Kettlebells are one of the best training tools for longevity—here’s what to look for if you’re buying them, according to Peloton’s top kettlebell trainer

Joslyn Thompson Rule has been a personal trainer for more than 15 years, so she’s used her fair share of weights in that time.

While she believes dumbbells and barbells have their place in any exercise routine, she says kettlebells bring something unique to the table.

“Kettlebells offer you a versatility that dumbbells don’t,” she says. “The shape of the bell challenges you [to move] in new ways—so you have to be a little bit more connected to the bell as you’re using it.”

So, I asked Thompson Rule for her advice on buying kettlebells and which weights to invest in. Here’s what she recommends.

Buy two or three different weights

Thompson Rule leads a series of kettlebell classes on the Peloton app. She says her routines often require three different weights: something light, something mid-range, and something heavy.

“For a beginner, I might suggest something like a 4kg, 8kg, and 12kg bell,” she says, which is roughly a 9lb, 18lb and 26lb spread.

Opt for a traditional shape

“Some companies have tried to get really creative with the shape of the bell, but how they were originally shaped is the best way,” says Thompson Rule.

Look for a kettlebell with a round-shaped weight, a flat bottom and a rounded handle.

Avoid kettlebells with sharp corners or unusual handles, as they can make exercises like the clean or snatch harder to do and more uncomfortable.

Stick to solid materials

You can buy a sandbag kettlebell, which can be handy to save space or to adjust the weight, but it might not be as durable as traditional ones made from metal.

If you want something that really lasts, Thompson Rule suggests going for cast-iron.

Protect your wrist with padding

If you’re new to kettlebell training, you’ll inevitably bash your wrists as you learn how to do certain kettlebell moves.

“Even if you’re just doing an overhead press with straight wrists—which is how you should do it—there is a level of pressure on your forearm and wrist from the bell,” says Thompson Rule.

The trainer often ties a bandana around her wrist to give it some cushioning, but you can wear sweat bands, which can work just as well as added wrist protection. Wrist guards are also available.

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