Lifting your feet higher costs LESS energy when running

Summary

This video script addresses a common misconception in running technique: that lifting feet higher conserves energy. Using physics principles, it explains how a shorter lever (foot closer to the body) requires less energy. The script debunks this myth with 3D camera analysis, showing that relaxed running with a natural foot swing is more energy-efficient. It also touches on the importance of cadence and the biomechanics of running, concluding that the height of the foot and knee movement varies with pace and should be relaxed, not forced.

Takeaways

• 🚶‍♂️ Keeping feet close to the ground while running is a common mistake and can actually cost more energy.
• 🔍 The law of physics explains that a longer pendulum requires more energy to move than a shorter one.
• 🎭 In figure skating, bringing arms closer to the body increases spin speed, illustrating the energy efficiency of keeping limbs close to the center of mass.
• 🦿 Lifting the foot higher reduces the lever arm, making it easier and less energy-consuming compared to keeping the foot close to the ground.
• 🔄 The mechanical push of the tibia and the utilization of the stretch shortening cycle contribute to energy efficiency when running.
• 🏃‍♂️ Relaxation is key; the foot should not be actively lifted but should naturally swing up due to relaxation.
• 📏 The speaker's 3D camera measurements show that running with feet closer to the ground uses more energy than allowing the foot to swing up naturally.
• 📊 Despite a slightly higher cadence when feet are lifted, the energy cost of moving body parts is significantly lower.
• 🤔 Many recreational runners keep their feet too close to the ground, either due to muscle tension or a misconception about energy conservation.
• 🏃‍♀️ The height of the foot and knees during running should be adjusted based on pace, with faster runs allowing for bigger movements.
• 👟 The speaker emphasizes that personal preference plays a role in running style, but understanding biomechanics can help runners optimize their technique.

Q & A

Why does lifting feet and knees higher while running save energy?

Lifting feet and knees higher reduces the energy cost because it shortens the lever arm, which requires less force to move, similar to how a shorter pendulum moves faster than a longer one.

What is the role of relaxation in running technique?

Relaxation is key in running technique as it allows the foot to naturally swing up without active lifting, reducing energy expenditure.

How does the mechanical push of the tibia contribute to energy efficiency in running?

The mechanical push of the tibia contributes to better knee drive and a more efficient use of the stretch-shortening cycle, which helps save energy.

What is the 'rubber band effect' mentioned in the script?

The 'rubber band effect' refers to the energy saved from the stretch-shortening cycle, which is a phenomenon where the elastic properties of muscles help in conserving energy during movement.

How does the position of the foot relative to the center of mass affect running efficiency?

The foot moving closer to the center of mass reduces the lever arm, making it easier and less energy-consuming to move.

What does the script suggest about the relationship between cadence and energy cost in running?

The script indicates that even with a slightly higher cadence when the feet are lifted higher, the cost of moving body parts is significantly lower due to the reduced lever arm.

Why do some runners keep their feet too close to the ground?

Some runners keep their feet close to the ground because they believe it saves energy, or they are not good at relaxing, leading to resistance and higher energy cost.

How can the biomechanics of running be improved through relaxation?

By relaxing and allowing movements to happen naturally without forcing them, runners can improve their biomechanics and reduce energy expenditure.

What role does the core play in efficient running according to the script?

The core plays a significant role in efficient running by aiding in the movement of the hips and allowing for a more relaxed and natural running motion.

How does the height of the foot and knees during running relate to running pace?

The faster the pace, the bigger the movement of the foot and knees should be. It's important to adjust the height of the foot and knees according to the speed of running.

What does the script suggest about personal preference in running technique?

The script acknowledges personal preference in running technique, stating that if a runner prefers to keep their feet close to the ground, they should do so, as long as it's done with proper biomechanics.