The woes of survivorship bias in fitness

During WW2 allied engineers were tasked with retrofitting B-24 bomber planes with extra plating under the plane for added protection against ground fire. Their strategy was simple. As planes came back from bombing runs they would analyze where the gun and shrapnel damage was to determine where they would add the extra armor. Since armor was heavy they could only put it in key areas so they could still have enough fuel to go the necessary distance. The result of this logic didn’t result in more planes making it back safely and one could only imagine the amount of consternation this caused.

The problem with that line of thinking was that they were putting extra armor plating in places where a plane could take damage and return back safely. By analyzing the surviving planes there was an inherent bias. They eventually changed tactics and start analyzing planes that went down and using that data to inform where to put the extra armor.

Survivorship bias (or ‘silent evidence’ as noted by Nassim Taleb) is the idea of focusing on the entities that ‘survived’ some sort of process and unintentionally discounting those that did not. For example, for every hall-of-fame musician or athlete, president, or CEO there are legions of men and women who failed to achieve such exalted status. We interview, follow, imitate, fixate, and attempt to replicate these survivors. Their strategies are often the basis of advice-giving.

But are these pillars and archetypes of success the most well suited to design auspicious endeavors from? Or, perhaps, can we extract more value from learning from the throngs of people who don’t reach the apex of their endeavor and instead examine how they failed and the missteps they took. This alternate methodology for designing mechanisms of success could offer valuable insights into what not to do – often much more important than what to do.

Moving into the realm of fitness, there are athletes whose podiums, training plans and methodologies rise above others, fad diets rise and become bestsellers, and they become Instagram mavens who have more influence than Jack Lalanne.

And we are none the wiser to base our health and fitness strategies on what works for these individuals who likely were in exceptional and extenuating circumstances.

Essentially survivorship bias is a mechanism that highlights outliers. In the aptly named book Outliers: The Story of Success, Malcolm Gladwell writes:

The lesson here is very simple. But it is striking how often it is overlooked. We are so caught in the myths of the best and the brightest and the self-made that we think outliers spring naturally from the earth. We look at the young Bill Gates and marvel that our world allowed that thirteen-year-old to become a fabulously successful entrepreneur. But that’s the wrong lesson. Our world only allowed one thirteen-year-old unlimited access to a time sharing terminal in 1968. If a million teenagers had been given the same opportunity, how many more Microsofts would we have today?

Gates was in a perfect storm. A uniqueness that wasn’t replicable on a large scale. And much in the same vein as success in the fitness sphere, there is often an untold uniqueness that isn’t replicable – and – consequently, is often ill-suited for general advice-giving.