I happen to take great pride in my sweating abilities. Once or twice I have been embarrassed, but nothing feels better than the completion of a kick-ass workout accompanied by those “I feel so good neurotransmitters,” otherwise known as endorphins.

With all my heart pumping and sweat drenching, I wonder how many calories I’m torching. I know the gym machines always exaggerate, but by how much? Then—I received my belated birthday present from my dad—a Mio Motiva Petite Pink Watch! Can we say … exciting?!?

My Mio Experiment

The Mio is a watch that provides electrocardiogram (ECG) readings of your heart. All this means is that it has built-in sensors, allowing it to measure the electrical activity of your heart’s contractions. Simply put, the watch allows a pretty accurate reading of  your heart rate.

What’s even more exciting is that my Mio can track how many calories I burn during my sweat sessions.

With this knowledge I set out on a calorie burning experiment. I strapped on my Mio Motiva Petite Pink watch—what a name, huh?—and chronicled my workouts over the last few days. Note—I only used it when doing cardio.

Below are my results:

Machine Causing Me to Sweat Buckets	Time On Machine (minutes)	Calories Burned According to Machine	Calories Burned According to Mio
	60	7oo	500
	30	292	242
	20	232	215
	60	612	696
	60	915	597

As you can see, my Mio results were all lower than the machines’ estimate of calories burned. The elliptical-type machines were most “off.” Now, I know what you’re all thinking … “Well, how do you know your Mio is right?” To answer your question—I don’t. BUT, I do know that it is more accurate than the gym machines and that the results more closely match the rule of thumb for calorie burn—approximately 100 calories per every 10 minutes of heart-pumping, sweat-dripping exercise.

Just as the machines do, the watch asks for your age, gender, and weight and times the length of your workout. But, it also continuously assesses your heart rate, measuring your level of exertion. It then takes into account of all these factors, does some calculations, and finally, displays your “torched” number. Oh, how I wish it matched the machine’s number, that would mean a lot more chocolate covered raisins for me, but nop … maybe next time…

Now, my goal is NOT to parade my Mio—though I do adore the watch. But, rather to simply show that the machines in the gyms, particularly the “ski-like” ones, overestimate the number of calories torched. To more closely examine this point, I turn to one of my all-time favorite New York Times pieces by Ms. Gina Kolata, Putting Very Little Weight in Calorie Counting Methods. Kolata writes,

Claude Bouchard, an obesity and exercise researcher who directs the Pennington Biomedical Research Center in Baton Rouge, La., found that if, for example, the average number of calories burned with an exercise is 100, individuals will burn anywhere from 70 to 130 calories.

What Determines Your Exercise Burn?

• Level of exertion (aka are you barely blushing OR are you creating the next Niagara Falls?)
• Time exercising
• Calories burned per day, regardless of exercise (aka resting metabolic rate)
• Age
• Sex
• Size
• Body weight
• Body composition

What you do while on the machine also matters. William Haskell, an exercise physiologist at Stanford, explains this in Kolata’s article,

…with treadmills, the calories are not accurate if you hang on the bars. Hanging onto the rails reduced the number of calories burned by 40 to 50 percent. The same thing happened with stair-climbing machines.“I’ve seen people hanging on stair climbers who think they are doing 1,200 calories an hour,” Dr. Haskell said. “They probably are doing 600 calories an hour.”

A Message From Me to You

Ladies and gents—keep up those sweat sessions, just don’t take the calorie counts on the machines number for number—they’re not accurate. However, I must note that out of any machine, the treadmill is most accurate in terms of calorie counts.  BUT, keep in mind that not one “calorie counting tool” is dead-on, since there are MANY factors that determine how many calories your muscles are burning, and they just can’t be measured precisely by the average Joe or Jane in the gym. But, hey—if you have a device that can do this, ya better get on that … you’ll make a lot of moola.

Also—exercise to keep you feeling good and healthy. This is SO Important! (you know it is because I put it in red). Time and time again, it’s shown that those who exercise are happier, healthier, and more energized.  Remember—we’re in this to be Healthy Inside and Out!

Lastly, the nutrition in me must tell you this–just because you worked out, doesn’t mean you are entitled to a double serving of Ben and Jerry’s Phish Food ice cream . I hate to be the wind that ruffles your feathers, but it’s true. Think about it, if you run for 30 minutes, you torch about 300 calories—which equals about 25 wheat thins (yes, even the Multi-Grain kind) and a slice of cheese. Hence, it is important to still keep your nutrition basics in your mind’s forefront. To nab some workout fuel tips, read my post—Fooding the Fire.

Til next time, I will leave you with the words of Jillian Michaels (yea, I know she “sold out” with her line of “diet” pills, BUT you can’t deny that the woman knows how to work you out!),

Don’t forget you have to be smart about what you eat. Don’t erase all the work [you] did … by eating badly. Make sure that you’re eating healthy, staying focused on your workouts, and remember that this is about … being strong, being healthy and making time for you…

Want to get a better idea of how many calories you’re burning during your sweat sessions? Click HERE for a “Calories Burned Calculator.”

Happy Healthifying!

What are your thoughts on gym machine calorie counters?