USAWA

By Dan Wagman, Ph.D., C.S.C.S.

THE GUESSING GAME – BOX SQUATS

Part III: Removing the Guesswork

          Part II (see part II) of this series reviewed what was likely the first study to investigate kinematic differences between a box-squat-like movement and the standard squat. The next study was published by the Neuromuscular Laboratory at Appalachian State University in North Carolina in 2010.(2) They wanted to know what effect removing the stretch-shortening cycle via the box squat might have. They compared the box squat to the standard squat at 60%, 70%, and 80% 1-RM (1-rep maximum, the maximal amount of weight you can lift once). Their subjects were competitive male powerlifters with a minimum of 3 years experience and they looked at peak force and power during the concentric phase (i.e., ascent) along with relevant muscles’ activity. The squat was performed with a quick transition between hitting the hole and blasting back up and the box squat required a one second pause. The primary finding was that both forms of the squat were very similar, indicating that the box squat had “neither a positive nor a negative effect on squat performance.” This surprised the scientists because despite the one-second pause on the box, sufficient amounts of elastic energy remained available to negate significant differences between the two forms of squatting.

There are a few limitations that deserve mention. First, only a 1-second pause was investigated in the box squat. The usual recommendation includes times twice to five times as long. Perhaps the amortization phase requires more than one second to significantly lose its benefits. Second, the scientists did not define their box squat technique. It’s possible that the subjects held the position on the box firmly in an isometric contraction for one second as opposed to sitting back and resting on the box as is usually recommended. In doing so, the subjects would not have broken the coupling phase of contractions, which could explain why elastic energy remained to benefit the ascent.

A year later the same scientists provided additional information.(3) This time they also calculated peak velocity and made it clear that they removed the coupling phase. What the calculations revealed was that, generally, muscle activity was significantly higher in the standard squat compared to the box squat. This left the research team to conclude that, “It does not appear that the box squat, which removes the coupling phase, increases muscle activity in either the eccentric or concentric phase.” Based on their analyses they deduced that, “The box squat does not appear to be a viable alternative to squatting…which would not optimize training adaptations.”

A Final Look

The most recent study was published in 2012.(4) This research is very complex in terms of the kinetic variables investigated and results analyses and interpretations. I’m limiting my review to those aspects most related to the comparison of the box squat to powerlifting squat.

The research team used 12 well-trained powerlifters with an average training experience of 9.2 years. The testing protocol I shall present is the one with the heaviest weight, i.e., 70% 1-RM. Though 30% and 50% 1-RM were also investigated, I’m omitting those findings because, 1) although of great scientific value, those intensities don’t reflect the training most strength athletes engage in; 2) by including findings at lesser intensities, the math is skewed away from the higher training intensity; 3) since research shows that the degree of muscle involvement can change as lifting intensity rises (1), I thought it prudent to only look at the heaviest weight lifted (see Part 1).

The scientists looked at the traditional squat (weightlifter’s style), powerlifting squat, and box squat. The box squat employed the powerlifting squat style along with sitting/rocking backward on the box as is mostly advised in the gym setting. Each subject paused on the box for the same duration used in training, which ranged from 1.3 to 2.3 seconds. All conditions required the powerlifters to squat as explosively out of the hole as possible.

One of the most interesting findings was that the forces generated in the box squat were the weakest. The same was found for peak power values; the box squat came in last. In terms of speed of movement, the traditional squat was superior to the powerlifting squat and the box squat came in last. Although mathematically insignificant, I thought I’d share it with you because perhaps you might still consider that meaningful. In regard to the rate of force development, however, the box squat showed values three to four times greater than the other squat techniques. Another important finding was that the greatest hip moments were observed in the powerlifting squat and the least in the box squat. The same comparisons were found for the lower back and knees.

Another important consideration is that during the weightlifting and powerlifting squat, large increases in force were measured during the transition in and out of the hole. During the box squat, however, these forces decreased tremendously, though they would “then rapidly increase during the concentric phase.” This is expected, and nice to have scientific confirmation for, since you’re starting a squat out of the hole from nothing. Of course this also highlights how ineffective the box squat would be for improving standard squat abilities because a critical performance component of the latter is removed from the movement.

Finally, in looking at joint angles of the hip, knee, ankle, and shank, significant differences were noted between the box squat and powerlifting squat. This, too, is an important consideration when it comes to training specificity, one of the key variables required to maximize training gains. With a significant difference between joint angles in these two squat movements, even though the subjects were instructed to copy their powerlifting squat style to the box squat, it’s not clear how the box squat would be able to increase performance in the powerlifting squat.

This group of scientists noted that one of the key findings of previous research is that if you can maximize the production of all of the variables this group looked at, you would provide your body with the best stimulus necessary for long-term strength gains. Rather clearly, the box squat would not be able to deliver.

The next step is to tie the research together and derive at a conclusion. Part IV will attempt to do so.

References

1. Król, H. and A. Golaś. Effect of barbell weight on the structure of the flat bench press. Journal of Strength and Conditioning Research. 31(5):1321–1337, 2017.
2. McBride, J., et al. Comparison of kinetic variables and muscle activity during a squat vs. a box squat. Journal of Strength and Conditioning Research. 24(12):3195-3199, 2010.
3. Skinner, J., et al. Comparison of performance variables and muscle activity during the squat and box squat. Journal of Strength and Conditioning Research. 25(Supplement 1):S21, 2011.
4. Swinton, P., et al. A biomechanical comparison of the traditional squat, powerlifting squat, and box squat. Journal of Strength and Conditioning Research. 26(7):1805–1816, 2012.