Both tests test the endurance and strength of muscle, but they evaluate muscles in different areas of the body. The curl-up test is used for the abdominal muscles while the arm hangs test, as is said in its name, test the arm muscles.
<span>Stiff and tight muscles can constrict nerves in the back. When these nerves are constricted, it can result in sensations of pain throughout the back, especially the lower back.
