Optimal Hamstring Activation: The Best Training Methods Revealed

Anterior Cruciate Ligament (ACL) injuries are a prevalent concern among athletes, with female athletes being particularly susceptible. A crucial aspect of mitigating this risk is the strength ratio between the quadriceps and hamstrings.

In this blog post, we delve into the significance of hamstring training, supported by insights from a comprehensive study conducted by the American Council on Exercise (ACE).

Understanding the ACE Study

The ACE study featured sixteen volunteers, evenly split between males and females, aged 20-25, all possessing prior resistance training experience. The study’s primary objective was to identify effective hamstring exercises that activate the biceps femoris (BF) and semitendinosus (ST), given the impracticality of accessing the semimembranosus muscle. Participants engaged in two sessions to establish a baseline of their one-repetition maximum (1-RM) weight, specifically 70% of it.

In the second session, subjects underwent maximum voluntary contractions and evaluated nine hamstring exercises randomly. Surface electrodes meticulously tracked BF and ST activation levels.

The study pinpointed that kettlebell swings and single-arm/single-leg Romanian deadlifts elicited activation levels similar to those achieved with the prone leg curl machine.

Biceps Femoris Activation

Semitendinosus Activation

Images from acefitness.org

The Implications of Kettlebell Swings

kettlebell swing

While the ACE study endorses incorporating kettlebell swings into your training regimen for hamstring development, it is essential to recognize the ballistic nature of this exercise. Kettlebell swings demand an intricate blend of skills and athleticism, with three key factors that can potentially elevate the risk of injury:

  • Increased speed
  • Heavier weight loads
  • Depth of movement

One crucial consideration during kettlebell swings is the involvement of proprioceptors, such as muscle spindles, which become particularly active during high-speed movements. This heightened neuromuscular activity emphasizes the importance of maintaining proper form and technique to safeguard against injuries, particularly in the vulnerable lower back region.


In the pursuit of reducing the risk of ACL injuries, hamstring training is paramount, especially for female athletes who often exhibit a significant strength ratio disparity between their quadriceps and hamstrings. The ACE study highlights the effectiveness of exercises like kettlebell swings and single-arm/single-leg Romanian deadlifts in achieving optimal hamstring activation. However, it is essential to approach kettlebell swings with caution, considering their ballistic nature and the potential for increased injury risk.

For those seeking a safer alternative with comparable hamstring activation, the single-leg Romanian deadlift offers an appealing solution. Ultimately, maintaining a well-balanced and informed approach to hamstring training is key to athletic success and injury prevention.

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