Which piece of strength workout equipment is truly better than the other? Here, pro trainers settle the kettlebell vs. dumbbell discourse once and for all.
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hands holding kettlebell inside circle - arm lifting dumbbell inside rectangle
Credit: Alex Sandoval

When you're ready to tear through a round of heavy goblet squats or single-arm chest presses in a crowded gym, you might pick up the first weight you can get your sweaty hands on — no matter if it's a kettlebell or a dumbbell. And if you're getting fit from home, you might simply be stuck using one type of weight during every single workout. 

But does the kind of weight you use for strength-building exercises really matter? Here, fitness pros break down the key differences between kettlebells vs. dumbbells, when each type of weight is most beneficial, and if you need to mix both tools into your routine.

The Differences Between Kettlebells vs. Dumbbells

Kettlebell vs. Dumbbell: Weight Distribution

Thanks to their distinct shapes, kettlebells and dumbbells have different weight distributions, says Allison Tenney, a certified strength and conditioning specialist with an RKC kettlebell certification in Austin, Texas. A kettlebell has a bell-like shape, featuring a ball flattened on one end and a curved handle on the other, so its weight is distributed right underneath the handle. A dumbbell, on the other hand, consists of a straight handle with two equally sized weights on each end, so the weight is evenly distributed, says Tenney. In turn, a kettlebell inherently provides less stability than a dumbbell, therefore it asks more from your body to keep steady.

This design difference is what gives kettlebells a slight leg up on dumbbells when it comes to improving your own stability, says Tenney. ICYDK, stability is about controlling a joint's movement or position. If your stability is limited, you may compensate your form when performing complex exercises, increasing your risk of injury or muscular imbalances, according to information published by the American Council on Exercise. 

Consider a shoulder press: When you're performing the exercise with a kettlebell, you'll start in a racked position, gripping the handle with your elbow tucked at your side and the bell resting on the outside of your forearm at shoulder level. As you press the kettlebell toward the ceiling, the weight of the bell will attempt to pull your arm out of alignment and away from your body. In turn, your core and arm muscles will have to double down to maintain proper form and joint stability, Prentiss Rhodes, a NASM-certified personal trainer and performance enhancement specialist, previously told Shape. Plus, the stabilizer muscles in your arm will be called on to keep your wrist in a neutral position throughout the entire movement, adds Tenney. Since a dumbbell has that evenly distributed weight, it's inherently more stable than a kettlebell, so you can bang out more reps with less work from your stabilizer muscles, she explains. 

Kettlebell vs. Dumbbell: Handle Shapes and Range of Motion

Another key kettlebell vs. dumbbell distinction is their handles — the shape and how that impacts your movement patterns. Since a kettlebell's handle is above the weight, it can accommodate two hands when gripped on the outside or the inside (think: positioning your hands in the free space between the bell and the handle), while a dumbbell generally has room only for one, says Tenney.

These differences are particularly significant when it comes to the power and range of motion you can achieve during certain exercises. The kettlebell's handle — combined with its uneven weight distribution — makes it ideal for ballistic exercises, such as kettlebell swings, cleans, and snatches, says Tenney. During a kettlebell swing, for instance, you'll use one or two hands to explosively swing the weight through a large arc of motion from the floor to your eye level, which helps develop power, according to research published in the North American Journal of Sports Physical Therapy (NAJSPT). As the weight falls back to the starting position (thanks, gravity), the muscles in your lower and upper body, as well as your core, will contract to slow the descent, turning the glue-building exercise into a full-body move.

While this swinging motion can be done with a dumbbell, it may not be as effective (or comfortable) due to the tool's equal weight distribution and straight handle, per the NAJSPT research. Simply put, "the shape and weight distribution of the kettlebell will allow for a more fluid, safer motion in most cases," adds Tim Kim, C.P.T., a certified functional strength coach and Equinox Tier 3+ Trainer. 

When to Use Kettlebells vs. Dumbbells In a Workout

To determine which strength-building tool you should incorporate into your workout, Tenney recommends first thinking about the goal of the individual exercise at hand: Is it strength, stability, or power?

For example, you can certainly build strength with kettlebells, but generally, "if you're trying to really build more strength and have more reps, the dumbbell is going to be something you're going to want to reach for versus a kettlebell since it's more stable," she explains. Similarly, dumbbells can be useful tools for building power and tackling ballistic exercises, but by and large, "choosing a kettlebell is going to be more beneficial because you're going to be able to really grip that handle as you're moving through a greater range of motion…[they're] really built to be moved around more dynamically." You should also consider which muscles you're aiming to target: If you're looking to target those stabilizer muscles, a kettlebell may be a better pick, says Tenney. (Related: The 9 Best Kettlebell Exercises for Your Upcoming Workouts)

Your experience with strength training may also help you decide which tool is best for your workout, says Kim. From his perspective as a trainer, it's typically easier for a beginner to learn how to use a dumbbell than a kettlebell, due to the latter's uneven weight distribution and unique shape, he says. On the flip side, Tenney says she typically starts her clients off with kettlebells if they're interested in Olympic weightlifting or a similar training style that involves a barbell. "When it comes to doing snatches and cleans and more of those traditional power exercises, I really like to teach the kettlebell stuff first because you can really get the mechanics down before moving into Olympic weightlifting," she explains. "It's a little bit harder to get those mechanics down if you were to use a dumbbell."

The Takeaway On Kettlebells vs. Dumbbells

In the kettlebell vs. dumbbell debate, there's no one clear-cut winner. "In my humble opinion, you can do all the same exercises with either of the two (yes, you can still swing a dumbbell)," says Kim. "With proper training knowledge and basic understanding of exercise selection, you can really do the same with both." To perform a kettlebell swing sans kettlebell, for example, you might hold the weight at one end of a dumbbell with both hands, rather than grip onto the straight handle, says Tenney.

Not to mention, both types of weights have their advantages, which is why Tenney suggests incorporating kettlebells and dumbbells into your strength-training routine. "If your program is all kettlebells, how can we find ways to just infuse the dumbbell in there….[so] you can get the benefits of both?" she adds. "To me, the more tools you have in your toolbox, the more fun training can be."