Maintenance calories are the approximate amount of calories you must consume per day on average that with your typical diet (food you eat), exercise, and activity, ensures that you neither gain nor lose weight. I’m taking this definition a bit further to specify that no only is it the level at which you don’t gain or lose weight, it is also the level at which your lean body mass and fat mass does not change. For purposes of my calculations, I assume that body mass is split into one of three categories:
- Lean (everything else)
One issue that I’ve had in the past with diets is that I don’t actually know the value of maintenance calories. Well, over the next couple weeks, all this will change. Starting this past Sunday (January 15), I’ve been keeping what I hope is an accurate account of all the calories I consume. Using my body weight, body fat percentage, and body water percentage prior to eating that Sunday and prior to eating on the upcoming Sunday, I can calculate the change in fat, water, and lean weight.
Starting with total calories consumed over the past week, I then add or subtract amounts based on how the fat and lean mass changed (here, I assume that all change in lean mass is solely from muscle growth or muscle attrition). For example, let’s say that my calories eaten for the week is 7000 calories. From the calculations, my lean body weight did not change, but I lost 1lb in fat. I would then add 3500 calories to 7000 to account for the fat lost, then divide by 7 to get an approximate maintenance amount. This is the amount of calories had I eaten per day, would have resulted in no change in fat mass or lean mass.
Similarly, if I’d gained 1lb of fat, but lean mass remained the same (I know mass and weight are not the same, but for the purposes of this discussion, since I’m never leaving earth and therefore under the influence of the same approximate force of gravity, talking about changes in weight relatively speaking is equivalent to talking about changes in mass and it so happens that mass is the vernacular here), then I’d subtract 3500 from the 7000 to account for the fat gain, then divide by 7. So, while 3500 calories per pound of fat is the generally accepted number, I’m going to need to do some research to come up with what I hope is a reasonable estimate of the amount of calories consumed in generating a pound of muscle.
Now, I know some will be quick to point out that in terms of macro nutrients, fat is composed of different things than muscle so the 3500 calories that go into fat will be different from the 3500 calories that go into muscle. Here is the thing, as it turns out, your body will convert anything to fat. So if there is unused energy in the body, regardless of what it was made up of, it will be turned into fat. So whatever isn’t used to keep me alive and build muscle, must necessarily be turned into fat. Now, that’s probably not 100% accurate, but that’s pretty much the big picture everyone follows when it comes to doing these fat gain/loss weight gain/loss calculations. Anyway, as it turns out, regardless of what our bodies actually does with the excess calories, assuming that change in water levels incurs no caloric change and that the conversion factors for calories to pounds of muscle and fat are accurate (or very close), then the calculated maintenance level will be just as accurate (or close).
A quick caveat. Research has shown that your metabolism changes depending on how you eat (or don’t eat) and how much muscle mass you have. So the value I get will be most applicable to when my muscle mass is about the same as it is during the period of data collection and when I’m eating, exercising, sleeping, and at the same activity level as the time of the period of data collection. In other words, if any of the following is different, I can expect that my maintenance calories will need to change to reflect the impact on my metabolism:
- Statistically significant change in muscle mass
- Change in eating habit (currently fast 16 hours, eat during an 8 hour window) – even if daily and weekly calories stay the same
- Statistically significant change in sleep length and/or quality (for example, let’s say I still sleep 8 hours, but only half as much in REM – this is a statistically significant change in sleep that will affect metabolism)
- Exercise and/or activity level
So all that said, I’m still looking forward to finally quantifying this. Based on my past experience, I expect it to be low (between 800 and 1000 calories per day). The only times in my adult life (only time in my life that I actually kept track of my weight enough to really notice changes like this) that I remember significant weight loss (so loss that couldn’t be simply explained by loss of water – I weigh about 200lbs. So a 1% change in water level is a change of 2lbs. On a hot summer day, I could lose 6 – 8lbs or more simply from water alone and not feel too different health-wise, especially if my activity level dropped near the end of the water loss. Of course, in the process of rehydrating later that day or the next, I’d gain most of that back) are the times where for whatever reason, my calorie consumption was very low (1000 calories would be a big day).
Based on my experience over the past month, I could probably sustain 1000 calories a day over the long term with about 2 days a week that either have un-suppressable craving or just out and consuming more because I want to. By cravings, I’ve not yet found myself to have cravings for anything specific, foodwise or even macro nutrient wise. So my cravings don’t lean towards carbs or protein or fat, just for more food in general.
Anyway, the point of saying this is that at the moment, I just follow a strength training program 3 times a week. Now, I’m actually going to be working out every other day, so every two weeks, I gain a day which I’ll be using to play catchup with either extra work on my form on an exercise or to evaluate my performance on something that isn’t part of my normal weekly routine. But after I reach my current body composition goals, I can add cardio to my off days to help offset those overconsumption days each week.
Though I am considering adding cardio sooner to help accelerate my fat loss (at the expense of muscle gain – I feel that I have an almost acceptable amount of muscle, so actually knowing my maintenance calories would help me dial in cardio especially if I could maintain muscle mass and thus, minimize variation in metabolism as my weight drops). But that decision will come at the end of January after I evaluate how three weeks of the default leangains has specifically affected me.