The Effects of Slow Eccentric Tempo During Squats On Quad Strength and Muscle Growth
Can you go slow and grow?
The study "The effects of eccentric phase tempo in squats on hypertrophy, strength, and contractile properties of the quadriceps femoris muscle" by Kojic et al. (2025) looked into the impact of eccentric tempo on muscle adaptations.
Key Points
Aim
The researchers aimed to investigate how the speed of the lowering (eccentric) phase in squats affects muscle growth, strength gains, and muscle properties in the quadriceps. They compared a fast eccentric (FE) tempo (1 second down) to a slow eccentric (SE) tempo (4 seconds down) over a 7-week training period.
Methods
18 participants (10 males, 8 females, average age 24) with no recent resistance training experience
Two groups: Fast Eccentric (FE) and Slow Eccentric (SE)
7-week squat training program, 2 sessions per week
FE group: 1 second down, 1 second up
SE group: 4 seconds down, 1 second up
Both groups used 60-70% of their one-rep max (1RM) for 3-4 sets with 2-minute rest periods
Measurements: Quadriceps size (CSA), squat strength (1RM), and muscle contractile properties
Results
Strength Gains: Both groups improved, but the SE group had significantly greater increases in 1RM strength.
Muscle Growth: All quadriceps muscles grew, but the SE group showed significantly more growth in the vastus lateralis (outer thigh muscle).
Muscle Properties: Both groups showed decreased muscle displacement in the rectus femoris, indicating increased muscle stiffness. The SE group also had a significant increase in contraction time.
Related
Practical Application
This study offers some interesting insights for those looking to optimise their squat workouts:
Slower is Better for Growth: If your goal is to build bigger quads, especially the outer thigh muscle, consider slowing down the lowering phase of your squats. Aim for about 4 seconds on the way down.
Strength Gains: While fast and slow tempos improved strength, the slower tempo led to slightly better strength gains. This suggests that incorporating slower eccentric movements periodically can be beneficial.
Muscle Stiffness: Both tempos increased muscle stiffness, which is generally associated with improved force production. This means that regardless of the tempo, consistent squat training can lead to positive adaptations in muscle function.
Time Efficiency: If you're short on time, know that even faster tempos still produce significant benefits. You don't always have to go slow to see results.
Variety is Key: Consider incorporating both fast and slow tempos into your training routine. This can help target different aspects of muscle adaptation and keep your workouts engaging.
Key Takeaways
Slower eccentric (lowering) tempos in squats may lead to greater muscle growth, particularly in the outer thigh.
Both fast and slow tempos improve strength, with a slight edge to slower tempos.
Consistent squat training, regardless of tempo, increases muscle stiffness, which is beneficial for force production.
The study highlights the importance of tempo as a variable in resistance training, particularly for lower-body exercises.
These findings suggest that manipulating eccentric tempo can be an effective strategy for tailoring workouts to specific goals, whether that's maximising muscle growth or strength gains
Reference
Kojic, F., Mandic, D., & Duric, S. (2025). The effects of eccentric phase tempo in squats on hypertrophy, strength, and contractile properties of the quadriceps femoris muscle. Frontiers in Physiology, 15, 1531926. https://doi.org/10.3389/fphys.2024.1531926