Grouping Swim Races Into Families

Hey swimmers! This is coach Milo.

Welcome to another Q&A session where I answer questions from you all on the internet.

Today's question is:

"Grouping Swim Races Into Families"

Summary:

Asked how he'd group swim races into families, Milo answers through the lens of body type and muscle fiber. Sprinters, like 50 swimmers, need more power, more physical strength, and height is an advantage, while at the opposite end, distance and open water swimmers like the 1500 or 1650 carry far less muscle definition. More muscle means more power but a greater energy cost, and distance swimmers trade that power for the ability to swim long. He digs into the physiology: fast-twitch fibers come in type A and type B, and everyone is born with a fixed number of fast-twitch fibers they can't change. Type A is what you're born with, while type B is adaptable, joining the fast-twitch family if you sprint a lot, or shifting toward slow-twitch if you train slower and longer.

Answer:

Here's the deal. If you're a sprinter, say a 50 swimmer, you're going to want a lot more power and to be a lot stronger physically, and if you're taller, that's an advantage. If you're on the opposite end of the spectrum, like an open water swimmer or a 1500 or 1650 person, you're going to have a whole lot less muscle definition. Just know that the more muscle you have, the more power you can produce, but it comes at a greater cost of energy. On the flip side, if you swim longer distances you don't need that power, you need to be able to swim for longer periods. So really it comes down to how you train your body and whether you have more fast-twitch or slow-twitch muscle fibers. Fast-twitch fibers come in two types, type A and type B. Everyone is born with a fixed number of fast-twitch fibers, and you can't change this. Fast-twitch type A is what you're born with, and everyone's got a different amount, which makes some people better suited for sprinting and others for longer swimming. But fast-twitch type B is adaptable: it becomes slow-twitch if you don't sprint very much, or it joins fast-twitch type A if you sprint a lot. So type B joins type A if you swim and sprint a lot, but if you swim a whole lot slower in practice, that type B joins the slow-twitch family, which enables you to swim for a longer period of time.