To best calculate your daily caloric needs, you can use the Compendium of Physical Activities Tracking Guide [link]. It’s a huge list of very specific daily activities, including physical activities at different intensity levels as well as general tasks, such as eating in church. For each activity, calorie output is represented by a number called “METS” (metabolic equivalents).
To get calories from METS, multiply your weight in kilograms (pounds divided by 2.2), and multiply by the number of hours you performed the task for.
For example, if you weigh 70 kilograms and went to dig worms with a shovel for 30 minutes, you look that up on the chart. It’s METS = 4.0. Calories burnt = 70 x 4.0 x 1/2 = 140 calories.
To find out your daily calorie needs, take an average day, and track all of your activities during that 24 hour period, including sleeping, walking, studying, exercising, eating, etc. The more detail you put in, the more accurate your results will be. Here’s an example for one of my days:
Daily Calories Example
As you can see from my example, I’m burning about 3600 calories in that day. But if you saw my previous post, my average output is 3200 calories a day. This is because for this sample day, I’ve included my morning bike ride – but I do not do this everyday. To compensate, you may need to average a few days worth of calories.
Of course, these figures will be different based on your age, gender, metabolism, etc. But overall, they are pretty accurate, especially if you are exercising a lot. This is because metabolic differences will become small relative to calories consumed during exercise.
Now all you need to do is consume a number of calories that’s approximately equal to your caloric needs if you want to maintain your weight. And if you’re trying to lose or gain weight, then eat less or more! A good estimate for calories to burn is that ~500 calories per day = 1 pound of loss a week, or 3500 calories = 1 pound of fat. Healthy weight loss is about 0.5-2 pounds a week, depending on your original body weight. I’m not a qualified nutritionist, so you should contact a professional before starting any weight-loss/gain plan.
Post/View Comments
Subscribe - RSS Feed
Walk Slow, Run Fast
Introduction
I’ve had to walk around quickly today, and it’s made me unhappy. I’m a rather slow walker – a leisure walker – to the point that people walking with me sometimes complain. Yet when I go running, no one wants to come along, even if I offer to jog at a slower pace. I’ve even seen Facebook groups decrying slow walkers – but more often than not, the people that walk quickly run slowly or even not at all.
I’ve thus decided that there are four main categories of people, outlined in this chart below.
Run Walk Categories
People in Category 3 and 4 are special cases, to be discussed later or never. In this post, I will compare Category 1 and Category 2 individuals. I will break this issue down into efficiency, time, attractiveness, and personal satisfaction.
Efficiency
Walking and running have different rates of efficiency. At slower speeds, walking is more efficient and at higher speeds, running is more efficient. This happens because walking and running have different methods of conservation of energy and momentum. Walking has potential energy and kinetic energy out of phase, and running has them in phase. To save time and boredom, think of walking like a pendulum and running like a spring. We can then compare power-walking to this following chart of the energy efficiency of walking and running, drawn from Life Sciences 2:
Run and Walk Efficiencies
At approximately 2 meters/second, running becomes more energetically efficient than walking. This converts to 4.47 miles per hour. From a less academic source, Wikipedia states that power-walking is between 4.5 to 5.5 miles per hour. This means that power-walkers are walking at a time when running would be more energetically efficient.
Thus we have a win for Category 2 (walk slow, run fast) – but what about the other aspects of this debate?
Walk Slow, Run Fast: 1
Walk Fast, Run Slow: 0
Time
Now how about time savings? It is true that if you are only looking at walking, then walking faster saves more time than walking slowly. But we must also consider the running part. Since you rarely see people running in their thick wool coats, we will consider running in terms of exercise.
Let’s first assume that we walk from Leverett House to the Science Center, round-trip, two times a day. The total distance traveled is 2.4 miles (0.6 miles x 4).
