Key Points of Squats vs Leg Extension Article
- The study compares squats vs. leg extensions’ effects on the quadriceps muscle.
- Although both exercises increased quad growth, leg extensions resulted in greater overall quad growth.
- Leg extensions resulted in greater quad gains for the vastus intermedius, vastus lateralis, and vastus medialis, while squats resulted in more muscle growth of the rectus femoris.
- Consider combining squats and leg extensions in your workout routine for the best quad gains.
Quad Growth Exercises
Resistance training is the bedrock of muscle growth and strength enhancement. Squats, a staple in the fitness world, are heralded as the “King of Quad Growing Exercises” for building mass in the quads. For those of you old enough, Tom Platz, who had some of the greatest quads in history, was an avid squatter. However, relying solely on squats may not fully unlock the growth potential of your quadriceps. A recent study analyzed muscle growth in the quads when doing both leg extensions and squats. This article explains the reasons behind this and highlights the importance of including leg extensions and squats in your workout routine for ultimate quad development.
The Anatomy of the Quadriceps
Squats primarily activate the quadriceps femoris muscles, a group of four muscles located in the front of the thigh. These muscles include the vastus lateralis, vastus medialis, vastus intermedius, and rectus femoris. The quadriceps are responsible for extending the knee joint during the squat movement.
The Science Behind Quad Growth: Squats vs Leg Extensions
Though primarily targeting the quadriceps, squats may not stimulate all quad muscles uniformly. Studies reveal that while parallel squats promote growth in all quadriceps muscles, strength gains are predominantly associated with the hypertrophy (increase in size) of the vastus lateralis (The outer part of the thigh) muscle. This implies that squats alone may not fully harness the growth potential of other quad muscles like the rectus femoris, vastus medialis, and vastus intermedius.(Behm et al., 2003; Zabaleta-Korta et al., 2021)
What Research Says About Squats and Quad Growth
Another factor to consider is the range of motion and joint angles involved in each exercise. Leg extensions primarily target the quadriceps muscles, where the feet are fixed, and the movement occurs at the knee joint. Conversely, squats involve a larger range of motion and multiple joints, including the knees, hips, and ankles. The greater range of motion and involvement of multiple joints in squats may lead to greater muscle activation and recruitment of more muscle fibers, resulting in greater quad growth compared to leg extensions.(Sjöberg et al., 2021)
Additionally, the exercises’ load and intensity can impact quad growth. Squats are typically performed with heavier loads than leg extensions, as they involve barbells or other forms of resistance. Squats’ higher load and intensity can stimulate greater muscle growth than leg extensions, often performed with lighter loads (Sjöberg et al., 2021).
What Research Says About Squats vs Leg Extensions and Quad Growth
Incorporating leg extensions into your workout routine can bridge this gap. As an isolation exercise, leg extensions primarily target the quad muscles, promoting a more balanced development. By integrating leg extensions into your training, you can specifically stimulate the rectus femoris, which may not be optimally activated by squats alone.
Muscle growth does not occur uniformly (i.e., evenly) throughout the muscle. Regional muscle growth refers to the phenomenon where different regions of a muscle grow in response to specific exercises that place the greatest difficulty in certain points of the range of motion (ROM) (Zabaleta-Korta et al., 2021) The regional hypertrophy reported in studies can be attributed to exercise selection and the resistance differences that the involved joints have to overcome (Zabaleta-Korta et al., 2022). The region of the RoM where the highest strain is placed is where athletes become strongest (Zabaleta-Korta et al., 2022).
A study compared the effects of squats in the Smith machine (and leg extension exercises (LEG group) on regional hypertrophy of the RF and VL muscles (Zabaleta-Korta et al., 2021). The results showed that the leg extension group experienced significant growth in the rectus femoris, while only vastus lateralis grew significantly in the Smith machine group (Zabaleta-Korta et al., 2021). This suggests that leg extensions specifically target the rectus femoris and can lead to regional hypertrophy in this muscle and better quad growth.
New Study on the Influence of Squats vs. Leg Extension Exercises on Quad Growth
A recent study titled “Differing hypertrophy patterns from open and closed kinetic chain training affect quadriceps femoris center of mass and moment of inertia” sheds light on this subject. The study compared leg extension vs. squats and its effects on muscle growth after 8 weeks of strength training. The training programs and RPEs were identical, and both groups standardized the range of motion (ROM) to a 90° knee angle depth.
The research reveals that while both squats and leg extension exercises led to similar increases in muscle growth, the regions of hypertrophy varied significantly. They found that squats resulted in more muscle growth in the upper part of the thigh (i.e., rectus femoris), while leg extensions resulted in more muscle growth in the lower part of the thigh (i.e., vastus lateralis). Interestingly, leg extensions were slightly superior to squats for overall quadriceps growth. (Earp et al., 2023) See the results below:
Implications for Outer Quad Exercises, Training, and Performance:
These findings have profound implications for training routines and athletic performance. Squats lead to more muscle growth in the upper thigh, but leg extensions result in more muscle growth in the lower thigh. Squats may be more beneficial for activities like running. Including a combination of leg extensions and squats in a well-rounded training program is often helpful in targeting different muscle groups and achieving optimal results.
Practical Implications for Quad Growing Exercises like Squats and Leg Extensions:
In conclusion, squats are invaluable for lower body development but may not yield optimal quad hypertrophy when performed alone. By integrating leg extensions into training programs, individuals can achieve more comprehensive and balanced quad development, leading to optimal muscle hypertrophy and strength gains. As research in this field continues, we can anticipate more insights that will help us train smarter and perform better.
