What makes runners naturally fast

Picking the right parents.

Genes

There’s a few factors!

Body proportions, some people (a large portion of guys) have large torso structure and small leg structure, while having longer more built legs and a smaller torso is much more efficient for distance runners.

Vo2Max: the amount of oxygen your lungs can use at a time, some people have a Vo2Max of 60+ trained by sitting on the couch all day and some people will never be able to get to a figure like 60 no matter how hard they train. Some people can improve their Vo2Max by 15 or so by training and some can only improve it by 5 if at all.

Muscle fiber type: a higher proportion of fast twitch and hybrid fibers will make you a very good power lifter/sprinter, I higher proportion of slow twitch fibers makes you a better endurance athlete. Most people just have a lot of fiber that isn’t really fantastic at doing either. This like Vo2Max is trainable but only to a certain extent. I come from a family of very good 200/400m runners on one side, and baseball and football players on the other side, and I’ve always been able to outlift my teammates by a ton and outsprint most of my teammates despite doing the same distance training they do. On the flip side I have teammates that will massacre me on tempo or high effort long run days that aren’t near me in the 3k and under.

Most high school distance training programs favor those that have a lot of talent in the Vo2Max/slow twitch department, as it’s usually 15-30 miles a week for most schools and lots of intervals. Their talent in those areas make up for the short comings in their training, while also working on the things they aren’t so talented at. I had a teammate that ran 51.5, 1:58, and 4:26 off of 15 mpw of horrible training. Everyone thought he was going to be a killer in college, he got a good buildup of 60-70 mile weeks and proceeded to run 2:00 and 4:24 after 2 years with a good program. At the end of the day, some kids are just massively talented. They have the perfect body type, a Vo2Max of 80, and have the speed and power potential to drop a sub 50 400m. That translates to having a stride that doesn’t demand as much effort, each breath can use way more oxygen, and they have naturally strong and fast muscles that help them move over the track.

The list is longer than you might think, but honestly it all falls under three headings...

1. genetics: tendons, VO2 max, limb proportion, muscle type, muscle mass, body type, lung volume, body composition, liver function, (lack of) allergies, height-to-weight ratio, blood volume, blood values, heart, etc.

2. Non-genetic factors such as environment & life circumstances: ability to suffer, dedication, focus, good coaching, training camps, racing opportunities, parental support ($$$), shoes, gear, elevation where they live now, elevation where they grew up, diet & eating habits, activity levels in childhood (and in adolescence), etc.

3. luck: didn't twist your ankle on the weekend before track season started, etc.

Interesting post, but I have a question: how does lack of allergies have anything to do with running talent? Maybe you're talking about immune function?

As a grandmaster runner i have seen a distinct difference over the years between runners that started early and ran HS Track over runners that started running in Mid 20's, 30's. The runners that picked up the sport late in life can make some nice gains but it seems they are way outclassed by those that competed in HS etc.

I guess that comes down to training the neuromuscular system very early and then not being able to train it to the same degree later in life.

You’re asking why does talent exist.

It’s the law of averages.
The average person will have the average response from training.
A talented person will respond better.
An untalented person won’t be able to keep up with the average person.

Most kids are capable of pushing themselves and many great runners didn’t attend training camps, live at altitude or have rich parents, etc.

When is a good time to twist your ankle? For most runners it takes less than a week to recover, anyway.

Besides genes, early childhood activity. If you weren't super active as a child, not much you can do now, but if you have kids keep them outside running and playing as much as possible if you want them to excel at sports.

I would agree that running track at a young age promotes good form. That said, what you describe is due more to selection bias than training effect.

Most adult onset runners have marginal top end speed. They struggle to break 70s for 400 at 40 and probably couldn't have broken 60 with training at age 18.

I know several guys who were on my hs track team who put the practice in but never broke 60/ 2:10/ 5:00/ 17:30. 20 years later they are reasonably fit adults who run 20 min 5ks or are mid pack Cat 3/4 cyclists.

Athletes with successful track backgrounds standout as master athletes for the same genetic reasons that they excelled at a young age-

1) Natural untrained VO2 over 60 (big heart and lungs with good muscle quality regardles of fiber type distribution)

2) Sustainable BMI under 20 (lean athletic build)

3) Reasonable coordination and athleticism. If you have #1 and #2 but not #3, cycling is a better option.

4) Tolerance for both sustained hard work (training dedication) and also ability to focus under pressure (racing instincts)

5) Individualistic personality. Runners, more than swimmers or cyclists, have to go it alone when needed in both training and racing. This is more of an innate trait than a trainable factor.

We’ve covered all this. It’s genetics. Read “The Sports Gene.”

Western African roots help.