Not only do our joints need to be mobile enough for movement to progress successfully, but we also need to be strong enough to control the forces that are acting on our body.
Gravity is a constant companion to our movement in this world- we work using the strength of our muscles to help move against it, and control it.
Walking as we looked at in our first week, is a series of double and single leg stance positions. Running differs, as it is essentially periods of flight, and periods of single leg stance. In addition to strength, walking also requires amazing timing- muscles sequencing in harmony to assist us with the incredible orchestration of smooth gait. The strength and mobility are much easier goals to achieve- working with timing usually requires the assistance of a trained PT and usually some form of electrical stimulation.
Dr. Perry and her team studied gait using force plates, joint markers to measure mobility at segments, and indwelling or surface electrodes to measure EMG (electromyography)- a tool that gives information about the amplitude of activation within a given muscle.
The highest forces to overcome (and therefore the highest muscular demand) in our walking cycle occurs at our ankle right at the transition between Terminal Stance (TSt) and Pre Swing (PSw). Recall, these phases are also the times when the most big toe and ankle mobility are required.
During this period of our gait cycle, most of the muscles of the lower limb (the gastrocnemius/soleus, tibialis posterior, fib