When a person is in motion, it creates a chain of events that affects the movement of neighboring joints and segments.
The kinetic chain is a term used to describe the way a human body moves. It is especially relevant in physical therapy, sports medicine, neurorehabilitation, prosthetics, orthotics, and other areas of medicine that focus on the musculoskeletal system.
The basic concept is: the hip bone is connected to the thigh bone, the thigh bone is connected to the knee bone, etc. When you move one of those bones, it creates some sort of movement or effect, big or small, on the adjacent, nearby, and sometimes even not-so-close bones (and the muscles and connective tissues that interact with them).
This happens as a chain reaction. Medicine borrowed the engineering term kinetic chain to describe this set of linked movements. The concept of the kinetic chain as applied to the human body was first introduced in 1955 by Dr. Arthru Steindler based on the theory of mechanical engineer Franz Reuleaux.
For a real-life example of the kinetic chain in action, let’s think about what happens when we walk:
- We take a step forward with the right leg.
- This causes the pelvis to rotate forward on the right side and backward on the left.
- Since the pelvis is part of the trunk, the trunk automatically moves forward as well.
- The spine rotates into the right leg and pelvis as they extend forward, allowing you to continue looking straight ahead as you walk and see where you’re going.
Each of these movements provokes another. Some of the reactions are automatic, like the second, while others are reflexive, like the fourth.
A kinetic chain can be described as upper or lower. Kinetic chain exercises are open or closed. The biggest advantage of open chain exercises is that they are much better at isolating a muscle. This can be helpful when rehabbing a specific muscle or when training for a sport that requires the use of open chain activities. An example is throwing a ball.
But closed chain exercises are more functional, or very close to the movements we would use in everyday life or in sports. This includes squatting to pick up furniture or bending over to pick up a child. Since the load is shared with other nearby muscles, closed-chain exercises may be preferable in recovery from some injuries.
Although some physical therapists and other professionals prefer to use one type of kinetic chain exercise over the other, research indicates that both have uses in pain management. There are open and closed chain exercises available for most muscle groups.
higher kinetic chain
The upper kinetic chain comprises:
- upper arms
- shoulder blades
- spinal column
lower kinetic chain
The lower kinetic chain is composed of:
- lower legs
- upper legs
open kinetic chain
A kinetic chain is considered “open” when the body part we are moving (typically a limb) is loose in space. In other words, the hand or foot can move freely and does not press against a surface. This allows a muscle or group of muscles to act in isolation.
Common examples of open exercises include:
- Bicep or leg curls
- chest press
- Raise your arms above your head while sitting on a chair
- Raise one leg while lying on your back
- shake a hand
- Extend the lower leg from the knee while sitting
Open kinetic chain exercises have several things in common. They are usually characterized by rotation at the primary joint, although rolling and other movements can also occur. Normally, only one segment moves at a time (for example, when extending the lower leg from the knee, the lower leg moves but the upper leg remains stationary). Also, only the muscles associated with a joint are involved.
Open kinetic chain exercises can be used to improve the strength and function of a muscle or isolated muscle group. This can be beneficial at the beginning of a rehabilitation program or when improving aesthetics, such as for a bodybuilder. However, closed kinetic chain exercises may be more beneficial in some circumstances.
closed kinetic chain
A kinetic chain is considered “closed” when the body part you’re using (again, usually an arm or leg) is pinned against a hard, unforgiving surface. When the body part is pressed against a wall or the ground, for example, the resistance returns to the trunk. The parts of the body through which the resistance moves make up the components of the chain for that particular movement or exercise.
Examples of closed kinetic chain exercises include:
- Cat-cow yoga stretch
- hip bridge
Characteristics of closed kinetic chain exercises are linear tension patterns, movement that occurs at multiple joints and multiple joint axes, simultaneous movement of more than one segment, and promotion of joint stabilization. As multiple segments are in motion, more muscles contract at the same time to stabilize and control movement at multiple joints.
Closed kinetic chain movements are typically used to strengthen core muscles and stabilize posture. One benefit of closed kinetic chain exercises is that the movements they promote are often more closely related to activities of daily living, so they are considered more “functional.”
Sometimes in rehab a person will use open chain exercises to strengthen an isolated area and then move on to closed chain exercises.