The Science of Hamstring Flexibility
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Do you struggle to touch your toes? Have you been told it’s because your hamstrings are weak, not because they’re tight? If so, you’re being gaslit. While your hamstrings might be weak, when it comes to flexibility, you need to train these tissues with stretching exercises.
Tight hamstrings impact your posture, your walking and running gait, and can even contribute to lower back problems. Since your hamstrings are involved in nearly all your movement patterns (think knee flexion and hip extension) if left unchecked, the progressive tightening of these tissues is the norm—but it doesn’t have to be.
Your hamstring range-of-motion is determined by two factors: your nervous system and the length of your tissues. The Science of Stretching is a targeted approach I’ve developed that combines exercise physiology research with best practices from yoga, gymnastics, and dance. It’s really effective at unlocking any muscle in your body, but here we’ll focus on your hamstrings.
Hamstrings Anatomy
The hamstrings are a group of three muscles located at the back of your thigh: your biceps femoris, semitendinosus, and semimembranosus. These muscles originate from the lower part of your pelvis and attach to the bones in your lower leg.
They are biarticular muscles, meaning they cross two joints (hip and knee), so they play a crucial role in coordinating movements when running and jumping. When your hamstrings become tight, they reduce flexibility and range of motion, which can lead to discomfort in your legs and lower back.
Science of Stretching Key Principles
The Science of Stretching is a targeted approach which is best understood through the following three principles:
Wet noodle. Muscles stretch best when completely relaxed. When you train for flexibility, try to relax into the poses as much as possible.
Breathe to relax (4:8 Breathing). Low breathing, where you double the length of the exhale, promotes a parasympathetic nervous system response, and dampens your body’s natural myotatic stretch reflex. You feel calm and relaxed, and your body doesn’t fight you in the stretch. To practice, inhale through your nose to the count of 1-2-3-4, and exhale through your mouth with a “ha” sound to the count of 8-7-6-5-4-3-2-1.
Time under passive tension. The gating factor for flexibility is time – how long you spend in these deep poses to create real change in your muscles. Typical Science of Stretching hold times are 2-5 minutes. Your body will always trend toward inertia, so the stopwatch is a way to measure, match, and eventually exceed your previous results.
Massage And Foam Rolling
Foam rolling does not improve your hamstring flexibility, but it can help with circulation and to relieve nervous system tension prior to deep stretching. If you enjoy foam rolling or any other form of self-massage, you can use it as a short prep before stretching.
Ragdoll Pose
This simple pose, when combined with Science of Stretching principles, will target change in the muscle fibers in your hamstrings.
- Stand behind a stool, chair, or coffee table, feet a little wider than your hips
- Soften your knees and hinge forward at your hips
- Place your forearms on the stool/chair in front of you for support
- Drop your head and relax as much as you can here
- Breathe in through your nose for 1-2-3-4, out through your mouth with a “ha” sound for 8-7-6-5-4-3-2-1
- Stretch at a 7/10 level of perceived intensity, holding the pose for between 2-5 minutes
Safety Disclaimer
This article is for educational purposes only. If you’re new to this this type of deep, passive stretching, remember to start slowly and ease your way into it. If you have severe hamstring pain or an injury, please err on the side of caution and check with a healthcare provider before practicing any self-care routine.
Want to Learn More?
- Science of Stretching 4-week program
- Check out our YouTube Channel (free to subscribe)
- The Lucas Rockwood Show Podcast
