IF THERE'S one piece of gym equipment you should have in your home gym, it should be dumbbells.

“There’s a reason dumbbells are in every single big-box gym,” says MH fitness director Ebenezer Samuel, C.S.C.S., who created an arm-focused muscle-building program, All Out Arms, based heavily around dumbbells. “If you want targeted muscle—and that’s what all guys want—then you want dumbbells.”

Even if you don't have an official home gym or workout area, the great thing about dumbbells is that they require little to no space—just as long as you're only working with one single pair of weights. That's easy if you invest in an adjustable set, which can shift from light to heavy with a quick turn of a knob or shift of a setting.

"When you're working out at home, space becomes your biggest challenge. You probably don't have enough room for an entire rack full of dumbbells (let alone the budget to buy an entire set of weights), so your best option is most likely going to be getting that whole rack in one set," says Brett Williams, NASM-CPT certified trainer and fitness editor at Men's Health. "Everything becomes simpler with these adjustable sets—from swapping in lighter and heavier weights mid-workout to storing your stuff when you're done."

Read more: Best Home Gym Equipment

With a pair of adjustable dumbbells, you can take your training to the next level without stepping foot in a gym, while also minimizing the amount of equipment you need. Just one adjustable dumbbell can replace up to 15 weights. Now that's what we call efficiency.

In the spirit of efficiency, we rounded up 10 of the very best adjustable dumbbells on the market below. Whichever set you choose, they're sure to help you stay fit and strong while training at home.

The most innovative dumbbells on the market, the iSelect’s rely on voice controls to change resistance. That means you can finish a set of bodyweight situps and yell to Alexa to switch to 25-pound dumbbells, then instantly grab your bells and start a set of curls.

Yes4All’s take on the adjustable dumbbell delivers up to 55 pounds of resistance and anti-rust plates that are built to last.

You don’t just get an adjustable dumbbell with up to 45-pounds of resistance; buy a pair of Bellitrons, and you can combine them to form a mini-barbell with up to 90 pounds of resistance. Even better, the Bellitron’s multi-position grips allow you to easily do dumbbell swings and other explosive exercises, too.

These Bowflex adjustable dumbbells have weights that adjust from 10 to 90 pounds in 5-pound increments, which replaces up to 17 pairs of dumbbells. They're also super easy to adjust; they have easy-to-use selection dials for adjusting weights that are smooth and user-friendly.

If you're in the market for some lighter weights, these Ativafit adjustable dumbbells top out at 27.5 pounds. With just a push and slide, you can easily change your weight setting in 2.5-pound increments.

An ultra-sturdy set of dumbbells that’s built for durability, making them perfect for heavy-duty moves like dead stop rows, Romanian deadlifts, and heavy presses.

This adjustable dumbbell set from Core Home Fitness lets you change weights in 5-pound increments just by twisting a handle, and ranges from 5 to 50 pounds. They also come with a lightweight aluminum cradle for a compact design.

These dumbbells from PowerBlock are welded from solid steel and have a powder-coated finish. This one set replaces 16 pairs of dumbbells for a total of 825 pounds of weight, and each dumbbell is expandable to 70 or 90 pounds per hand.

Each plate is 2.5 pounds and can be easily adjusted with the brand's quick adjustment system and convenient storage trays.

NÜOBELL's steel weight dumbbells adjust up to 80 pounds each and go up in 5-pound increments. They are super easy to adjust thanks to a click-lock handle that you rotate to choose your weight. The set also includes portable cradles for both adjustable dumbbells.

Read more: 13 Ways to Smoke Your Back Using Dumbbells

For the past two years, we consulted with Men's Health's Fitness editors and writers on the top weight adjustable dumbbell sets. Experts including our fitness director Ebenezer Samuel, C.S.C.S. and fitness editor Brett Williams, NASM, put countless adjustable dumbbell sets through the wringer to evaluate their weight capacity, performance, durability, and price point. We also considered top-reviewed adjustable dumbbells that had at least 100 five-star customer ratings on e-commerce websites that we trust.

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