Can carrying a few extra pounds of body fat affect your cycling performance? Why are the best cyclists in the world so skinny? Will being as lean as your body type allows, give you a big advantage in the hills?

Many cyclists spend a lot of money in making their bike a few pounds lighter but few make a real effort to lose excess body fat when they know they can. Having raced in Europe under team directors who have worked with CSC and Astana, I can speak from experience that professional cycling teams place a big emphasis on being as lean as possible, and what a rider should and should not eat, often times pushing it to the extreme. I remember my director pinching my legs or stomach and telling me I was too fat, or going through our trash for signs of left over candy bar wrappers.

Some of their beliefs on what one should and should not eat are unscientific and even unhealthy, but their thinking is that because a Tour de France champion did it 20 years ago, it must be the right way to do things… For example, I have been told that a banana takes 7 days to digest and should be avoided. When I was in South Africa recently, Robert Hunter told me how at Barloworld they insisted that he could not eat muesli for breakfast, his preferred pre race meal. Instead, they wanted him to eat pasta for breakfast. He stood firm and was the only one eating muesli for breakfast throughout the Tour de France. (He went on to win a stage and finish second in the green jersey competition).

Top riders will go to great lengths to lose body fat and even muscle they don’t need. Legend has it that Eddy Merckx went to bed every night during his career feeling hungry and Abraham Olano trained through lunch and ate only 2 meals a day throughout his racing career. The average rider does not need to go to such lengths to lose excess body fat, which at times may pose health risks. But a rider should be aware of the performance gains to be made by reducing body fat.

Weight is a key component of the performance equation. The other component is a rider’s power output (measured in watts). To determine a rider’s ability the standard measure is watts produced divided by the athlete’s weight (watts per kilogram).  A bigger, heavier rider will often put out more power than a smaller, lighter rider. However, when one takes into account the body weights of the riders, the smaller, lighter rider may have a higher watts per kilo.  

In terms of watts, is weight a big factor in performance cycling uphill? Here is a clear illustration of how important it really is. If you cycle up a 10% grad, a 2.2 lbs reduction in weight is a gain of 7 watts, i.e. if you are 2.2 lbs lighter than before you have to produce 7 watts less power at the same speed. 6.6. Lbs would be a gain of 20 watts (you have to produce 20 watts less power at the same speed), the difference between a good and a great rider at the pro level. 15 lbs is worth 50 watts - a gain one could not achieve if one trained 350 days a year!*

For uphill riding having a low body fat and a good power to weight ratio is very important. On flat roads this is not the case where bigger and heavier riders have an advantage over smaller, lighter riders. This is obvious when you watch the Tour and see the bigger riders like Boonen dominating the flat stages and the smaller riders like Contador dominating in the mountains. The reason for this is wind drag, and not gravity, is the main factor in performance on the flat. Wind drag is speed dependent (at twice the speed the force required to overcome air drag is eight times as great). Wind drag is determined among other factors by the frontal area of the rider, which does not differ greatly from small to big riders. As the bigger rider is often more powerful, he will be faster on the flat, even though his power to weight ratio may be lower than a smaller, lighter rider.

It should be noted that it is still a big disadvantage to carry excess body fat on flat roads. Excess fat does not help with putting out more power and is dead weight that has to be accelerated up to speed every time there is a surge in the pack. From my own personal experience I know that being 4 lbs lighter is the difference between average form and peak form. Many of my clients have seen significant improvements from reducing body fat. When I started with one of my clients, he weighed 175 lbs and was finishing 20 minutes back in the Norba semi pros XC races. With specific training, combined with reducing his weight to 150 lbs, he went from finishing 20 minute back to winning many of the series races and the overall championship title.

If you are serious about improving and know you are carrying extra body fat then it makes sense to try and reduce your body fat by changing some of your eating habits. Remember you are trying to reduce body fat and not lose actual body weight necessarily, although in most cases your weight will come down.
A body fat test will give you an idea of how much body fat you carry. A certain amount is needed to maintain good health. For men, 3% body fat is considered the minimum requirement, and 9% for women. However, to be safe, body fat percentages should not fall below 5% for men and 12% for women. Elite male endurance athletes will often be in the 4-10% range, elite women will be in the 10-18% range**.

So as you can see there is a wide range of difference even amongst top athletes. This goes to show that we all have different body types. Some are naturally lean, while others naturally carry more fat. Therefore, do the best you can with your body type to reduce excess body fat, and if you don’t want to sacrifice pizza night for going faster uphill then that is perfectly fine too!

References
*From Cycle Sport article “The secret of Bjarne’s success”, July 1997
**From USA Cycling Level 2 Coaching Manual