This category of questions is directly answered by observing the raw EMG trace of any activity. It is answered
on the nominal level by yes/no or on/off. Caution is needed to check that the quality of the EMG
baseline allows a clear identification of active EMG. Noise may not be interpreted as “increased tonus”.
The relevance of this fundamental question
may be underestimated or misunderstood. Not
only for neurological therapists asking if the patient
can access to a certain muscle, but also
for training professionals, this basic question
can quickly receive relevance. E.g. the incorrectly
assumed “postural” role of the M. glutaeus
maximus in regular upright standing, or
the lumbar spinal/pelvic “stabilization” function
of the M. rectus abdominis, two fundamental
misunderstandings derived from pure functional
anatomical considerations can quickly be
cleared by simply asking and measuring, if
these muscles are active or not in these given
tasks (Fig. 66).