EMG-Based Analysis of Treadmill and Ground Walking in Distal Leg Muscles

Differences between treadmill and ground walk-ing have been suspected by some authors. To check this hy-pothesis, the present study compared treadmill with ground walking in terms of surface electromyographic (sEMG) signal of Tibialis Anterioris (TA) and Gastrocnemius Lateralis (GL), from a large number (hundreds) of strides per subject. The analysis on seven healthy young adults showed no substantial variation in TA activity during treadmill walking, with respect to ground walking. An earlier and increased activity of GL during the transition between Flat foot contact and Push-off phases was detected during treadmill walking with respect to ground walking in terms of both the frequency of GL recruit-ment and area under the curve of GL profiles; this increase is likely to be related with the reported increase of magnitude of vertical forces during mid-stance in the treadmill compared with ground walking. Incorporating this findings into gait-analysis strategies could lead to a more accurate evaluation of results achieved by the use of treadmill.