References
Behm, D. G., Power, K., & Drinkwater, E. J. (2003). Muscle Activation Is Enhanced With Multi- And Uni-Articular Bilateral Versus Unilateral Contractions. Canadian Journal of Applied Physiology. https://doi.org/10.1139/h03-004
Earp, J. E., Angelino, D., Hatfield, D. L., Colantuono, V., Jackson, E. R., Morgan, K. D., Adami, A., Melanson, K. J., & Blazevich, A. J. (2023). Differing hypertrophy patterns from open and closed kinetic chain training affect the quadriceps femoris center of mass and moment of inertia [Original Research]. Frontiers in Physiology, 14. https://doi.org/10.3389/fphys.2023.1074705
Sjöberg, M., Berg, H. E., Norrbrand, L., Andersen, M. A. E., Gutierrez-Farewik, E. M., Sundblad, P., & Eiken, O. (2021). Comparison of Joint and Muscle Biomechanics in Maximal Flywheel Squat and Leg Press. Frontiers in Sports and Active Living. https://doi.org/10.3389/fspor.2021.686335
Zabaleta-Korta, A., Fernández-Peña, E., Torres-Unda, J., Francés, M., Zubillaga, A., & Santos-Concejero, J. (2022). Regional Hypertrophy: The Role of Exercise Resistance Profile in Trained Women. https://doi.org/10.21203/rs.3.rs-1530884/v1
Zabaleta-Korta, A., Fernández-Peña, E., Torres-Unda, J., Garbisu-Hualde, A., & Santos-Concejero, J. (2021). The Role of Exercise Selection in Regional Muscle Hypertrophy: A Randomized Controlled Trial. Journal of Sports Sciences. https://doi.org/10.1080/02640414.2021.1929736
How often should one integrate both squats and leg extensions for optimal quad growth?
To achieve optimal quad growth, the frequency of integrating squats and leg extensions depends on individual factors like fitness level and goals. Generally, performing both exercises 1-2 times per week is recommended. However, listening to your body and avoiding overtraining or injury is essential. Consulting with a personal trainer or fitness professional can provide personalized recommendations for your quad growth journey.
Additional Information
When it comes to building muscle in your lower body, two exercises reign supreme: leg extensions (LE) and squats (S). These exercises are the cornerstone of any effective leg workout, targeting your quads, hamstrings, and glutes. But how do you perform these exercises correctly, and how can you incorporate them into your routine for bigger quads? Let’s dive in.
Leg Extensions: A Key Quad Exercise
LE are an isolation exercise that specifically targets your quadriceps. To perform an LE, you’ll need a LE machine. Sit on the machine with your back against the pad and place your shins under the padded lever. Extend your legs until they’re straight, hold for a second, then slowly lower the weight back to the starting position. This is one rep.
LE are a great way to isolate your quads, but they should be part of a balanced leg workout that also includes compound exercises. Remember, nutrition is also key for muscle growth, so make sure you’re eating a balanced diet to fuel your workouts and recovery.
Squats: The Best Exercise for Lower Body Strength
S are a compound exercise that works your entire lower body. They target your quads, but also engage your glutes, hamstrings, and core. There are several variations of S, including the back squat, front squat, and goblet squat.
The back squat is performed with a barbell across your upper body, resting on your lower back. Keep your torso upright, push your pelvis back, and bend your knees to lower your body. Push back up to the starting position to complete one rep.
The front squat is similar, but the barbell is held at your chest in front of your body. This variation puts less strain on your lower back and more emphasis on your quads and core.
The goblet squat is performed with a kettlebell or dumbbell held at your chest. This variation is great for beginners or those with limited mobility.
Bulgarian split squats and hack squats are other effective quad exercises. The Bulgarian split squat is a single-leg exercise where the back foot is elevated, and the front foot remains on the ground. The hack squat, performed on a squat machine, allows you to lift heavy weights in a controlled manner, targeting the quads.
Lunges are another great exercise for your quads. They can be performed with bodyweight, dumbbells, or a barbell. They also improve your coordination and balance.
Sissy squats are a more advanced quad exercise that requires good balance and knee health. They target the quads by keeping the body upright and bending the knees to lower the body.
Compound movements like squats and lunges not only build stronger quads but also improve your overall lower body strength and core strength. They’re the best quad exercises for building muscle and improving endurance.
Leg Day: Putting It All Together
A balanced leg day might include a mix of these exercises. Start with a heavy weight compound exercise like back squats or front squats, then move on to lunges or Bulgarian split squats. Finish with isolation exercises like leg extensions or sissy squats. Remember, good form is crucial in all these exercises to prevent injury and ensure you’re effectively targeting your muscles. If you’re new to these exercises, consider working with a trainer to learn proper form.
Conclusion
Whether it’s leg day or you’re looking for the best exercise to build big quads, incorporating a mix of leg extensions and squats into your routine can lead to significant gains. Don’t forget the importance of nutrition in muscle growth and recovery. With the right approach, you’ll be on your way to stronger quads and improved lower body strength in no time.
What is the difference between squats and leg extensions?
Squats and leg extensions are both exercises that target the quadriceps muscles, but they do so in different ways. Squats are a compound exercise that engage multiple muscle groups, including the quads, while leg extensions isolate and specifically target the quads.
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