For people who don’t run competitively, running might seem like all one thing. But for those of us who do, we know that there are completely different types of runners, and your physical abilities will determine if you sprint short distances or run longer, endurance races. So whether you’re trying to find your niche, or just curious as to what determines our abilities, here’s how your build defines the kind of runner you are.
Whether we are better suited for sprinting or long-distance running is largely determined by our muscle fibres. There are two different types of muscle fibres, and each of us is genetically predisposed to have slightly more of one than the other.
Fast-twitch muscle fibres are those that don’t consume oxygen. Because of this, they are able to expand and contract much faster, but tire out much more rapidly also. This means that if you have more fast-twitch muscle fibres than slow-twitch ones, you will be far better suited to sprinting and short-distance running.
Those that do use oxygen are known as slow-twitch muscle fibres. The use of oxygen in these fibres allows them to endure exercise for much longer periods of time, but the speed at which they can be used is far lower than their fast-twitch counterparts. This makes people with more slow-twitch fibres better suited to run long distances as a moderate speed.
While we do have a genetic predisposition to either one or the other, the kind of training and exercise we perform will increase the proportion of either type. Over the course of years, training as either a long or short distance runner will cause the proportion to shift to a much more dramatic contrast. If the person training focuses far more intently on one style than the other, up to 80% of the muscle fibres in their bodies could eventually become either fast-twitch or slow-twitch.
Although we can’t really test our fibres to see how they’re divided, usually people who are conscious of this fact will decide to train to become either a long or short distance runner specifically. Others may decide to strike a balance so that they can perform equally well in either distance, although that makes it far less likely that they will excel as a runner. This is because, regardless of how much they train, they will only ever have around 50% of the right muscle fibres.
While it is possible for one person to partake in various kinds of running, the reality is that it means they are keeping their body generalised instead of specialised. This effectively caps their abilities, so the kind of runner you are built to be depends largely on what your goals are. If you want to win races, it would be best to choose one style and stick to it. If your goal is to be healthy and social, mixing is perfectly acceptable.
Your build with regard to running is something that changes gradually over the course of years, so it is advisable that you decide whether or not you want to specialise in one type of running. Another important factor to consider is that the type of shoe you should be wearing depends completely on the speed at which you run. To learn more about this, see our blog on Choosing the Right Sports Shoe.