The BEST Hamstring Exercises For Strength & Size - Science of Training

Summary

This video breaks down the science of hamstring training, explaining their anatomy, biomechanics, and optimal exercises for growth. It highlights the differences between medial and lateral hamstrings, their role in knee flexion and hip extension, and how muscle length affects activation. Squats are shown to be ineffective due to simultaneous hip and knee movement, while exercises at long muscle lengths, like seated leg curls and Romanian deadlifts, maximize hypertrophy. The video also provides practical tips for targeting specific hamstring regions, adjusting foot rotation, and selecting exercises based on equipment availability, ensuring effective and balanced hamstring development for strength, performance, and aesthetics.

Takeaways

• 💪 The hamstrings consist of four muscles: semimembranosus, semitendinosus, biceps femoris long head, and biceps femoris short head, which have distinct origins, insertions, and functions.
• 🦵 Medial hamstrings (semimembranosus and semitendinosus) can internally rotate the hip and lower leg, while lateral hamstrings (biceps femoris) can externally rotate them.
• 🔄 Hamstring activation varies with foot rotation: toes out emphasizes biceps femoris, toes in emphasizes semimembranosus and semitendinosus.
• 📈 Proximal hamstring regions are more activated by hip extension exercises, while distal regions are more activated by knee flexion exercises, especially at higher contraction speeds.
• ⚖️ The hamstrings operate optimally at longer muscle lengths; stretching them during hip flexion and knee extension maximizes force and hypertrophy.
• ❌ Squats are ineffective for hamstring growth because simultaneous hip and knee extension limits hamstring tension.
• 🏋️ For knee flexion exercises, using a hip-flexed position (e.g., seated leg curl, glute-ham raise, or band/cable curls) enhances hamstring activation.
• 🦿 For hip extension exercises, keeping the knees extended or nearly extended (e.g., Romanian deadlifts, stiff-legged deadlifts, good mornings, hip bridges) targets hamstrings effectively.
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• 🎯 Foot and hip positioning can be adjusted to emphasize medial or lateral hamstrings based on individual needs or sport-specific goals.
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• ✅ The best overall strategy is to include both knee flexion and hip extension exercises performed at long hamstring lengths, with progressive loading over time.
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• 🏆 If selecting a single exercise, seated leg curls with toes forward are recommended for stable, long-length hamstring activation hitting both medial and lateral heads.

Q & A

What are the main muscles that make up the hamstrings?

The hamstrings are composed of three muscles: the semimembranosus, semitendinosus (both medial), and the biceps femoris, which has a long head (lateral) and a short head (lateral).

Why are squats generally ineffective for hamstring hypertrophy?

Squats involve simultaneous hip and knee flexion and extension, which prevents the hamstrings from producing significant force and limits tension, reducing hypertrophy.

How does the hamstring’s length change with hip and knee movement?

Hamstrings lengthen when the knee extends or the hip flexes, and they shorten when the knee flexes or the hip extends.

What is the functional difference between the medial and lateral hamstrings?

Medial hamstrings (semitendinosus, semimembranosus) can internally rotate the hip and lower leg, while lateral hamstrings (biceps femoris) can externally rotate them. Both flex the knee and extend the hip, except the biceps femoris short head, which does not cross the hip.

How can foot rotation affect hamstring activation during leg curls?

Rotating the foot outward increases activation of the biceps femoris, whereas rotating the foot inward emphasizes the semimembranosus and semitendinosus.

What is the significance of working hamstrings at a long muscle length?

Exercises performed at a long hamstring length produce greater overall activation and hypertrophy compared to exercises at a short muscle length.

Which exercises target knee flexion with the hip flexed?

Seated leg curls, glute-ham raises with the hip flexed, razor curls on the ground, and band or cable leg curls performed with hip flexion are effective options.

Which exercises are recommended for hip extension with the knee extended?

Back extensions (GHD or Roman chair), long lever bridges, Romanian deadlifts, stiff-legged deadlifts, and good mornings are recommended, focusing on keeping the knee extended and hinging at the hips.

How do proximal and distal regions of the hamstrings respond to different exercises?

Proximal regions are more stimulated by hip extension exercises, while distal regions respond better to knee flexion and high-speed contractions.

What is the practical approach for designing a hamstring training program?

Include both knee flexion and hip extension exercises, prioritize movements performed at a long muscle length, experiment with foot rotation for medial/lateral emphasis, and choose exercises based on available equipment and personal goals.

Why does the biceps femoris short head not respond to hip-length adjustments?

Because the biceps femoris short head does not cross the hip joint, changes in hip position do not affect its length or activation.

What common mistakes reduce hamstring exercise effectiveness?

Common mistakes include choosing ineffective exercises, performing movements at the wrong hip or knee angle, and failing to maintain proper form, such as letting the butt rise during curls.