Runners everywhere have been churning butter on their runs — so I tried it and have some thoughts

Unless you’ve been sleeping under a rock (or spending your free time scrolling Strava), you’ve probably seen the viral churning-butter-while-running trend. It looks pretty simple — grab a carton of heavy cream, pour it into a Ziploc bag, add some salt, and head out for a run. In theory, by the time you return, you’ll have churned butter, ready to spread on your toast.

I’ve seen this trend all over my Instagram and TikTok for the past few months, so now I’m back training for another marathon. I decided to give it a try. In a heatwave, of course. I have some thoughts.

How to do it

I’m based in the UK, where heavy cream is known as double cream. But here’s where it gets slightly more complicated: in the US, heavy cream contains at least 36% fat, whereas double cream in the UK is richer and thicker, containing around 48% milk fat.

I’m no dairy expert, but I didn’t know if the higher fat content would make it easier or harder to make butter. According to Google, it would have been easier, and probably the better choice, but alas, my local store is in a black hole with no phone signal.

Instead, I grabbed two pots of whipping cream, which have the same 36% fat content. The next morning, pre-run, I put both of these into a Ziploc bag, sprinkled some salt in, then placed this bag inside another bag, inside my running backpack. What could possibly go wrong?

Right now in the UK we're experiencing a heatwave, with the temperature of my run a warm 32 degrees Celsius, or 89 degrees Fahrenheit. This might not sound like much to my readers on the other side of the pond, but I challenge you to exist in a world without air conditioning.

For anyone who cares, I was running in the excellent Asics Novablast 6 running shoes and tracking the run on my Garmin Forerunner 170.

I ran 10 miles with heavy cream in my backpack, and yes, it made butter (sort of)

I really wasn’t convinced this was going to work, and it sort of didn’t. I checked my cream/butter every few miles, and at three miles, I was still carrying cream. At five miles, the cream looked a lot thicker, and I was convinced I was on the way to having churned butter. By eight miles, it was thicker still, but I realized the second carton of whipping cream was probably too much.

Yet it seems all of this pulling the Ziploc out of my running backpack and putting it back in was where I went wrong. Both bags split at mile eight, and I had cream (or butter, you decide), running down my back and legs for the final mile and a half (I stopped early, for obvious reasons).

When I got home, I didn’t have anything resembling the butter you’d form into a block, like my runners on TikTok. I definitely had butter, but in the loosest sense of the word. Either way, I managed to spread it on some toast and have it for my breakfast. Once I’d put my entire outfit and backpack in the washing machine, that is.

My takeaway? This was a cool experiment, but next time, I’ll just grab some butter on my way home.

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