Effects of surface inclination on Gastrocnemius, Soleus and Tibialis Anterior muscle activation during gait

Abstract

Inclined walking is associated with multiple musculoskeletal benefits due to which it is considered as a therapeutic exercise. Various patterns of increased and decreased muscle activation with inclined surfaces have been observed in normal muscles, with an intent to implement those changes for the training of patients with neurological gait pathologies (parkinson’s gait, myopathic gait, hemiplegic gait) as well as in sports training. The aim of this study was to assess electromyographic activation of Gastrocnemius, Soleus, and Tibialis anterior at various inclined surfaces during gait, in order to implement those changes in gait training of patients with neurological pathologies and for designing protocols. Fourteen healthy male participants from age 17-30 walked at a self-selected speed at motor driven treadmill on 0, 2 and 4 degrees of inclination. EMG activity of the muscles was recorded using Delsys Trigno surface EMG system. Results showed that muscular activation (root mean square) value of Tibialis anterior significantly decreased with increase in the level of inclination (p= 0.011). Median and Interquartile ranges were 3.7x10-5 (1.17x10-4), 3.1x10-5 (2.2 x 10-5), 3.0x10-5 (2.8x10-4) at 0, 2 and 4 degrees of inclination. However, Soleus, Gastrocnemius medialis and Gastrocnemius lateralis showed no significant differences (p= 0.751, p= 0.56, p= 0.510) in their muscular activation, and no noticeable trends were found. These differences in activation patterns found in distal extremity can be useful for designing rehabilitation protocols for patients with neurological and musculoskeletal pathologies.