Using your Powermeter for Weight Loss
Frank Overton
Did you know you can use your powermeter to help with your weight loss goals?
It's true! The amount of "work" (watts) you throw down during a workout can be translated into kiloJoules (kJ) or calories burned. For example, a 1 hour ride that yielded 600 kiloJoules of work equals ~600 calories or about one Chipotle burrito bowl. Ride for 5 hours and 3,000 kJ's or 3,000 calories...that's a lot of food! No wonder cyclists always think about food on long rides! It also kinda gives meaning to Eddy’s famous quote, “ride more, eat less” eh? You still want to Win in the Kitchen!
To execute hard/long workouts and to feel good during them, it is important that athletes fuel properly. This means not only eating enough calories, but also enough carbs to match the demands of their working muscles. Think of carbs to an athletes muscles as what high octane gasoline is to a Ferrari. Without the right kind and the right amount of gas, neither will be going fast for very long.
So then how can an athlete manage to lose weight if they need to fuel hard rides? The key is to ensure enough carbs and calories are consumed during and immediately after training and then to cut back on calories at other times of the day. For example if you train in the morning, then you should eat breakfast about 1.5-3 hours before, consume 30-60g of carbs per hour during your workout if will last longer than 75 minutes or 60-90g for rides >3 hours at race pace and eat your recovery meal within one hour after you finish. This will ensure that you don't bonk, that muscle glycogen stores are maintained and that you support muscle growth and repair. Calories at other times of the day, such as your snacks and dinner is where you would aim to cut back on calories in this case. A great way to do that is to have a big dinner salad! We like to call that your "Bowl of Health."
How many calories do you need? How much should you cut back to lose weight?
To determine how many calories you need per day, you will need to calculate your RMR (Resting Metabolic Rate). Hence the word "resting," RMR is the amount of calories you need to simply survive (think heart beat, brain activity and respiration) and it doesn't take into account any activity. That is where BMR (basal metabolic rate) comes in. BMR takes your RMR and multiplies it by an activity factor (AF) that takes into account your daily activity. The AF for sedentary individuals, like those working a desk job, is 1.2. But the AF for an extremely active athlete can be as high as 1.9. However this AF is only a rough estimate and is not nearly as accurate as using your powermeter to measure your calorie burn!
When the goal is to lose weight, we suggest you calculate your RMR using an online calculator, multiply it by the 1.2 AF (to take into account normal daily activity) and then add in the amount of kJ you burn during training. From there subtract 250-500 calories, which will result in a 1/2 lb to 1 lb weight loss per week.
An easy way to determine how many kJ you burn is to look in your TrainingPeaks at a week with your typical training volume/intensity and divide the total kJ for that week by 7. Here's an example. For this athlete, they would need an extra 650 calories per day (4479 kJ/7 days per week) in addition to their BMR (with AF of 1.2) to maintain their weight. If their BMR (1.2 AF) was 2000 calories, then to lose weight this athlete would need to eat about 2150-2350 calories per day to lose 1/2 lb to 1 lb per week.
Let summarize:
(RMR x 1.2) + (kiloJoules burned during exercise) = BMR or Daily Calorie Needs to maintain body weight
Daily Calorie Needs - (250 to 500 calories) = 1/2 to 1 lb weight loss per week.
Note: 1 lb = 3500 calories
How many calories am I eating?
All food, whether it’s a donut or a plate of pasta, has a caloric value. You can figure it out by looking at the values printed on the back of food labels (pay attention to serving sizes) or by looking up the food in an online food database such as MyFitnessPal.
Long Term
By cutting back 250 to 500 calories per day, you can expect to lose 1/2-1 pounds per week. Remember though, consistency is king so don't let one day of breaking even or going slightly over discourage you. Over the course of 8-10 weeks or more, the small changes you've made will translate into noticeable changes in your body composition and improvements to your overall health. We firmly believe that besides increasing your power output, Winning in the Kitchen is one of the single greatest changes you can make to improve your cycling performance. So what are you waiting for? It is time to start #winninginthekitchen!
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