Walking to Class (0.6 miles)
If a power-walker speeds to class and back at a rate of 5 miles per hour (average power-walking speed), and a slow walker travels at merely 3 miles per hour, we can calculate that a power-walker spends 28 minutes, 48 seconds walking to class. The slow walker takes 48 minutes. The difference is 19 minutes, 12 seconds.
Now let’s say that both the power-walker and the slow walker hear from the popular media that exercising off or reducing consumption of food by 500 calories a day will lead to one pound of fat loss per week. While we must control for the increased speed of both individuals due to weight loss, let us assume that their diet plans are failures and despite their exercise, they maintain the same weight. The slow walker is now the fast runner, and maintains a brisk clip: a 6 minute mile. On the other hand, the power-walker is now the slow runner, and can only do 10 minute miles.
We can calculate calories according to my guide from an earlier blog post (http://darrenhe.com/blog/?p=71) using the Compendium of Physical Activities Tracking Guide [link]. Running a 6 minute mile (10 mph) has a METS of 16.0. With a weight of 70 kg (154 lbs), burning 500 calories requires 26 minutes, 47 seconds. On the other hand, running a 10 minute mile (6 mph) has a METS of 10.0. At the same weight, burning 500 calories requires 42 minutes, 51 seconds. The difference here is 16 minutes, 4 seconds.
The power-walker thus saves 3 minutes, 8 seconds after combining the time differences for walking to and from class with exercise time. However, in the course of a day, 3 minutes is insignificant. Furthermore, that depends on the weight of the individual and the number of calories desired. At a lower weight, running faster saves even more time; also, burning more than 500 calories will also tip the scales towards fast-running time savings.
I’ll have to call this one a tie, because the difference is very small and the margin of error is large. Let’s move on.
Walk Slow, Run Fast: 1.5
Walk Fast, Run Slow: 0.5
Attractiveness
What is more attractive, category 1 or category 2? This is a strictly personal preference, but there are some general social norms that we can look at. Let’s group this again by walking and running.
Walking: Walking quickly gives the impression that you are busy, important, and “going-somewhere.” You know the city you live in and you have no hesitation. Walking slowly, on the other hand, is characteristic of tourists, which tends to be frowned upon. However, walking slowly is also a characteristic of “cool” in urban America.
Running: Running quickly is hands-down more attractive than running slowly. Whenever I see a slow runner scrape by, involuntary twitches ripple across my face and I think, “Why even bother?”
Runner
Whether we rule this as a win for Category 1 or Category 2 is up to personal discretion. But since I live in Cambridge/Boston, being urbane is much more important than being “gangsta-cool.” Thus we have another tie.
Walk Slow, Run Fast: 2
Walk Fast, Run Slow: 1
Personal Satisfaction
What is more satisfactory? Let’s consider it case-by-case:
Walk Slow/Run Fast: Double satisfaction. The phrase “stop and smell the roses” is no longer applicable when you walk so slowly that the roses wilt while you walk by. You have time to say hello to your friends, listen-in on private conversations, and slow down traffic as a bumbling bystander. And when you go running, you feel the refreshing breeze across your body, wicking away your sweat. Your heart rate is higher, and you get that feeling of accomplishment after your run.
Walk Fast/Run Slow: Double failure. You accidentally walk by your friends without saying hello, you have to read about accidents that happened right next to you in the news, and you have to bump and jostle the homeless men as you scurry past them. Then when you go for a slow jog, sweat drips onto your arms and people look at you funny. No good.
Roses
Clear win for Category 2 (Walk Slow/Run Fast).
Walk Slow, Run Fast: 3
Walk Fast, Run Slow: 1
Conclusion
Walking slowly but running quickly is clearly superior than walking quickly and running slowly. Not only are you more energetically efficient, you are happier and will live a longer life (citation needed). While time savings and attractiveness of either option come in at a tie, Category 2 is still the overall winner. Thus I encourage you to slow down and smell the roses on the walk to class, and toast the other runners on your daily jog.
Winner!