Compression Socks

Bio-Physio Sport Sock Concept

By: Ray Fredericksen
Submitted to: Dr. Graham Kelly
June 9, 1995

Description: A sport sock design that incorporates a compression principle to enhance physiological metabolism, and biomechanical support panels to assist the natural biomechanisms of the lower extremity, to improve performance during athletic activity.

It is estimated that over 50% of the adult population will experience a venous blood flow disorder during the natural process of aging. Such disorders range from mild leg pain and discomfort to more serious venous disorders such as phlebitis and ulceration’s complicated by diabetes. This is most significant in light of the fact that the U.S. population is shifting to an age of over fifty years, when the effects of venous disorder are most noticeable. These disorders can be attributed to a breakdown of the elastic qualities of the body’s connective tissue, which normally occurs with aging.

Elastic compression hosiery has been a successful treatment modality for various venous return disorders. The elastic nature of the compression sock aids the natural venous return, “muscle pump,” mechanisms of the lower leg; i.e. gastrocnemius and soleus muscles. The increased venous return has been associated with pain relief enhanced blood circulation and metabolism, and general improvement in health.

For the healthy, elite athlete, as well as the active older individual, the benefits of a compression physiologic sock may offer potential performance benefits and preventive injury modalities.

The Bio-Physio sock incorporates many of the same qualities of the therapeutic compression sock. As the population ages, but continues to maintain an active healthy lifestyle, the Bio-Physio sock has application as a preventive medicine modality. The physiological benefits are improved blood circulation in the lower extremity and an associated enhancement of metabolic rate during exercise.

Incorporated into the Bio-Physio sock design, are special biomechanical support panels. These panels are specifically arranged to support the musculo-tendon anatomy of the foot and lower leg. They function to support and stabilize the intricate architecture of the lower leg and foot. Thirty three muscles originate in the lower leg and foot.

They provide a complex series of interactions with the skeletal structure to move and manipulate the foot and leg during human movement.

Typically, during human walking, an individual will contact the ground with his/her foot with a vertical ground reaction force of 1.25% times body weight. In more dynamic activities such as running or jumping, an individual may experience vertical forces of three times to five times body weight respectively.

The natural shock attenuating mechanism of the body involves a complex series of joint motion of the lower extremity and foot, defined as pronation. The muscles which originate in the lower leg insert into the tarsal bones to support the arches of the foot. These muscles function as a series of pulleys to relax, facilitate, and stabilize, the foot during the contact phase of human gait.

Immediately after foot contact with the ground, a reflex action of the body turns the foot and ankle joint complexes from a rigid to mobile position in order to attenuate impact shock. Anterior lower leg muscles such as tibialis anterior, and flexor extensor longus, contract in order to slow down the rate of foot contact with the ground. Posterior muscle groups; tibialis posterior, and gastrocnemieus, relax and twist inward as the arches of the foot flatten during pronation. Peroneal muscle groups work synergistically to provide stability of the foot from contact through propulsion. This sequence of motion allows the joint complexes of the foot to flatten and pronate in order to attenuate the forces associated with ground impact. After midstance, this sequence of joint motion and muscle activity reverses and is defined as supination. This interaction of motion and muscle activity puts the foot back into a rigid position for efficient push off during propulsion.

Pronation and supination are normal sequences of the foot and ankle joints by which the body attenuates impact shock, stores energy, and propels itself forward during normal human motion. Excessive motion however, has been associated with over use musculo-skelatal injury. Excessive motion fatigues muscles and stresses tendons and bones to the point where tendonitis and stress fractures may occur. This is especially important in highly repetitive activities such as running, walking, and aerobic dance.

The Bio-Physio sport sock design incorporates anatomical support panels to provide stability to muscles of the lower leg and joint complexes of the foot and ankle.

The combination of physiologic compression and biomechanical support work synergistically in a sport sock design to enhance exercise metabolism and gait efficiency during athletic activity. The proposed Bio-Physio design has application for athletic apparel designs, from casual sport socks, and athletic tights, to technical supportive modalities.

MSU independently concluded that VO2 max. was increased up to 2 1/2%. Penn State published many conclusive studies on the benefits of graduated compression socks.