Biomedical Engineering Reference
In-Depth Information
Fig. 3.5
Muscle excitation
patterns for walking: group
average EMG linear envelopes
for GMAX (gluteus maximus,
adductor magnus), GMED
(anterior and posterior portion
of gluteus medius), IL (iliacus,
psoas), HAM (biceps femoris
long head, medial hamstrings),
VAS (three-component vasti),
RF (rectus femoris), BFsh
(biceps femoris short head),
TA (tibialis anterior), GAS
(medial and lateral gastroc-
nemius) and SOL (soleus),
(adapted from [
59
])
Energy expenditure is generally evaluated through the measurement of oxygen
consumption. We could imagine using oxygen consumption in a virtual environ-
ment in order to evaluate the performance of the user's actions in navigation tasks.
However, it involves wearing a mask, which can be too invasive for some users.
Other devices such as heart rate monitors can be used to indirectly evaluate energy
expenditure but they are very inaccurate unless some very restrictive protocols are
used.
