How do running genetics work

To understand the running genes, you need to understand how genes work in general.

There's no such thing as a single running gene, it's hundreds or maybe thousands of different genes that affect various running-related characteristics. And those genes can be dominant or recessive in both parents, producing even more possible combinations. On top of that, you have a separate set of DNA in your mitochondria, which also affects running. Basically, all that can be said is that if both parents are elite runners, their kids have a good shot at being talented, too. But it's not guaranteed, you may never know when some recessive gene from some muscle bound ancestor will pop up and spoil the potential runner :)

In the past there didn't seem to be many kids who tried running because their parents excelled at it. Now we have plenty of examples of athletes practically bred like racehorses.

ienjoyracing wrote:

What I don’t know, and what I’d like to figure out, is whether “talent” is the result of an average of the parents talent, or “strongest is most apparent” or a compounding effect of the parents talent. I’m not obsessed with breeding superior genetic runners, but I am curious whether I would need to marry someone athletic to have athletic kids, or whether my kids will have my athleticism as a baseline, and any athleticism on my wife’s part will just compound that, or if my kids will split the gap between our athleticism. So respond with any knowledge, experience, anecdotes or theories, or just with whatever your running family looks like, and we’ll amass an understanding of how it typically plays out.

Pure psuedointellectual speculation: If one assume that we can classify physiological potentials into phenotypes - Physiotypes then the question becomes one of how one can classify the inheritance patterns of different physiotypes. I begin separating physiotype into two well-known categories - response to training (shortened to response) and raw fitness state (ie being able to run 1:50 for 800 off of no training). It is well known that the fitness physiotype is more important for shorter distances/efforts and the response physiotype is more important for longer distances/efforts.

So we can say that each individual inherits a response physiotpye and a fitness physiotype. The response physiotype classifies the change of a state to a stimulus, while the fitness physiotype defines a trajectory through time in development space towards certain physiological states. The response of a network to stimulus is a property of the entire network itself, This would predict and continuum of possible response types characterized by the exact parameters of the network. The developmental trajectory in space is a function of the initial conditions (presuming the dynamic is indeterminate), so it is probably equally likely to be inherited from either parent. We could go a step further and say that the determinacy of the trajectory is a function of the parameters of the network controlling response physiotype.

A concrete prediction from this would be that distance running genetics are a mix of the genes of the parents and fast twitch/ are likely a random choice between the genetics of the parents, or arise due to random mutations. The last part would predict that middle distance runners arise randomly within the distance runner population.

So a sprinter could have one (or zero) parents who are talented sprinters while most very good distance runners probably come from two parents with the ideal genetic makeup. Distance runners come from distance runners and sprinters might come from sprinters, or arise randomly.

My favorite genetics scenario:

Fraternal twins, a boy and a girl. Both ran XC/Track, standard HS training schedules. Girl runs 16s in the 5K, gets recruited D1. Boy never breaks 19 and obviously doesn't run in college. I have no idea how athletic the parents were though.

For myself, my dad is a talented cyclist. He didn't run much but still broke 1:30 in HM. My mom was a decent jumper/sprinter. I got a blend, closer to my mom. I was good 400m-800m runner. Worse the longer the distance, even when I ran high mileage. My sister has no speed at all but is better the longer the distance, like my dad.

It varies and it's complicated. Running is a polygenic trait, so you generally inherit half of your ability from one parent and half from the other, but it also depends on the distribution of your parents' variant effect sizes. For example, if one of your parents has dwarfism or muscular dystrophy or whatever and you inherit that trait, then it's obviously not going to be a simple average. In addition, even if the distribution of effect sizes is relatively uniform, you generally inherit DNA in contiguous clusters, so you may inherit more running ability from one parent than the other. Finally, remember that there is a significant environmental component. For example, the first couple of google hits tells me that the heritability of VO2max is only 50%.

There’s obviously a lot of genes that’ll play a role, but here’s the things that can and usually are genetically passed down

-Body type

-Muscle fiber composition

-Heart efficiency

-Vo2MAX

-Height, specifically leg length compared to torso

-Muscular and aerobic adaptability

I feel I’m a solid example of this:

My dads brother has a 48.7 400m PB from when he was in highschool. My dad was a baseball player and was one of the fastest sprinters on the team. No one in that family is over 5’9

My moms family is full of taller people, not a very athletic family, but I imagine it’s nature over nurture, because my moms brother took up running in his late 30s and ran a low 2:50 marathon in his mid 40s despite being slightly overweight.

I am an 800/Mile guy, I’m 6’1 built pretty muscularly for a distance guy, and can run 53 in the 400m off of weights, mileage and strides, and can split low 50s when peaked. I’d imagine I got a little bit of both, but the role genes play is obviously there.

flvmmox wrote:

My favorite genetics scenario:

Fraternal twins, a boy and a girl. Both ran XC/Track, standard HS training schedules. Girl runs 16s in the 5K, gets recruited D1. Boy never breaks 19 and obviously doesn't run in college. I have no idea how athletic the parents were though.

For myself, my dad is a talented cyclist. He didn't run much but still broke 1:30 in HM. My mom was a decent jumper/sprinter. I got a blend, closer to my mom. I was good 400m-800m runner. Worse the longer the distance, even when I ran high mileage. My sister has no speed at all but is better the longer the distance, like my dad.

Wow I was just going to post how I remember reading somewhere that genes relating to athleticism tend to get passed down from the opposite sex parent. So males get their athleticism from their mother and and daughter from their father. And it looks like in your case they have. In my family too, my mother never ran, but her siblings did, and they were all sprinter types, either good football players or hurdlers, whereas my dad was a distance guy. I turned out to be a 400/800 guy, skewing mostly towards my mothers side, as would be expected.