Sloths Do this Longer than Dolphins

A sloth can hold its breath for up to 40 minutes by slowing its heart rate, while dolphins usually hold theirs for around 10–15 minutes.

When you think of animals built for underwater feats, sloths probably don’t come to mind.

But thanks to their famously slow metabolism, sloths can actually hold their breath for up to 40 minutes. That’s more than double what a dolphin can do — and dolphins are designed for swimming and diving!

So how do sloths pull this off? It all comes down to heart rate.

When a sloth holds its breath, it slows its heart rate by up to one-third. This lowers its oxygen use dramatically. Fewer heartbeats = less energy used = longer time before needing that next breath.

Dolphins, on the other hand, are fast, active, and need regular breaths of air to stay alert and agile. Their breath-holding limit usually tops out around 10 to 15 minutes, depending on the species and activity level.

It’s a great reminder that speed isn’t everything. In nature, sometimes the slowest creature wins — at least when it comes to oxygen conservation.

And get this: sloths don’t just win at breath-holding. They also sleep 15–20 hours a day, grow algae on their fur, and only come down from trees about once a week.

Slow, yes. But totally fascinating.

Try This at Home:
Hold your breath and count how long you last. Can anyone in the family beat 40 seconds? (Spoiler: You’re still not a sloth!)