Repost from 2018 (because it still applies and I still hear people touting “the best equipment”):

I had a call from someone inquiring if we offered kettlebell classes. He was disappointed to hear that we didn’t offer that class nor use kettlebells in our personal training. In spite of trying to explain that we could replicate almost every exercise with a dumbbell, it was a deal breaker. This post is going to give you the scoop on a lot of the trendy pieces of equipment out there.

Let’s start with external loading, meaning something that has weight that is outside of your body. This includes everything from a dumbbell to your grocery bag.

All things are acted upon by gravity (this is what gives it weight) and gravity’s force is perpendicular to the ground. This is why we need multi-angled benches in the gym. In order to change what muscles or area of muscles we are working, we have to change our body position since the direction of the force of gravity is fixed.

Your muscles do not know what you are holding. It only senses that what you are holding has weight. Your grocery bag could indeed be your workout tool. That said, there are kettlebells, sandbags, medicine balls, BodyBars, sledge hammers, tires, etc. all trying to be the next big training tool. So, what is the deal with all of these workout tools?

They are all external loads with just some minor differences.

Kettlebells: It’s a weighted ball with a handle on it. There a few movements that have a unique advantage because the leverage when held with the “ball” resting on the forearm or when inverted with the “ball” above the handle. Other than that… it’s just a weight.

Sandbags: Think, a sand weighted duffle bag. It’s a weight that shifts and can be thrown around and slammed down without damage. Other than that… it’s just a weight.

Medicine Balls: Weighted balls that can be lifted, thrown, and slammed. Some bounce a lot, a little, or not at all (depending on the style). … it’s just a weight.

BodyBars: it’s just a padded, fixed weight bar…

Sledge-Hammer: It may be a regular sledge-hammer, or maybe a fancier (more expensive) version, which, in essence, is simply a handle with a weight on one end that you can swing around or slam down. Because of the leverage, it offers some slight variation in some movements. But, all in all… it’s just a weight.

Tires: These are typically discarded truck tires (although you can buy some really fancy ones) and are almost strictly used for flipping. OK, again, there’s a leverage issue that’s a little different from, say, doing a deadlift, but only a little. Once again… it’s just a weight.

Now, I’m the first person to say that I love my toys. I love having a variety of implements. I love them because they offer a psychological change for clients, not because they offer a real physiological one. What my point in this whole thing is, is that external loads are mostly all the same and you shouldn’t believe any hype about “X” being the “best” way to train. Buckets filled with water, rocks from your yard, indeed… grocery bags could all be just as effective. Just lift things up and put them down. (Hmmn? that sounds familiar) 😉