active
aerobics
anatomy
body parts
burning
digestion
digestive system
do not digest
evidence
fibers
fitness
gymnastics
human
human body
human figure
illuminated organs
indigestion
inflammation
internecine
involuntary muscles
large intestine
liver
locomotor system
man
movement
muscle contraction
muscle lengthening
muscle tissue
muscle tone
muscles
muscular system
myofibrils
organs
pain
pancreas
person
physical
physical activity
physiology
postures
school
science
sculpted muscles
small intestine
stomach
strength
study
tendon
tenuous
transparency
voluntary muscles
xray