Ankle rehabilitation exercises often involve a progression of exercises that gradually increase the challenges to balance and proprioception. Therapists will progress patients from standing on stable surfaces to standing on unstable surfaces, or move from 2-leg standing to 1-leg standing in an effort to progress the intensity of an ankle exercise. Despite this common practice, few studies have quantified the EMG activity of ankle muscles during common balance exercise progressions.
Researchers in Spain had 44 healthy subjects perform 12 exercises in a random order while surface EMG was measured for 3 ankle muscles: tibialis anterior (TA), soleus (SOL), and peroneus longus (PL). Their results were published ahead of print in the journal, Gait & Posture.
The exercises included a TheraBand Exercise Station with tubing resistance, exercise ball, rocker board, and blue Stability Trainer. In general, bilateral exercises had the lowest activation, followed by unilateral stance exercises, and then unilateral stance with TheraBand tubing. The unilateral stance on Stability Trainer with tubing had the highest EMG levels in all 3 muscles. The researchers found that the rocker board and blue Stability Trainer ha similar levels of activation. Interestingly, adding bilateral front raise exercise with elastic resistance in 1-leg stance did not increase activation of the PL or TA, but did significantly increase SOL activation.
While the range of EMG activation levels were relatively small (TA: 0.6-10.1 ; PL: 5.8-36.6; SOL: 7.1-26.7), the authors recommended progressing ankle exercises from bilateral exercise on an exercise ball, to 1-leg stance on a Stability Trainer in combination with TheraBand elastic tubing to achieve progressively greater activation of ankle muscles.
REFERENCE: Borreani S, et al. Exercise intensity progression for exercises performed on unstable and stable platforms based on ankle muscle activation. Gait Posture (2013), http://dx.doi.org/10.1016/j.gaitpost.2013.08.006
Disclosure: Performance Health supported this study