This text is from Racing Weight, Matt Fitzgerald’s confirmed weight-management program designed particularly for endurance athletes.
It’s the obvious motive. We’ve all felt the heaviness that comes with fatigue whereas operating or driving uphill. Swimmers which have to maneuver bigger limbs get drained extra rapidly, too.
Competitors for Oxygen
One of the vital essential underpinnings of endurance efficiency is the flexibility to ship oxygen to the working muscle mass at a excessive fee. As body-fat ranges go down, cardio capability goes up, as a result of muscle has much less competitors from fats tissue for oxygen and gasoline.
The first perform of physique fats, in fact, is insulation. An athlete’s skill to dissipate warmth is a vital efficiency consider all types of long-distance racing. Whereas this skill is partly a perform of the ratio of physique floor space to physique quantity, this ratio is smaller in larger athletes. So extra physique fats impedes warmth dissipation. It’s simpler to remain cool on an extended trip on a sizzling summer time day if you happen to’re very lean.
Fats-Burning vs. Carb-Burning
Certain, heavier athletes have extra mass to maneuver, however physique fats isn’t simply lifeless weight. Fats is a metabolically energetic organ that impacts train metabolism in essential methods that aren’t but absolutely understood. One factor we do know is that athletes with bigger quantities of physique fats burn much less fats and extra carbohydrate at decrease train intensities. For the reason that physique burns carbs throughout racing however can solely retailer small quantities of carbs, much less lean athletes will burn by means of their precious carb shops earlier than leaner athletes.
Lighter cyclists can speed up extra effectively. Good criterium riders are sometimes smaller riders who can match surges within the race extra rapidly than others.
Swimmers with heavier limbs have to make use of extra vitality to maneuver their legs and arms.
However small athletes are sometimes on flat programs. Why? Inertia and hydrodynamics.
In swimming, the quickest athletes are usually tall and rangy as an alternative of broad. Their narrower our bodies current much less frontal space within the water, making them extra hydrodynamic.
However Get This…
Extra fats hurts efficiency, however extra muscle is actually much more detrimental as a result of it’s much more dense, which is why we’re as unlikely to see a muscle-bound Tour de France winner as an overweight one.
However what constitutes extra muscle may be very totally different from what constitutes extra physique fats since muscle is the engine of motion whereas physique fats makes no contribution to endurance efficiency past offering vitality for low-intensity train. Even the skinniest runner carries sufficient physique fats to gasoline 24 hours of steady train.
Too A lot Fats Is Dangerous for Athletes in Many Methods
Not solely are top-level athletes fairly lean, but additionally physique composition is a superb predictor of efficiency in any respect ranges of endurance sports activities.