A non-Invasive Assessment of Ground Reaction Forces in the Human Leg in Response to Walking, Jogging, Running and Jumping

Abstract

Running is one of the most popular forms of exercise. Even though regular exercise is beneficial to human health, running is also often associated with an increased risk of injury. Lack of shock absorption in running shoes has often been stated as one of the main reasons for why running-related injuries have been on the increase. The aim of the present study was to assess the degree to which ground reaction forces (GRF) can be dissipated in the human leg in a barefoot subject, in connection with diverse physical activities. Acoustic myography (AMG), a non-invasive technique that records pressure waves from contracting muscles as well as the harmonic damping of ligaments, was applied to four anatomical sites on the subject's leg, during barefoot walking, jogging, running and jumping. The data for walking on a hard surface show much lower ESTi TM parameters than those for the soft surface, and these lower values are observed mainly for sites 1 (toes; 65%) and 2 (ankle; 53%), respectively. AMG parameters for jogging reveal this gait to have very low ES-Ti TM parameters for site 1 and site 2 (ESTi 2-3), yet similar for both surfaces. The data for running on a hard and soft surface revealed much lower ESTi TM parameters (38%) than those for sites 3 (knee) and 4 (hip). The data from the big jump, reveal that on a hard surface, the lowest ESTi TM parameters were for sites 1 (toes; 46%) and 2 (ankle; 27%), compared to values on a soft surface. The speed with which GRFs were transmitted up the leg varied from site to site and also with the type of activity, ranging from undetectable to approx. 60 m/sec. The present study reveals that the ankle joint is exposed to the greatest forces during jumping and running. In addition, this study has confirmed that exercising on a hard surface does indeed increase the stress forces on the toes and ankles. It is interesting to note that the data reveal that toes and ankles absorb most of the GRF during running, while the knee and hip How to cite this paper:

Acoustic Myography: Its Assessment of Ground Reaction Forces as Measured through Forelimb and Hind Limb of the Horse during Mild Exercise

“…As a technique, AMG enables a detailed and accurate measurement of active tissues, particularly those involved in movement, is independent of electrical signals measuring pressure waves solely, is portable, easy to use, inexpensive, re-useable and non-invasive [12]. Furthermore, it should be mentioned that this technique was used recently to measure the suitability of acoustic myography as a technique for assessing how ground reaction forces are dealt with in key sites up the human lower limb [13]. The main aim of this study was to measure the dampening of GRF in the forelimb bones of the horse with the hypothesis being that a measured GRF signal dissipates rapidly as it travels up a healthy equine limb.…”