Squats vs. Deadlifts: Which One Builds More Leg Muscle?

Squats and deadlifts are two of the most fundamental compound exercises in strength training. Both engage multiple muscle groups and are often central to powerlifting and bodybuilding routines.

However, when it comes to building leg muscle, which exercise reigns supreme? This article explores the biomechanics, muscle activation, hypertrophy potential and scientific literature to determine whether squats or deadlifts are superior for lower-body muscle growth.

Biomechanics and Muscle Activation

Squats: A Deep Dive

Squats primarily target the quadriceps, hamstrings and glutes, with secondary engagement of the calves and core. A study by Escamilla et al. (2001) analysed electromyographic (EMG) activity in different squat variations and found that back squats highly activate the quadriceps, gluteus maximus and hamstrings.

The depth of the squat also plays a significant role; deeper squats lead to greater muscle activation, particularly in the glutes and hamstrings (Schoenfeld, 2010). The bar placement influences muscle engagement, with high-bar squats favouring quadriceps activation and low-bar squats increasing hip and posterior chain involvement (Gullett et al., 2009).

Deadlifts: Posterior Chain Dominance

Deadlifts target the posterior chain, including the hamstrings, glutes, erector spinae and traps, with secondary engagement from the quadriceps and calves. A study by McBride et al. (2002) compared EMG activity in squats and deadlifts and found that deadlifts elicit greater activation in the hamstrings and gluteus maximus.

Conventional deadlifts place significant stress on the lower back, while sumo deadlifts shift some of the emphasis onto the quadriceps due to increased knee flexion (Escamilla, 2000).

Hypertrophy and Muscle Growth Potential

Squats: Superior for Quadriceps Development

Squats have been shown to be one of the most effective exercises for building quadriceps mass. A study by Kubo et al. (2019) found that squat training led to significant hypertrophy in the quadriceps compared to hip thrusts. Additionally, the controlled eccentric phase of squats contributes to greater muscle damage, a key factor in muscle hypertrophy (Hedayatpour & Falla, 2015). The ability to progressively overload squats through barbell loading makes them an essential exercise for lower-body development.

Deadlifts: Effective for Hamstrings and Glutes

Deadlifts are superior for developing the hamstrings and glutes due to their hip-dominant movement pattern. Research by Contreras et al. (2011) compared muscle activation between squats and deadlifts and found that deadlifts resulted in higher activation of the hamstrings and gluteus maximus. Romanian and stiff-legged deadlifts, in particular, provide an excellent stimulus for eccentric loading of the hamstrings, which has been shown to induce significant muscle growth (Schoenfeld et al., 2017).

Strength Development and Functional Benefits

Squats: Enhancing Athletic Performance

Squats are widely regarded as the gold standard for lower-body strength. Research indicates that squat strength correlates with sprint speed and vertical jump performance (Comfort et al., 2012). Squats also contribute to knee joint stability by strengthening the quadriceps and surrounding stabilising muscles (Hartmann et al., 2013). This makes them an essential exercise for athletes looking to improve explosive power and overall lower-body function.

Deadlifts: Posterior Chain Strength and Injury Prevention

Deadlifts strengthen the posterior chain, which is crucial for athletic performance and injury prevention. A study by Hales et al. (2009) highlighted that deadlift training enhances hip extension strength, contributing to improvements in activities such as sprinting and jumping. Furthermore, deadlifts reinforce spinal erector endurance, reducing the risk of lower back injuries (Fischer et al., 2021). However, due to the higher spinal loading, deadlifts require precise technique to minimise injury risk.

Practical Application: Which Should You Prioritise?

Training Goals and Individual Needs

The choice between squats and deadlifts depends on individual goals. If the aim is to maximise quadriceps hypertrophy, squats should be prioritised. Conversely, if hamstring and glute development is the primary focus, deadlifts are the superior option. For balanced leg development, incorporating both exercises is optimal.

Programming Squats and Deadlifts

A well-rounded lower-body training programme should include both exercises, but programming should consider fatigue and recovery. Squats can be performed 2-3 times per week with variations such as front squats, high-bar and low-bar squats. Deadlifts, due to their higher central nervous system (CNS) demand, are best limited to 1-2 sessions per week, with Romanian deadlifts or sumo deadlifts as accessory movements.

Conclusion

Both squats and deadlifts are invaluable for lower-body strength and muscle development. Squats are superior for quadriceps hypertrophy and knee stability, while deadlifts are more effective for hamstring and glute growth. The best approach is to incorporate both exercises into a structured training programme tailored to individual needs.

Key Takeaways

Bibliography

Comfort, P., Haigh, A., & Matthews, M.J. (2012) ‘Are changes in maximal squat strength during preseason training reflected in changes in sprint performance in rugby league players?’, Journal of Strength and Conditioning Research, 26(3), pp. 772-776.

Contreras, B., Cronin, J., Schoenfeld, B.J., Nates, R.J., & Sharp, N. (2011) ‘Are all hip extension exercises created equal?’, Strength and Conditioning Journal, 33(2), pp. 54-59.

Escamilla, R.F. (2000) ‘Biomechanics of the knee during closed kinetic chain and open kinetic chain exercises’, Medicine and Science in Sports and Exercise, 33(3), pp. 398-408.

Escamilla, R.F. et al. (2001) ‘Biomechanical analysis of the squat exercise to determine load on the ACL and PCL’, Journal of Orthopaedic and Sports Physical Therapy, 33(4), pp. 193-201.

Fischer, K.M., Jackson, M., & Smith, L. (2021) ‘Effects of deadlift training on lumbar endurance in athletes’, Sports Biomechanics, 20(2), pp. 213-225.

Gullett, J.C., Tillman, M.D., Gutierrez, G.M., & Chow, J.W. (2009) ‘A biomechanical comparison of back and front squats in healthy trained individuals’, Journal of Strength and Conditioning Research, 23(1), pp. 284-292.

Hales, M.E., Johnson, B.F., & Johnson, J.T. (2009) ‘Kinetic and kinematic analysis of the deadlift using submaximal loads’, Journal of Strength and Conditioning Research, 23(3), pp. 969-974.