Biceps and Goodhart's Law
Biceps have come to represent strength since they are the only part of the male body that can become muscular, and where such muscle can be shown off while wearing "polite clothing"!
If there is one thing that screams “gym bro”, it is bulging biceps, jutting out of a short-sleeved shirt/t-shirt. If the owner of these biceps is an “extreme gym bro”, it is possible that these biceps are huge, and supported by relatively tiny shoulders.
It’s not just about gym bros. The emoji for “strength” features a flexed bicep. When we ask a child to show its strength, it usually flexes its biceps. So why have flexed biceps become such a symbol of strength, even if they may not alone correlate well with absolute strength (after accounting for impact of shoulders, back, glutes, etc.)?
The answer is Charles Goodhart’s Law. Which states that “when a measure becomes a target it ceases to be a good measure”. Or I like it’s corollary which says “when a measure becomes a target, people will start optimising for it, and it thus loses relevance as a measure”.
What distinguishes biceps is that they are one part of the body that can become visibly muscular, and whose muscles can be shown off while wearing polite / conventional men’s clothing.
Biceps can be shown off while still wearing polite clothing, unlike pretty much any other body part that becomes visibly muscular
Think about it from the male perspective - you may have great abs but the only way as a man to show them off is by being topless, which is NOT polite (women can still show them off while wearing extremely formal saris). To show off your quads or hamstrings, you need to wear short shorts. Shoulders and traps and lats need sleeveless tops - which is mostly sportswear / home wear for men. Yes, you can wear tight t-shirts to show off your chest, but again I don’t know how “polite” that can be.
So that leaves the bicep, which can be shown off while wearing short-sleeved shirts while still looking fairly formal. This means that if you are a muscular man, pretty much the only way to show most people that you are muscular is to show off your biceps!
Now let’s go into a bit of (hypothetical) history. Let’s go back to the time before most modern gym equipment had been invented. The only way you would get strong was by lifting or moving heavy weights. And if, this way, you were to build yourself a strong upper body, you would by corollary also build big biceps. That direction of causation is pertinent.
Consider the set of all conventionally strong men wearing polite clothing. The only part of their musculature that would visibly be seen would be their biceps! Consequently, strength started being correlated with the size of one’s biceps.
Until it became a target! (invoke Goodhart’s Law!)
A weak man would see strong men with big biceps (and not see the strong man’s big shoulders or back) and assume that the way to get strong was by building big biceps. Another weak man would notice that the size of shoulders or back or ass didn’t matter - as long as you built your biceps, people would consider you to be strong.
By now, gym equipment training specific parts of the body (such as the Nautilus) had been invented, and this allowed you to isolate and train your biceps. And that is precisely what millions of “gym bros” around the world still do - unless you are at the beach (or the gym itself), the only part of your musculature you can normally show off is the bicep, and so you just optimise for it!
So as the bicep became a measure of one’s fitness, it became a target. And once it became a target, people optimised for it and (at least in my eyes) it has ceased to be a good measure of someone’s visible strength.
Of course, someone with big biceps is strong if they also have big shoulders and chest and back, but controlling for the latter, the size of one’s biceps have little to do with one’s strength!
On my part, when I now see someone with big biceps I quickly look at their shoulders as well (assuming they’re not wearing a very loose top). If the shoulders look small relative to the muscles, then I immediately judge them as “gym bro”!
This is a nice tweet casting shade on a “gym bro”!
When you do push downs, the part of the tricep that becomes big is the one closer to your elbow - which can be seen outside a short-sleeved shirt! If you’re only doing compound lifts (including overhead presses and pull-ups) triceps first get bigger closer to your shoulder - which is useless when it comes to showing off!
PS: None of what I’ve said in this blogpost applies to women. And from what I know, big biceps aren’t a thing among “gym sis’s”.
Do we need to invoke Goodhart's law for this? It's simple vanity, isn't it? The way being thin was considered a sign of attractiveness.
Haha! In Kolkata, there is an influx of men coming to the gym before Durga Puja. I remember my gym trainer friend telling me that most of them want to build big arms. And it was frustrating for him.