The mysterious “fat burning zone” continues to confuse many gym-goers. The theory goes something like this: working out in a “zone” of intensity that is less intense for at least 20 minutes will burn more fat calories than calories from carbohydrate. Is this true? Yes and no, but mostly no. You actually burn more calories from fat right now, sitting still, reading this post, than you do on the treadmill. That is because in the resting state, the body burns a higher percentage of fat calories. As you crank up the exercise intensity, you burn a little less fat per calorie. However, it really comes down to the total number of calories you burn per exercise session — if you want to lose weight.

Here is an example:

Let’s pretend for a moment that you decide power walk for 40 mins on the treadmill. This would burn approx. 5 to 6 calories per minute. After 40 mins, you will have burned 200 to 240 calories. Not bad. Percentage-wise, about 50% of these calories will come from fat, so about 100 to 120 calories.

Now, let’s say you decide to add running intervals to your power walk at a 1:1 ratio, meaning that for every bout of less intense cardio, you do an equal-length interval that is more intense. After 40 mins of this type of intense activity, you will likely have burned between 400 to 450 calories. A bit less fat is burned during intense activity, BUT, you burned more total calories. So, if 40% of those calories come from fat, you will have burned 160 to 180 fat calories!

This was a simple example of how interval training can turn up the calorie-burn. Try adding intervals to your current cardio routine if you want to 1) burn more total calories and 2) burn more fat!

I’m going off-topic today and will get back to the “Back” theme tomorrow. I have received so many questions about converting calories to fat  loss, converting Mets to relative VO2 (you guys are serious about your fitness, aren’t you?!), and how to figure out accurate calories burned per workout session, that I thought it would be a good time to finally address this for the masses.

I know many of you are addicted to your heart rate monitors, and if you have your height, weight, and age  plugged in to your watch, you will get a fairly accurate calorie count for your workouts. If you’d rather do this old school and learn a little exercise physiology along the way, go grab a sheet of paper and a pencil and let’s get busy with some math!

METABOLIC CALCULATIONS

Alrighty, let’s pretend you are working out on a stationary cycle that is older and therefore isn’t set up for heart rate tracking and calorie counting, and you don’t have a heart rate monitor, AND you desperately want to know how many calories you will burn during your 30-minute sweat fest…where do you begin?

• Begin with Mets (this is a setting on the machine)
• Multiply Mets by 3.5 to get your Relative VO2 max
• Mulitply Relative VO2 by your body weight in kg to get your Absolute VO2 (ml/min)
• Divide this number by 1000 to convert VO2 to L/min
• Multiply this number by 5 to get Kcal/minute
• Multiply this number by the total number of minutes you exercised to get the Total Kcal burned
• Divide this number by 3500 to get the amount of fat burned (remember, 3500 Kcal = 1 lb of fat)

Fortunately, most machines will do this math for you and also take into account your age. Some even account for sex (the kind you are, not the kind you do). A good heart rate monitor, as you can see, is handy, in that you never have to worry about whether the machine you are on is doing the right math, or even calibrated correctly. A HR monitor also calculates your calories all day long (as long as you wear it all day), so you can figure out how many calories you burn doing strength training, chasing your kids around, or sitting on the couch eating bon bons You will find you don’t burn many calories while sitting , but you already know that: 60 minutes of sitting x 2!  My 6 yr olds could do that math in their heads.

The interesting thing about calculating calories burned using Mets and VO2 is that you sort of get an idea how VO2 affects the body’s ability to burn fat. Read up on the important role VO2 plays in calorie burning: Target Heart Rate Training: A Formula For Success and why I scream and holler about maintaining your cardiovascular fitness: (Don’t stop now! 5 Reasons to stick with your exercise program

I’m addicted to watching The Biggest Loser (don’t worry, I’m gearing up for a loooong series of posts re: this show very soon – later this week, actually, so sit tight.) I love watching the massive transformation that takes place in a relatively short time. It is amazing, don’t you think? Off the show, people just like that are able to lose weight, and keep it off. They aren’t famous, of course, like the contestants, but they should be. Keeping weight off is HARD work. So how do they do it? I want to know, don’t you?

