Activity Calories: Log them or not?

Azdak

For some light Sunday reading, I am reposting a blog I wrote 2 years ago concerning activity calories:


A constant question on the forum is "Should I count "X" activity as exercise?". The "X" can include everything from standing, to housecleaning, to yard work, to golf, to sex--and everything in between. Usually it is some one new to MFP who has just started a program and who is trying to be diligent about monitoring energy intake and output.


This is one of those questions that comes up all the time, so I am just going to address the whole topic and post it as a blog for future reference.


First and foremost, it is essential to remember that when we track calories, it is an external accounting system that exists primarily in our minds. It is something we use to try to describe reality, not the reality itself.


By that I mean that your body already keeps track of calories in and calories out. It does so very precisely, 24 hours a day, 7 days a week, 365 days a year. It is 100% accurate. If you want to look at the "balance" in your "calorie account", all you have to do is take off your clothes and look in the mirror.


Although the body is extremely accurate, it doesn't give much insight as to what is going on day to day. As you plan your diet and exercise program, obviously it is important to track calories in and calories out. It is just important to understand that these are all indirect estimates of what is happening in your body.


As many of us are aware, losing fat requires a sustained calorie deficit--you must expend more energy than you take in. Total energy expenditure consists of Resting Metabolic Rate (RMR) + Thermic Energy of Food (TEF) + Thermic Energy of Activity (TEA). TEA can be broken down in to exercise energy expenditure and casual activity.


We can calculate BMR or Basal Metabolic Rate with a reasonable degree of accuracy. When using a site like MFP to determine your recommended daily calorie intake, the TEF is automatically included. That leaves activity calories. Exercise workouts are discrete events that normally consume a lot of calories, and we have a number of tools--HRMs, formulas--to calculate the energy expended, so we usually count that separately. Exercise is also not something that everyone does every day.


That leaves calories expended during casual activity (including work). That can be a significant amount--even for a sedentary person, it can be 15%-25% of total energy intake. And it's the most variable and least quantifiable part of the equation. Since casual activity varies so much, the standard tools that calculate total daily energy needs use a standard "factor" to calculate the amount. The "activity factor" is an average calorie output, based on one's job requirements and daily activity habits.


The key word here is AVERAGE. Some days, people will move a little more, some days a little less. Sometimes people will do a lot of additional activity at one point in the day, but do less the rest of the day. Over time, the busier days will be offset by the more sedentary ones.


So let's go back to the original question and discuss the pros and cons of each approach.


The biggest argument I have heard from people who like to track housework and other ADLs is that keeping a "score" motivates them to be more active. Kind of like wearing a pedometer and having a goal of increasing the number of steps walked each day. Certainly I can understand that reasoning. If you are using activity calories as that kind of "scorecard", and you have a system that works for you, then it can be a positive thing. However, I would not recommend using those numbers in your eating plan--at least, not on a regular basis.


Another reason I hear is that people are afraid of "starvation mode"--they include extra activity calories because they don't want to undereat. This one I think has to be approached with some caution. The response to a large caloric deficit varies widely -- by individual, by overall plan, by body fat levels, be length of time on a weight loss program, etc. I am not saying there are not negative effects from sustaining too high a caloric deficit, but I think the "fears" are greatly overstated, especially for people starting a weight loss program. In most cases, calculating a BMR, adding in an activity factor, working out, and properly refueling after a workout with provide more than sufficient calories to avoid any type of "starvation mode" even with a large caloric deficit. Part of the problem is that people persist in arbitrarily choosing 1200 calorie/day eating plans, when it's not appropriate.


A third reason would be logging activity calories so that you have a greater allowance to eat more. I don't think I need to elaborate on the potential pitfalls of this approach.


What are the reasons to recommend against logging calories?


First goes back to my earlier statement that the "activity factor" built into your recommended daily calorie intake is an AVERAGE--it's not the automatic minimum that you use each day. Things like walking the dog, doing light housework, regular yard work, shopping--these are already included and accounted for. Human beings are experts at having selective memories. It's easy to remember the hour you spent moving furniture and forget about the weekend you spent with you butt glued to the couch. Unless you are wearing a device such as a Body Bugg, or keep a minute-by-minute movement log, it is difficult to measure variances in casual or work activity with any degree of accuracy.


