I am not, in general, a huge proponent of having one exercise be deemed “superior” to another. I think almost any movement that can be done safely, and can be “felt” in the targeted muscle fibers, can be effective for that person.
However, with that said, I do think there are “general” tips and observations that do apply to most of the population, for most movements done out there.
When it comes to squatting mechanics, though admittedly semantical to the naked eye, I have noticed some significant differences between the Kettlebell (KB) Goblet Squat and the Dumbbell (DB)/Barbell Front Squat, particularly in regards to quad recruitment.
While I am no physics expert, I will use some basic terminology to help illustrate what I have observed. In the KB Goblet Squat, the center of mass of the implement is a good 6”-8” from the torso for most individuals. Comparatively, for a DB Front Squat it is maybe 1” away, and for a barbell, even less as it rests ON the deltoids.
Given heavy enough of a load, this provides you with almost NO choice but to remain relatively upright, as the moment you start pitching forward, the ability to produce the force needed to keep the kettlebell in place (despite your best intentions) becomes insufficient, and the kettlebell falls to the floor. What is considered an acceptable amount of forward lean in a Front Squat or Back Squat, creates a degree of hip hinge that is often not possible with the KB Goblet Squat.
With a DB Front Squat, since one is able keep the center of mass relatively close to the body, this allows one to obtain more hip flexion, and with it, an increased “stretch” on the glutes. A good stretch means more activation. While I love a good debate and discussion about the place for ROM in strength training, for ME, I FEEL exercises more in muscles that can be stretched and taken through a full ROM. This would be very similar to foot placement on a Split Squat; a narrower stance TYPICALLY stretches the quads more, and the glutes less, making it a more effective movement for quad recruitment.
Am I saying that the Goblet Squat ONLY works the quads, and the Front Squat ONLY works the glutes? Absolutely not. However, what I am saying is that the devil lies in the details of execution, and the center of mass of the implement we are using relative to the movement arm (especially the hip) has a TON to do with where YOU will feel these exercises the most.
Matt Phelps