By John Krueger (About the Author)
Squatting movements should be included in every single workout routine, no matter the goal. The two most common variations are the back squat and the front squat. In this case the back squat refers to a barbell squat (or a variation) where the weight is loaded on the posterior (typically upper back/trap area) of the lifter. The front squat refers to a barbell squat (or a variation) where the weight is loaded anteriorly or in front (typically across the shoulder/clavicle area) of the lifter. While they both share several similarities, I plan to discuss some of the differences that are either not well known, or skewed by bro science and opinions.
One of the biggest differences between front squats and back squats is the variation in mobility required and eventually inherited from each exercise. The new fab in fitness these days is low bar back squats, which in a lot of cases becomes more of a back extension/squat hybrid. Even in old fashion back squats, the lower back can aid to your lift. This is one of the reasons why people can lift more weight with a bar on their back than on their front. In my opinion this is why so many people make the front squat second fiddle. In order to perform a front squat with proper form; great mobility is required in a multitude of ways; significantly more than what is needed to preform a standard back squat. Hip mobility is also important in order to squat to proper depth while maintaining your knees in alignment with your toes, also ankle mobility to prevent your lower back from rounding. Upper back (or thoracic spine) mobility is need to keep your chest and torso vertical. Wrist, and shoulder mobility in order to un-rack, hold, and re-rack the weight. If you do not have the mobility needed to perform a front squat with a standard clean grip, consider using a cross armed grip or even Frankenstein/no handed grip. While the added mobility needed will limit the weight you can lift in the beginning, the immediate health benefits of being able to move better are worth it.
2. Muscle Recruitment
The popular opinion regarding the two is that a back squat is more posterior dominate (lower back, glute, hamstrings) where as a front squat is more anterior dominate (quads). While this is true to a certain extent, there is a very minimal difference between the two. Both movements recruit all of the same muscle groups, and mostly to the same degree. However it could be argued that your core is harder at work during a front squat do the need of keeping your torso upright throughout the duration of the movement. In other words, one version is not necessarily better than the other if your goal is to build muscle, instead it comes down to personal choice of which exercise you enjoy more.
The biggest difference between the two is most likely the amount each movement has on strength. Back squats allow for more weight to be used than front squats do (Take a moment to think about the amount of people you see back squatting 315 on the internet vs the amount who front squat it). Squatting with the bar across your upper back provides much more support for heavy loads than front squats where the weight is supported by your shoulders. Back squats are better suited for heavier weights, and with more weight comes greater potential for gains of strength. However it can be argued that due to the added mobility/flexibility needed for front squats that they provide more functional strength. This is why power lifters/bodybuilders typically stick to back squats as their main lift, and use front squats as an accessory movement; where as athletes will use front squats as a main lift in addition to back squats in some cases.
IN CONCLUSION: Both squat variations have a place in almost everyone's routines/programs. If you have only ever done one type, or mostly stick to one type then I would suggest adding some variety into your workouts. For example you can alternate back and front squats each session. If you are an athlete or have interest in better overall mobility/flexibility i would suggest using front squats as your primary squat variation, while supplementing in back squats in heavier loads/ lower rep schemes to work on strength. If your goal is strength then i would use back squats as your primary, while supplementing in front squats periodically but also making an effort to add in more mobility/flexibility exercises on the side.