I have been using sites such as MyFitnessPal and Fitbit to track my calorie plan, my intake v. plan, and my exercise. My BMR currently is 2094 calories per day. That is what medical science says I would burn if I laid in bed and did nothing. I start with that and make two adjustments: adjust for my activity level and adjust to lose 1.5# per week. This means that, according to the studies, if I eat <1763 calories per day, I should drop 1.5# per week. So I am eating to average ~1700 calories and over a given week, I am within plan.
So the eat plan is based on my BMR and my normal activity. I am then adding workouts on top of it. This week, I will work out 6 times, with a calorie cost of between 350 and 1400 per workout. This is 4177 calories this week or an average of 696 per day. This should be another 1.2# of weight loss.
I am not losing 2.7# per week. One symptom I have had is being cold at my desk and in bed at night. Anecdotally, I attribute this to my body producing less heat when I am not running to make up for the extra energy used during workouts.
It is a myth that exercise increases your metabolism, muscle burns more, our western society has slowed our metabolism, etc. The studies just don’t show that. Pontzeri, Raichlen, Woods, Mabulla, Racett, and Marlowe have an interesting study that attempts to measure the metabolism of members of the African Hadza tribe with westerners. The Hadza still live a paleolitic hunter-gathrer lifestyle. Their conclusions are striking:
Measurements of TEE [total energy expenditure] among Hadza hunter-gatherers challenge the view that Western lifestyles result in abnormally low energy expenditure, and that decreased energy expenditure is a primary cause of obesity in developed countries. Despite high PAL [Physical Activity Levels] and dependence on wild foods, Hadza TEE was similar to Westerners and others in market economies
The similarity in TEE among Hadza hunter-gatherers and Westerners suggests that even dramatic differences in lifestyle may have a negligible effect on TEE, and is consistent with the view [4]–[7], [16] that differences in obesity prevalence between populations result primarily from differences in energy intake rather than expenditure.
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0040503
So where does that leave us. In my case mostly confused. I know that “expert websites” including the two that I use, plan calorie intake based on BMR+Lifestyle+Extra Calories burned by workout - Desired Loss = suggestion. Note above that I don’t use that; I am not adding calories to my intake for calories I burn during workout. Because that does not really change my BMR; it seems like the body just burns less calories during non exercise to make up. Despite my higher PAL (running/swimming/etc), my TEE is not changed. It is simply a function of my weight. Hence I am not losing an extra 1.2# per week with my 4177 calories burned during exercise.
I really think much I have heard recently on weight loss and the calculators on these websites is flat wrong. People are working hard to get those “bonus calories” from exercise and then frustrated when there is no weight loss.
I was recently reminded that the wise farmer/rancher always plans based on the concept that the drought might start tomorrow. Or body seems to do the same. Mine seems to be holding back because of my reduced calorie intake; I am not losing a full 1.5# every week that the math says I should. So I am cold at times, and there are other unnoticeable things my body is doing to try to save calories in case there is a drought tomorrow. But it certainly is not straight math and frustration must be dealt with.
The one thing I don’t know is what happens when calories burned in exercise constantly exceeds intake. There must come a point where the body cannot slow down enough during non-exercise periods to keep TEE constant. But there are two problems with this. Although TEE/BMR goes down with weight (so less calorie burn is needed to exceed it), the calories burned by any activity also goes down. It takes a 250# person more energy to move one step than a 150# person. The BMR calculator says if I laid in bed every day with no movement, I would burn 14,658 calories per week. At 4177 calores from exercise, I would have to increase my training 3.5x to reach the point where my exercise is burning as many calories as I would burn otherwise. Somewhere on the way to this point, my body would start burning my fat stores much faster and I would see rapid weight loss from exercise. But I don’t have the time and I am not sure my body could take 4 hours per day at the level I currently exercise. Endurance athletes do eat more without weight gain and do lose weight during long exertion (beyond just fluid loss). But I don’t think that exercise, for most of us, can affect weight loss directly.
If you are exercising to lose weight, you will fail, become discouraged, and lose the ability to motivate yourself to exercise. Pure and simple; the studies are clear*. Unless you are going to extreme levels of exercise, it will not change how many calories you burn in a day, week, or month. It will make you more hungry, and if you believe the formulas with their “bonus calories” for exercise, you will overeat and gain weight.
(* I realize they are not fully clear, there is a lot we don’t know about metabolism, etc. Hence the details that frustrate me because my math does not add up exactly every week with a precise 1.5# weight loss. But I think on the macro level, the studies support my point pretty clear).
Ok, now that I am this far out on a limb, let me go farther. Type of food has no effect on weight loss. The Hadza are on the “whole foods” diet and their TEE is not any better than ours. Many Paleolithic people have periods of the year where their primary food intake is honey, which is really not that different from our high fructose corn syrup. There is not a food group that slows down or speeds up the bodies metabolism. Where food does differ is that western diets are full of easily accessible energy-dense but nutrient poor foods. This makes it easier to intake calories above what your body can use. We get fat!
It is not the type of food, it is not the exercise, it is the amount you eat that causes weight gain or loss. But I would say exercise and food choice can help you reach your weight loss goal. You have to eat a ton of raw spinach to ingest the same calories as a big Mac. Your body will be full with less calories and perform better with the spinach.
I have switched my focus to losing weight so I can run better. My goals, races, and accomplishments are motivating me. My eating has become a part of what I need to succeed, just like massage, ice, etc. I love eating and love food. But a cheeseburger and beer today is going to feel like crap during my race in the morning. I need different foods in my diet to perform. I need the right nutrients. The exercise is causing my body to want those nutrients and it really doesn’t like the wrong nutrient-poor foods. And then I perform poorly in a workout or a race and my motivation causes me to go back and say what did I eat; can’t eat that anymore.
When I focus on the results of exercise, eating the “wonder foods” because they do effectively give you necessary nutrients becomes easier to make a habit. And that is what we are really looking for. Each of us needs to understand what is fact and what is fiction, and build our goals and plans with that knowledge based on what we want to accomplish.
It is a process and not easy. I drive by a place like Five Guys Burgers every day and want to turn in. But I am on an aweful long streak; the longest of my life, of continuing to drive by those places, order the salad at McDonalds with Grilled Chicken, etc. It is a temptation and a choice at every meal, but if you have a motivating goal, and really understand how to get there, it is possible.
Two closing notes:
1) There is a silver lining to the obesity epidemic in America: there is a lot of money and interest in studying the problem and we are learning more and more what really works. This is a topic that every person needs to stay on top of because surprises like the Hadza study come along and challenge the conventional wisdom and we need to use the new facts to evolve our thinking and actions.
2) YMMV -- For every rule, there is an exception. There are diseases, conditions, genetic factors, etc. that will alter how some people react under my program. It seems to be working for me, but there are a lot of medical factors means it will not work for everyone. Simply put, you need to research and control the process to find out what works for you.
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