Fortunately, weight loss is a subject that colleges and universities spend a lot of time, and money, researching, which means the answers we seek are ripe for the picking, if you know where to look.

Cue Dr. Len Kravitz, Assoc. Professor of Exercise Science at The University of New Mexico. I’ve had the pleasure of attending a few of Dr. Kravitz’s courses at various fitness conventions, and I simply adore him. I knew he’d have the answers to this pressing question: How do you keep weight off successfully? It didn’t take long to dig up an article on the University of New Mexico website written by Dr. Kravitz. Kravitz summarized (thank you Dr. Kravitz!) the results from The National Weight Control Registry. It turns out, those who are successful at losing weight, and keeping it off, have specific traits and habits. This is what I learned…

Successful weight losers…

1. Make exercise a priority, and exercise more. According to Kravitz, women burn an average of 2,545 calories/week during planned physical activity. That is about 360 calories per day, or the equivalent of a thirty-minute run, or one-hour walk. The sad truth is, most people don’t exercise. In fact, in all of the states but five (Washington, Oregon, California, Hawaii, and Alaska), less than 18% of Americans engage in sports or exercise on an average day. (http://www.bls.gov/spotlight/2008/sports/pdf/sports_bls_spotlight.pdf)
2. Eat healthy 80% of the time (or more), making low-fat, low-calorie foods the mainstay of their diets. Also, participants in the registry noted that their eating patterns were the same on weekends as they were during the week. Weekends can ruin otherwise healthy eating patterns, so I’m not surprised to learn that successful weight losers try hard to stick to their usual, healthy eating habits. Although, 39% did say they followed stricter diets during the week. Those that ate consistently healthy all week long were 1.5 times more likely to maintain their weight loss during the following year.
3. They live a healthier lifestyle for themselves, rather than for another person, or to fit into a social norm. In most cases (85%), there is a “trigger” that sparks their weight loss journey, such as a medical condition (23%), reaching an all-time high in weight, or seeing a picture themselves. There were several contestants on this season’s Biggest Loser that said seeing a picture of themselves “shocked” them into realizing how big they had gotten, and motivated them to start losing weight. I have also noticed the shock on the contestants’ faces when the show’s doctor delivers the scary medical prognosis for each of them, if they don’t lose weight.
4. They weigh themselves frequently. Self-monitoring is key to reaching any goal, especially weight loss. Read “Successful Self-Monitoring: Log and Chart your progress” for tips on self-monitoring.

Bob's Red Mill Oatmeal

(And I added 3 of my own traits, based on health behavior change paper I wrote in college):

5. They eat breakfast every day. This is SO important. Although, I know many people who just aren’t hungry in the morning. I do wonder if, for people who this is the case, eating a regular breakfast would bump up metabolism enough that in time they would be hungry in the morning? I’ll research that bit some more. (Not sure what to eat? Check out the post: “The Best Breakfast is the one you’ll eat!”)

6. Don’t focus on the short-term effects of weight loss. Instead, they view the changes they’ve made as “lifestyle” changes that will last a lifetime. This part is really important. To keep weight off, a lifestyle change is key.
7. Watch less television. Think about it – not only is the sedentary behavior setting you up for a slower metabolism, but TV watching also promotes mindless snacking. And I suppose that for those who have to give something up in order to make time for exercise, TV is a logical activity to forego. Although, I have a dear friend that trained for a full marathon, on a treadmill mind you, by taping and watching her favorite shows while she logged mile after mile. I admire her focus. Even with my favorite shows to watch, I couldn’t stay on a treadmill that long, but I say, if it works for you, by all means, DO IT!!

IMPORTANT STUFF: According to the NWCR study, those who kept weight off for 2 years or more had significantly higher odds of keeping the weight off, reducing their change of “regain” by almost 50%!!

If you’d like to read the full article, here it is: Winning at Losing: Secrets of Long-Term Weight Loss

If you have successfully lost weight, please share your own Secrets to Success! Everyone struggling with weight loss or weight maintenance would benefit from hearing how others managed to pull it off, and keep it off.