Squats are a fundamental human movement as well as a resting position.
To build great strength, mobility and muscle you need to squat. For strength and muscle mass, squat with resistance; for mobility, squat deeply for time.
The Get Strong! program includes high bar back squats and deep front squats for building strong and muscular hips and thighs.
If you do back squats , you should do deep high bar back squats.
Deeper squats load the quadriceps and buttocks in their most stretched position, which results in greater muscle activation and loading.1 Deeper squats also take the knees through a full range of motion, which is important for maintaining healthy knee cartilage.2
Deep high bar back squats train the hips and thighs with less external loading than low bar back squats. A more upright posture and deeper squat translates to less external loading which puts less stress on the lumbar disks and knees while maintaining a high work load on the hips and quadriceps.2
I review the research in favor of high bar squats here.
By deep, I mean as deep as you can manage with a neutral spine. If you can't squat deeply I recommend working on squat mobility.
Front squats require a more upright posture than the back squat. As a consequence, deep front squats may be safer for the lower back and knees than back squats.5
In addition, the front squat may be superior to the back squat for training the lower back and abdominal muscles.6
Therefore I include both front squats and back squats in the Get Strong! program.
I recommend deep front squats because they develop more mobility than shallow squats, put less shear stress on the knees while training the cartilage through a full range of motion, put more load on the lumbar erector muscles, and require less external load resulting in less wear and tear particularly on the lumbar spine.
You must squat hard and progressively to develop your hips and quadriceps.
The Get Strong! Program includes both the back squat and the front squat.
1. McMahon GE, Onambele-Pearson GL, Morse CI, et al.: How deep should you squat to maximize a holistic training response? Electromyographic, energetic, cardiovascular, hypertrophic and mechanical evidence. Chapter 8 in Electrodiagnosis in New Frontiers of Clinical Research. http://dx.doi.org/10.5772/56386.
2. Hartmann H, Wirth K, Mickel C, et al. Stress for Vertebral Bodies and Intervertebral Discs with Respect to Squatting Depth. J Funct Morphol Kinesiol 2016;1:254-268. doi:10.3390/jfmk1020254.
3. DeFOREST BA, Cantrell GS, Schilling BK. Muscle Activity in Single- vs. Double-Leg Squats. Int J Exerc Sci. 2014;7(4):302–310. Published 2014 Oct 1.
4. Cappozzo A, Felici F, Figura F, Gazzani F. Lumbar spine loading during half-squat exercises. Med Sci Sports Exerc 1985 Oct;17(5):613-20.
5. Chow, J. (2009). A Biomechanical Comparison of Back and Front Squats in Healthy Trained Individuals. Journal of Strength and Conditioning Research, 23(1), 284-292.
6. Comfort, P., et al. An Electromyographical Comparison of Trunk Muscle activity During Isometric Trunk and Dynamic Strengthening Exercises. Journal of Strength and Conditioning Research. 2011. 2591), 149-154.