Ales Dolenec

Comparison of lower leg muscle activity in running on tarmac and grass

The observation that dynamic ankle DF is not predicted by passive ankle DF is consistent with previous observations of low correlation between static and dynamic measures (Hamill et al. 1989). This highlights the importance of measuring ankle DF during dynamic running gait if seeking to identify those with limited functional ankle DF. Through measurement of dynamic ankle DF during running, it has been possible to identify those recruits will low functional DF. The additional measurement of plantar pressures has revealed that limited dynamic ankle DF does not necessarily lead to high MT3 loading. The low correlations between peak ankle DF in running and the magnitude of load, represented by peak force, loading rate or impulse, suggests that factors other than ankle DF are important in determining the load on this area. This finding is consistent with that of Sacco et al. (2001), investigating walking, and highlights the importance of measuring forefoot loading directly, rather than inferring load from kinematic measurements of DF.

Peroneal muscle activity during different types of walking

BackgroundAs the most common form of movement, walking happens not only on flat but also on uneven surfaces, where constant loss and regaining of balance occur. The main balancing function of the ankle joint is performed by tibial muscles. When changing inclination in a frontal plane, an essential balancing function is performed by the peroneal muscles. One of the methods for improving the activity of peroneal muscles is walking with different foot placement. The objective of this study was to analyze the activity of the peroneal muscles when performing different types of walking.MethodsSixteen healthy participants took part in this study, walking on a flat surface (NORM), on a medial incline ramp with the plantar surface of the foot fully placed on the surface (FULL), and on a medial incline ramp with elevated lateral part of the foot (LAT). We monitored the changes of EMG signals in peroneus longus (PL), peroneus brevis (PB), tibialis anterior (TA), soleus (SOL), gastrocnemius medialis (GM) and gastrocnemius lateralis (GL) muscles. We monitored kinematic parameters (gait speed, stride length, contact time, foot position). The parametric ANOVA test and a non-parametric Friedman test were used at an alpha level of 0.05.ResultsThis study shows that the EMG activities of peroneal muscles increases when walking on the medial incline ramp. Statistically significant EMG differences were observed in the peroneal muscles, TA and GL muscles. We observe a very high percentage of normalized EMG value of the PL muscle in LAT walking. Walking on a medial incline ramp impacts the foot position, contact time, and stride length but not the gait speed.ConclusionsWalking on a medial incline ramp could be an effective exercise to improve the neuro-muscular function of the peroneal muscles and, therefore, might be a suitable exercise for people with weakened ankle evertors.