What is an energy deficit?
First, let’s define an energy deficit. On one side, there is your energy expenditure: how many calories you burn throughout the whole day during exercise, at rest or even while asleep. On the other side, there is your energy intake: these are all the calories from the food and drinks you consume in a day. Put these two together and if you expend more energy than you take in, you are in an energy deficit. How is this important to cycling? Well, if you stay in a deficit long enough, your body will be forced to use some of its stored energy such as fat tissue or even muscle tissue, resulting in weight loss.
The role of power-to-weight ratio
One of the primary reasons competitive cyclists are interested in energy deficits is to improve their power-to-weight ratio. This ratio measures an athlete’s power output in watts (W) relative to their body weight in kilograms (kg). In cycling, speed is not only about the number of watts a cyclist can push, the weight of the cyclist and the bicycle play a big role in how fast they can go, especially when climbing or rapid accelerations are involved.
Energy deficit helped Chris Froome reach his full potential
Chris Froome is one of the most popular cases of improving power-to-weight ratio through an energy deficit. When Chris Froome turned pro in 2007, he weighed a bit over 75 kg and had a power-to-weight ratio of an average pro rider. He changed his diet and through a well-managed energy deficit reduced his weight to under 66 kg by the time he won his first Tour de France in 2013. He reached an elite power-to-weight ratio of 6,2-6,5 W/kg. If you want to read more about his diet, check out our previous article.
Improved climbing ability
Having a high power-to-weight ratio makes the most difference when climbing. Cyclists who are targeting Grand Tours, mountain stages or hilly courses have an extra incentive to push their weight lower. One of the most common uses for an energy deficit is to reduce body fat and become lighter without losing power. This is what allows GC contenders to be extremely lean when racing season starts.
Fine-tuning racing weight
It’s not easy or desirable to maintain an extremely low body fat percentage at all times. That’s why pro cyclists also use energy deficits strategically throughout the season to lose weight when it matters. For example, some cyclists might enter an energy deficit in the lead-up to a key race, ensuring they are at peak racing weight without compromising their training quality. An energy deficit is a controlled way for them to fine-tune their racing weight.
Recovery after illness or injury
When returning from an illness or injury that resulted in weight gain or loss of fitness, cyclists might also use an energy deficit to regain optimal weight. It has to be done carefully to ensure it doesn’t negatively impact recovery and training.
It’s easy to see that energy deficit can be very beneficial in a sport like cycling. But it’s important to keep in mind that it has its risks. We will look at its potential negative effects on health in the next article.
