Exercise Energy Expenditure - The importance of duration and intensity.

Exercise Energy Expenditure - The importance of duration and intensity.

Jun 2022
Exercise Energy Expenditure - The importance of duration and intensity.

Getting the most from your workouts means having a strong fuelling strategy, hexis uses your Exercise energy expenditure to calculate your unique Carb Codes and give you energy you need to fuel your performance. 

Exercise energy expenditure (EEE) is exactly what you think it is, the amount of calories you burn during your workouts. There are a couple of factors that change you EEE - what type of sport you are doing, how intense the workout is and how long you are working out. For example, generally speaking, playing rugby is going to burn more calories than doing yoga for the same amount of time, because the demands of each sport are very different. This doesn’t mean we should all play rugby to burn calories, it just means we need to change the way we fuel our bodies to match the demands of each sport. 

As well as the type of sport, we need to think about the intensity of exercise. The same sport done at a higher intensity will burn more calories, but higher intensity exercise can also change the type of fuel our body uses during our workouts. Along with burning more calories higher intensity workouts also use more carbohydrates during exercise, which needs to be considered when building a fuel plan. By understanding the demands of a sport and the intensity of a workout hexis is able to build a fuel plan that is unique to each person’s day and workouts. 

Knowing your Intensity 

So how do we make sure we give the correct rating of intensity when we’re adding a workout into hexis? There are a couple of easy ways to tell how intense your workouts are: 

  1. The “talk test” 
  • Intensity = Light: You can comfortably hold a conversation using short sentences
  • Intensity = Moderate: You answer questions with short sentences or three or four word answers, you are breathing heavier, but still relatively comfortable. 
  • Intensity = Hard: You can’t say more than one word at a time and are breathing very heavily. 

  1. Rate of perceived exertion (RPE) 1 to 10 scale
  • Intensity = Light: RPE is between 1 and 3 
  • Intensity = Moderate: RPE is between 4 and 6
  • Intensity = Hard: RPE is between 7 and 10 

Using these general guidelines give us a great way to consistently prescribe our training intensity in a way that is individual to each person’s level of fitness. 

Intensity and Duration 

In sports like marathon running or cycling where training can last for 2 - 4 hours the challenge of fuelling is often down to the duration of training more than the intensity. These longer sessions can have a very high calorie cost. Even at lower intensities 40 - 60% of the energy for these workouts will still come from carbohydrates which has a big influence on how your body needs to be fuelled. For these longer training sessions it's easy to fall into the trap of thinking that because the intensity is low or medium we don’t need as much energy or carbohydrate to fuel the session, but this is where things can (and often) go quickly wrong! 

Most of our workouts are different from one day to the next, some with higher intensity and some longer duration, as well as different types of training. This means that our fuel plan and calorie requirements also need to change day-to-day. By inputting your type of sport, intensity and duration of exercise you give hexis all the information it needs to create a unique fuelling plan for you for that day, and it may be completely different tomorrow because the demands you place on your body have changed, which means your fuelling should too! Discover how hexis adapts your fuelling to the needs of your workouts on our features page.

Dr. Sam Impey

Performance Scientist

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Dr. Sam Impey