Safe driving requires an ideal posture to bring comfort to drivers. A problem that commonly exists in driving is nonideal
driving posture, which can cause discomfort to the driver, especially when interacting with automotive pedals.
Research on contraction of Soleus muscle on driver's posture based on the knee angle more than 144º in a position of
pressing and releasing a pedal was conducted to investigate and overcome this problem. This is a field experimental
study and surface electromyography (sEMG) is used in collecting data on the Soleus muscle. The procedure of
collecting data on the Soleus muscle before and after experiments follows the Surface Electromyography for the
Non-Invasive Assessment of Muscles (SENIAM) recommendations. The result from the experiment shows that there is
a strong positive relationship between driver's postures in nature based upon the angle at the knee with Soleus
muscle contraction, where the Pearson correlation coefficient (r) is .990. While the temporal analysis measurements
based on Maximum Voluntary Isometric Contraction (MVIC) 60% in a position of pressing a pedal exceeding rms µV
25.34, and 25.47 respectively. On the other hand, MVIC 3% rms µV values: 1.18, 1.21 and 1.26 are obtained from the
position of releasing the pedal. The knee angle with Soleus muscle contractions is significant [F (1, 10) = 38.06,
p