Muscular Analysis of The Burpee
Phase 1: Squat Position
From standing position to squat position.
Squat down so the hands are flat on the ground. The knees and hips are flexing and the ankle is moving into dorsi flexion. The spine is also flexing to a minor degree. This movement requires the eccentric contraction of the quadriceps, hamstrings, and the gluteus maximus. The muscles of the back are working to prevent excessive flexion of the spine. Think about holding the chest high. Eccentric means that the muscles are contracting and lengthening at the same time. The muscles are producing force to control the rate of descent against the effects of gravity.
Phase 2: Push-up Position
From Squat position with the hands on the ground, to the start of the push-up position.
- From the squat position, using the arms to support the upper body, the legs are thrust back until the body is elongated into the start of the push-up position.
- This movement requires concentric contraction of the quadriceps to extend the knee, and concentric contraction of the hamstrings and gluteus maximus to extend the hip.
- The pectoralis major, anterior deltoid, and rotator cuff are contracting isometrically to stabilize the shoulder and the triceps brachii are contracting isometrically to stabilize the elbow. Isometric is a term to describe a muscular contraction without movement. In this case, the pectoralis major, anterior deltoid, and triceps brachii are producing just enough force to oppose the effects of gravity and prevent the chest from crashing to the ground.
- Muscles of the scapula, including the trapezius, rhomboids, serratus anterior, and the pectoralis minor, are contracting isometrically to stabilize the scapula. These muscles are co-contracting creating a stabilizing effect on the scapula so the muscles of the rotator cuff have a stable platform to act upon.
- Muscles of the trunk are contracting isometrically to stabilize the core and prevent unwanted movement in the spine. Muscles that extend and flex the spine are co-contracting to stabilize the spine. If you notice the back sagging or an exaggerated arch in the back this is indicative of a weakness in the abdominal muscles. Practice the Plank exercise to strengthen this region.
Phase Three: The Push-up
One push-up is completed.
- The chest is lowered to the ground in a controlled fashion. It should be fast but under control. The pectoralis major and anterior deltoid muscles contract eccentrically allowing the shoulders to horizontally abduct. The triceps brachii contracts eccentrically to allow the elbow flex.
- The torso should be rigid throughout the movement; the muscles of the trunk continue to act as stabilizers.
- In the down position, the pectoralis major, anterior deltoid, and triceps brachii contract concentrically causing shoulder horizontal adduction and elbow extension respectively, returning to the body back to the up position.
Phase Four: Return to Squat Position
From the top of the push-up position to the squat position
- This is an explosive movement where the athlete springs back to the squat position.
- The gastrocnemius, contracts forcefully causing plantar flexion, lifting the feet from the ground so that the knees and hips can be rapidly flexed and the body is returned to the squat position.
- Flexion of the hips is caused by a concentric contraction of the iliopsoas and rectus femoris muscles and flexion of the knee is caused by concentric contraction of the hamstring muscles.
Phase Five: Jump
From the squat position the athlete jumps as high as possible.
- Jumping is the product of a forceful concentric contraction of the gastrocnemius muscle at the ankle, the quadriceps at the knee, and gluteus maximus and hamstrings at the hip, causing plantar flexion, and knee and hip extension respectively.
- Prior to the jump the back should be rigid and this stabilization is provided by the back extensors.
Tags: WOD Fundamentals