‘For every action, there is an equal and opposite reaction.’ - Isaac Newton
What is ground reaction force? According to the 3rd Law of Motion, each time your foot hits the ground while walking, standing or running, a ground force is produced.
This force can have a significant impact on the walking stride of a person, and measuring it can help in identifying walking problems. Understanding ground forces can help individuals, especially athletes, know more about balance and posture and how these are affected by external factors.
Understanding Ground Force
When a person stands motionless, they exert a contact force on the ground which is equal to their bodyweight. In the same manner, an equal but opposing ground force, is exerted back. This acts like a mirror of the force the person exerts on the ground.
This is the reason why ground force can be used to examine the force a person exerts. It can help identify and correct any problems in walking stride, running form, jumping technique and other movements that involve the feet. Measuring the ground force can be beneficial in designing active rehab programmes for athletes.
Foot Posture and Ground Force
When there is healthy distribution of force to the feet, the foot muscles are able to function properly with the least amount of work. However, with improper distribution of force, there is imbalance in the foot muscles. This can lead to abnormal movements of the feet which may affect the postural alignment of the lower body.
Improper distribution of force to the feet can be caused by a weak foot posture. With flat feet, the foot arch flattens on the ground, causing misalignment and imbalance in the foot. This causes the shin and thigh bones to twist inwards, stressing the ankles, knees and hips as a result. Poor stability and added stress on the lower body, increases the risk of injury and developing chronic conditions.
Ground force is often measured through a detailed examination of the foot, walking stride and overall body posture.
Use of Foot Orthotics
If left untreated, a weak foot posture may cause or contribute to the degeneration of the muscular and skeletal system. By measuring ground force, a health care professional is in a better position to recommend a personalised treatment programme.
MASS4D® foot insoles can be included as part of a supportive care or active rehab programme. MASS4D® supports the feet in their optimal posture which promotes postural alignment and encourages proper distribution of force to the feet.
By restoring healthy movement in the feet, MASS4D® insoles aim to promote stability and balance to reduce stress on the lower body and help prevent foot deformities or injuries.
Copyright 2018 MASS4D® All rights reserved.
Reference: Winiarski S., Rutkowska-Kucharska A. (2009) Estimated ground reaction force in normal and pathological gait. Acta of bioengineering and biomechanics: February 2009, Vol. 11, No. 1, pp. 53-60
Reference: Soutas-Little W. R. (1998) Gait Analysis in the Science of Rehabilitation. Chapter 2: Motion Analysis and Biomechanics. DIANE Publishing.
Like any other fast-paced sport, skiing carries a risk of injury which should be considered while preparing for ski season. Develop your own protective measures to remain injury-free on the slopes by learning about the risk factors responsible for some common lower body injuries in skiing.