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Sunday, November 17, 2019

Dr. Aaronson Helps you Convert Watts to Calories to Make Sense of Your Stationary Bike Workout

Dr. Aaronson rides his stationary bike for an average of 1 hour at an average Wattage of 104 resulting in 374 calories burned.

Power has become the holy grail of assessing your bike workout. That's the metric that propels you forward when you use games like Rouvy and Zwift.  But what does that mean in terms of energy expenditure with respect to calories?

If you are exercising to lose weight and become healthier, calories burned during your routine may be of importance to you. I enjoy using online apps such as Rouvy, Zwift, and Trainer Road not only to help me achieve my exercise goals but also to prevent boredom. An example: TrainerRoad can provide an average power and give you the total time of your bicycle ride which can be plugged into the above online calculator to help you easily calculate calories expended.

Here is the link to the Watts to Calories Converter Calculator. I find this link so helpful, I bookmarked it myself for my own personal use!

Here is the calculation if you prefer to do your own math:
energy (kcal) = avg power (Watts) X duration (hours) X 3.6

So let's do some math to see if exercise in addition to dietary restriction helps with weight loss.

  • There are 3500 calories in a pound.
  • If you exercise at 100 watts for an hour 5 times a week, you will burn approximately one pound every 2 weeks: 374 calories times 10 sessions equals 3740 calories.
  • To lose weight, you must control your food consumption. There are multiple strategies to do this.
  • One strategy is to use a system like MyFitnessPal to help you track your progress (see my link Wearables, Apps, and Weight Loss. How Much Weight has Dr. Michael Aaronson Lost? to learn more). This approach should help you start losing weight over time, as your doctor may have prescribed.
  • If you increase the intensity of your workout, you will burn your calories quicker. For example: if you average 150 watts an hour you will burn 540 calories an hour.
All of this said, please remember to pace yourself when exercising. If you get injured, you will not be able to exercise at all.  Safety first!