Second: this is related to the other argument. I have read numerous studies that show that, on average, people who start diets decrease their casual activity; studies that document that people who start vigorous exercise programs decrease their actvity the rest of the day following a workout; studies that show that people who start new jobs that involve an increase in activity, tend to significantly decrease their exercise activity. Unless you make a conscious effort to maintain or increase casual activity, it is easy--actually, it is likely--that you are overestimating your activity caloric expenditure.


And lastly, if you think the tables and sources for estimating calories expended during exercise activity are inaccurate, they have laser-like precision compared to the references used to estimate activity calories. Often, these tables were measured using small sample sizes, so they have wide variability; plus the numbers often are only valid for continuous activity, not the intermittent way we normally perform these types of activities.


Basically, the more detailed you try to be in logging activity calories, the higher the likelihood that you will overestimate your total caloric expenditure.


Someone who already has a system and has figured out their own "calibration" or technique, and is realizing success should obviously continue what they are doing.


But if you are just starting a program, and wondering if you should log miscellaneous casual activity, I would strongly urge caution. Think about what you are doing and why you are doing it--don't just assume this something that everybody does. If you are 40, 50, 60 pounds overweight or more and you are eating in the 1400-1500 calorie/day range, you have little to fear from "starvation mode", so you can afford to be cautious about overestimating activity calories.

robert65ferguson

Thanks Azdak for yet another really informative posting. You always provide a lot of really helful advice which I for one really appreciate and try to benefit from.

Sycoholic

I set my daily goal. I wear a hr monitor occasionally to make sure I'm accurate. Really, I'm not worried about a few hundred calories either way, but this helps satisfy my curiosity. I have encouraged others to do so and you can even find them relatively cheap at WalMart even. Mine is a $69 GPS HR monitor watch from Amazon. Look up "GPS Navigator watch". I find it extremely helpful and I use it to make sure my heart rate stays elevated at the gym as it's sometimes hard to tell the difference between 90bpm and 120bpm when you're busy lifting.

Azdak

I set my daily goal. I wear a hr monitor occasionally to make sure I'm accurate. Really, I'm not worried about a few hundred calories either way, but this helps satisfy my curiosity. I have encouraged others to do so and you can even find them relatively cheap at WalMart even. Mine is a $69 GPS HR monitor watch from Amazon. Look up "GPS Navigator watch". I find it extremely helpful and I use it to make sure my heart rate stays elevated at the gym as it's sometimes hard to tell the difference between 90bpm and 120bpm when you're busy lifting.

I don't know if you are going to like this, but you might find it worthwhile reading:

http://www.myfitnesspal.com/blog/Azdak/view/the-real-facts-about-hrms-and-calories-what-you-need-to-know-before-purchasing-an-hrm-or-using-one-21472

Sycoholic

Oh, I totally understand your blog. I'm fine with it. I have all my information entered in and it's accurate. It doesn't have a way to input VO2 but it is a cheapy. I basically want an idea of my heart rate and the gps function was what I was initially going for. The gps is accurate and I've manually checked my hr against the watch (which has a chest strap) and that's accurate. The calories are usually a hundred or so either way with MFP's estimates. I don't use MFP or my watch as "Gospel" when it comes to the numbers. When I'm referring to keeping my heart rate up while lifting, if it's dropping down to 80, 90 then I know I'm stalling between sets. After a set, because of the pressure, it's about 140, quickly dropping to about 120 after I sit up. It's just a guideline that keeps me hammering away at the weights, not a set in stone accurate accounting for anything. I don't believe in using a hr monitor to do anything other than hr accurately. (except gps in this case) But really, for people who want to post ridiculous amounts of calories burned for an hour of yard work, it might be a good idea to use one and see how it correlates. It does seem a bit crazy that I can run for an hour and not burn what they do in an hour of housecleaning, gardening, etc.

cathyhennes

Thank you for posting this. Do you have a Web site address for your information? As a former WW person, I think they are giving them the wrong information about Exercise (Activity) Points. Yes, it helped me lose 120 lbs, but there's more to food and exercise than just points.

I've gone further than WW and quit. I am actively using MFP and have to track macular level (sodium and sugar are the biggies for me). Every time someone posts on FB about what they find that's good to eat for WW, I am posting information about why it's NOT good (the foods are VERY high in sodium levels).

Again, thank you!

Cathryn Hennes, M.Ed.

cathyhennes

If I share your information, I want to make sure I give credit where credit is due and link to your site.