Before we get into the nitty-gritty of the findings, let’s take a moment to appreciate that this study aimed to look at cells. Yes, they were from actual people who did actual exercise, not just random cells being poked and prodded in a lab—but they’re cells all the same. It’s important that we look at how exercise affects our cells, because that’s the only way we can understand the mechanisms by which working out benefits our whole body. But it’s also important that we keep cellular findings in perspective. We can look at all the indicators of aging all we want, but if we don’t really understand how those indicators relate to lifespan, or to how good you’ll feel as an 85-year-old, it’s hard to draw meaningful conclusions from one study. Again, that’s not to say cellular findings aren’t important, it’s just that we have to keep them in perspective.