods with very low calories/kilojoules. Aside from that, the three main macros have specific needs.

A body needs 125 grams of carbs for your brain/nerves; just under 1 gram of protein per kilo of lean body mass to maintain tissues/muscles; and around 30g of fat for cellular and neurological structures. This is usually around 1200 kcal per day, but varies by person 10-20 percent.

Anything else you eat is either poop, or gets converted to sugar. Sugar is burned if it’s needed immediately for exercise (growing, standing, walking, cardio, whatever, anything other than sleeping). Any sugar that is not immediately needed is stored in muscles as glycogen, up to around 4% of your muscle mass. All sugar past that is turned into fat and stored in our fat cells.

This is where “whole grains” comes into play. If it’s not ground up, it takes longer to break it down. However, if you take grains, and mill them into a powder, IT IS NOT WHOLE GRAINS. Just because there is fiber in the food does not mean it’s slow to absorb. The less processed the food, the longer time period over which it trickles energy into your body. If it’s super processed, it all absorbs very quickly, and your body may have trouble figuring out what to do with it unless you’re depleted already.

This is also where some insulin resistance comes from, and why diabetics have normal sugar metabolism in their muscles during exercise, even if they are short on insulin, or are resistant to it. Resistance is GLUT4 which causes glucose receptors to move to the cell membrane, but exercise does the same thing – muscle is hungry, it asks for more. Muscle is not hungry, it asks for less, even if you try to overfeed it. Where would it put this excess sugar? It can only store so much.

During exercise, your fat cells can liberate about 90% of your weight in pounds as usable calories per hour. For me, it’s about 260 calories. The gap is made up from glycogen in the muscles, which is good for just about 90 minutes. If you exercise hard, and stop at 60, and rest for 30, those 30 mins still use up that glycogen for delayed processes, cleanup, etc.

Eating carbs cannot provide as much energy as glycogen, but it’s the next best thing. Also, if you’re fasting, your glycogen reserves get burned up pretty quickly. Glycogen is 3:1 water to sugar, so this is why the first week of dieting is so awesome. No, that’s not fat. It’s muscle energy.

Any energy deficiency not covered by food will be covered by muscle damage. About the same number of calories can be broken down out of injured muscle cells. For me, this is a total of muscle and fat sourced calories of about 520 calories per hour. If I exercise for 3 hours with no food, then my power output drops to 130 watts, which is about 520 calories per hour.

The best option to limit muscle damage, limit recovery time, and optimize exercise benefits when going for more than your glycoge, is to eat as much every hour as you burn, minus the calories that can come from fat. Staying carb focussed can give more energy, and can be easier to absorb, though for some people, this slows the breakdown of body fat.

Staying fat focussed keeps the fat burn mechanisms running, but it takes twice as much oxygen, which means you’re hear-rate limited. It’s less about muscle conditioning then, and more about cardiovascular improvement.

Staying protein focussed is tougher on the kidneys. The aminos have to be converted for use as fuel, and that’s a lot of extra ammonia to pee out. That can be an issue when dehydration might already be at play.

General health

I just saw a picture of myself from today’s bike ride, and while I’m still wanting to drop pounds AND fat, I’m about as happy with how I look as I can ever recall being.

In the mirror this morning, I noticed SAGGY BELLY SKIN. This is a good sign, and I’m young enough that skin-shrink is just barely lagging behind fat loss.

Health-wise, my right knee, low back, stamina, and self image all are massively improved. Circulation is better. My BP and cholesterol were good before, so no real change. My resting pulse is down a little bit. I’m having fun exploring and spending time with people. I’m enjoying measuring my progress technically, and seeing myself exceed goals. Also, endorphins.

Also, the rates at which I can convert fat to muscle show me that I don’t have any metabolic issues. “Weight loss is all in my head.” So, picking the right foods will be key. I’ve found I really like Greek style yogurt, and it’s low fat, high calcium, high protein, and only has moderate carbs if I have the mix-up jelly kind (I do).

It seems calorie dense, but it also seems satiating. One day I had 500 calories of it to finish off evening hungers. Then next day I had 2 in the evening. The next morning, I had 2 for breakfast, and had no real hunger for most of the day. I had another before riding my bike, and a snack bar, and some carby elecrolyte drink. I blew through 4000 kcal today and have eaten under 1100 without hunger.

I did have a bunch of caffeine today, so I need to test further. If I could eat 120-240 kcal and be satiated for 6 hours, that’s just famazing and would be a big win for me.

As to wanting to drop pounds and fat:

  • I’m 29.6% body fat based on bioelectric impedence, and the increased risk limit is 28%. I’d like to get down to 25%.
  • My Waist to Height ratio is 56.7%, and the increased risk limit is 53.6%. I’d like to get down to 50%.
  • My Waist to Hip ratio, which is an accurate predictor of morbidity risks, is 95.76%, and the risk limit is 90% for men. I don’t have a target for this other than the risk limit or below.
  • I’d like to drop to a size 36 pants due to availability of tall clothes. Also, I found out / confirmed that even men’s clothing is vanity sized by 7-10%, so tape measures differ vs pant sizes.

I just had a life insurance medical exam. It’ll be interesting to see what the CBC comes back with.

Photos, with me on the far right:
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