Trying to dispel some dieting myths here and the erroneous beliefs in Starvation Modes, calorie counting, muscle loss and Thermogenic effect of eating.
So we've gained weight and carry this weight around in the form of engorged fat cells. Fat cells have blood vessels flowing through them and there is a metabolic cost (takes more energy) of maintaining them in this engorged state. Now add on to the fact that we've gotten older - everything tells us as we age, our muscles reduce so our Basil Metabolic Rate (BMR) decreases. So we're burning a little more from excess fat and a lot less from Muscle Atrophy (age = more sedentary, less muscle use=Atrophy). It's diet time!
BMR is the rate at which our bodies burn energy just live if we do nothing but lay in bed all day. Let's say that's 1400 calories. Very few of us are that sedentary that we lay in bed all day, so we get up and use the bathroom, make some food, walk to and from the car to get to work, etc. Let’s say that burns us another 500 calories on the day, so our total caloric burn is 1900. This means if you eat this much you'll neither gain nor lose weight, but we want to lose weight and all the information says 1-2 lbs. a week is good. A pound of fat is equivalent to about 3500 calories, so to lose a pound you have to burn this much more than you take in - a bit daunting as a number, but if you break this down to 500 calories a day over 7 days, that is 3500 or a lb. of fat a week that has to be used to maintain you daily life. All well and good and we do this for several weeks and loose say 10 lbs. Awesome - good job!
But now there is 10 lbs. of fat which no longer has to be maintained by our bodies so our BMR goes down a bit – let’s just say 100 calories, so now our BMR is 1300. If we do nothing to add to our activity during the day, we are moving 10 less pounds around, so our burn rate decreases too - say another 100 calories. so now we are at 1300 plus 400 or 1700 calories a day, but we continue to eat 1400 per day so our deficit is now only 300 - times 7 days or 2100 calorie deficit a week or 0.6 lbs. Extrapolate that out and as the weight goes down, so the caloric burn until we are no longer losing weight because we no longer have a calorie deficit.
What to do, what to do? We have to get our deficit back which we can do by either eating less or burning more. The problem with eating less is we start to sacrifice the nutrients our bodies need which could, in turn, hider fat loss. The answer is burning more. So we have to become more active. We have to either increase the amount of exercise or the intensity of exercise. There is a balance to be achieved here as well. Some exercise is good, but a lot can cause the increase in cortisol - a stress hormone - and hinder fat loss. If we aren't doing any exercise then adding some is great. This is where devices like fitbit are great. They can motivate you to get out and just walk more without a lot of stress. An hour of walk can burn about 200 calories (varies depending on your weight and effort). Gee, that's exactly the amount we lost from our loss, so an hour a day gets us back to our 3500 calories a week and we overcome our slowdown and continue to loose.
This will happen again and again during the weight loss journey. As you lose, you must increase your rate of burn. The only way to keep this balance is to know what you burn and what you eat. You have to count calories in and out and you have to do it consistently. There has been multiple studies done where people claim they eat so much, but when it's tracked, they eat much more. The reverse has also been found in people who claim they can't gain weight as they would like. Estimating calories if next to impossible.
But didn't I say too much exercise would release cortisol and hinder weight loss? Yes, but as in all things there are multiple variables to consider. It seems the cortisol is related to time and not so much to intensity. Plus it is a response to too much stress being put on the body. But the body adapts as well, so what may be too today may not be too much tomorrow. What I mean by that is as we get in better shape, it takes more to get the level of stress. Intensity of exercise is a way to get there.
Intensity is the level of effort that is put into an exercise. For example, if you walk 2 miles every day, you'll get to a point where that goes from difficult to easy. As you get in shape, the effort required is relatively less, but if you pick up the pace and jog, the intensity goes back up again and you burn more calories. As that becomes easier, you run. Then you run faster. Then you run up-hills. It’s the same with resistance training. You lift 10 lbs, then 15, then 20 and you keep building up. You can lift faster or you can lift super slow. So by upping the intensity, we can consume more calories within a given time frame and not have to work out longer adding to stress. There is some potential to add time as well as the body adapts, but that seems to come more slowly than intensity build up.
