Eli5: Newbie gains


Explain like I’m five, how do people new to working out get newbie gains? Why isn’t it just the same amount of progress per session for people who have been doing it for a long time?

In: 1

The short answer: **the human body has a maximum capacity for fitness.** You can’t just become endlessly more fit. The limits can be pushed, but only slightly — for example, the record for fastest mile doesn’t change all that drastically from year to year.

Completely linear growth isn’t possible with fitness. If it were, someone could simply work out every single day of their life and become _infinitely_ strong. But even the toughest Olympic athletes have a limit to their physical abilities — at a certain point, your muscles just _can’t_ get much stronger.

The more fit you become, the harder it is to become even fitter.

Your body starts to stabilize. When you first start working out, there’s a lot of room for growth — your body can improve in fitness pretty fast. But then it hits a point where it’s pretty capable of the stuff you’re asking it to do, and is starting to reach its maximum performance.

So the basic definition of “why”? Well, because human bodies aren’t capable of infinite growth.

A visual metaphor would be… I dunno, cooking chicken. There is a huge difference between how raw chicken looks when you put it in a pan vs. how it looks one minute later. There’s not much difference between how it looks after 5 minutes under heat vs 10 minutes vs 30 minutes. You can’t just infinitely make the chicken “more cooked.” It goes from raw to cooked to… a fairly consistent state of burnt-ness.

This metaphor is purely for understanding nonlinear growth, of course — fitness is nothing like cooking chicken, lol.

In addition to the other commenter, another factor is this: how strong you are is based on the amount of muscle fibers you have *times* the fraction of them that fire when your nervous system tells them to. Someone who hasn’t trained much gets less complete activation of their muscles than someone who’s been training for a long time. So part of newbie gains is thought to come from better recruitment of existing muscle fibers (which can happen quickly), rather than growth of additional muscle fibers (which happens more slowly).

The way I see it, newbie gains are the easiest portion of the fitness curve to achieve. Think of your maximum fitness possible to achieve with your genetics as all the fruit on a tree. Newbie gains are those low hanging fruit you can just grab from the ground without going to extreme effort. Once all the easy fruit is picked you have to do more and more work to pick the fruit that’s higher up and harder to reach.

Another factor to add is the metabolic requirements for gaining muscle. When you have someone new to working out, let’s say they have an average body with average bmi. So not big but not small. They are likely eating enough calories to build muscle. But if one consistently is lifting let’s say, the muscles over time will start to require more food to maintain and grow.

I’ll use my own self as example-
When I first started lifting I was preparing for a body building show. My muscles got big and nice quite fast, like a few months fast.

I took a break from heavy lifting for a few years and the muscle shrunk back and I returned to my normal body size.

Recently I started lifting again and I’m not making the visual gains like I did the first time, but I’m getting much stronger much faster.

Muscles don’t need to be big to be strong. But if you’ve not used the muscles before, they get big and strong fast. But over time it’s harder and harder to get bigger.

I have to eat a lot more food now just to make any real visible gains. I could keep lifting like I am and eating the same but I’ll more than likely loose body fat first and then potentially muscle mass if I don’t increase my food intake. And honestly it’s rather difficult to eat more than I am. So that’s a factor too!

What you will find is that basically everything in life has “newbie gains”.

It is much much easier to improve at the start of something, and then it gets progressively harder and harder to make improvements.