So now let's look at the frequency of eating. A strong adage is to eat 6 small meals a day to boost the metabolism. Any benefit from eating comes in what is known as the Thermogenic effect of digestion. This has been measured at about 10% of the calories consumed are used to digest those calories. If you eat 500 calories, 50 go to digestion. If you eat 1500, 150 go to digestion or increase in metabolism. So if I eat 250 calorie meals, six times a day, I'll consume 1500 calories and boost my metabolism by 150 calories. If I eat one meal a day that is 1500 calories, I'll boost my metabolism by 150 calories. Small meals, big meals - other things being equal have no bearing on metabolism. The problem with six small meals is that each time you eat, your body secrets digestive hormones including insulin. What you are in effect doing is keeping your cells constantly exposed to insulin. It is believed now that this constant exposure is much like any other drug, the cells start to become less sensitive to it and it takes more and more to get the same effect. This is known as insulin resistance and is associated with pre-diabetes. Eating only once or twice a day and fasting the rest of the time means there is time when your cells are no longer exposed to this hormone so when it is, it's more effective in smaller doses.
Glycogen vs ketones. Glycogen is the primary source of fuel for our muscles and brain (made from blood glucose to be stored in the tissue for conversion to energy through the ADP to ATP cycle) when we have it in our blood stream, but recent tests on animals indicate the brain may actually work better on ketones. Ketones seem to stimulate production of growth hormones which, in turn, cause stem cells to grow into more brain neurons. Ketones are the energy source that results from the breakdown of fat and this can be used by both the brain and muscle tissue for energy in the absence of blood glucose. In addition to glycogen for energy, muscles also need Branch Chain Amino Acids to help with repair and growth. A diet high in good quality proteins can proved all the BCAA's necessary to prevent muscle loss while the ketones provide the energy. This is how we can loose fat without loosing muscle and keep our metabolism at its highest possible level. If we are doing weight lifting and eating enough protein, you can actually gain muscle while loosing fat. The myth that fat lose automatically equals muscle loss is a very persistent belief. It's my opinion that any muscle loss associated with dieting is when the dieter either stops, reduces or never has exercised for strength and the muscle atrophy from non use rather than reduce from the so called "Starvation mode" or catabolic state. Also remember that glycogen (glucose stored in the tissues for energy) is produced from a process called glycogenesis which is driven by insulin. As long as you have blood glucose, insulin is converting it to either glycogen or fat. If you don't have glucose in your blood, the insulin stops and you start breaking down fat to replace the energy being used by the consumption of glycogen. The more you work your muscles, the faster you burn up the glycogen and need more ketones to replace them.
So it’s not just about the burn during exercise either. Strength train is a very intragal part of dieting. I've already stated that if we have enough BCAA in our diet, we can actually gain muscle while losing fat. In addition to that, fasting can increase the amount of growth hormone which helps us build muscle. Remember when athletes used to take testosterone to get a competitive advantage, then they started testing for it, so they switched to HGH (Human Growth Hormones). They test for that now too, but you can get a similar effect (though not to the level of supplementation) through fasting. I personally do my strength training at the end of my fasting period. In six weeks I've had a 13% increase in strength as measured by my increase in lifting volume vs before fasting. I am eating about 1500-1800 calories a day with lots of protein to include whey protein supplements and loosing on average of 2.67 lbs. a week while getting stronger in the process. Also, strength training increases metabolism for as much as 48 hours after the exercise to repair and build the muscle. Cardio (aerobic) burns during the workout and Strength (anaerobic) burns after the exercise. Of course if you run hard enough and long enough to enter anaerobic state, it would work the same.
So there are a few additional things I've done too. I make my own juice weekly which is a formula I designed based on additional research. It seems some things like beets increase nitric oxide in the blood that help with blood pressure as well as stimulating some testosterone production. Pomegranates and Onions also increase testosterone. Cruciferous vegetables provide an element that binds with OEstrogen in men (stored with fat and released when fat is burned) to help metabolize it without it becoming estrogen, so lots of them. Fruits like berry's and grapes also have benefits. I drink 8-10 oz of this everyday with some added whey protein powder and kefir for digestion and a liquid vitamin.
I hope this sheds some light, especially for those who are having difficulty losing the fat. I have done a lot of self-experimentation on these principles and found them to be true for me. I get them from scouring the internet and looking mainly for scholary papers and not just blogs and internet hype. I discuss the principles with various medical professionals as well (even they don't always agree. I'm also informed that nutrition and weightloss is one of the most controversial areas of medicine). Then I apply some common sense thinking to evaluate the logic of each principle in a gestalt perspective. You can dispute these principles all you want, but you can't dispute the 42 lbs. I've lost practicing them.
Good luck to you in your journey.
“Your assumptions are your windows on the world. Scrub them off every once in a while, or the light won't come in.”
― Isaac Asimov
“Being ignorant is not so much a shame, as being unwilling to learn.”
― Benjamin Franklin
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