I have used papain with some marinades for goat meat. Personally I do not care much for marinades any more, at least not long ones. For example, I used to marinate chicken overnight with spices and yogurt when making chicken tikka or tandoori chicken.
1 Pain at the base of the spine causes the psoas muscle to shorten and weaken(1,2,3,). 2  80% of Western people will suffer from debilitating backpain some time in their lives(5).  Western style walking (comfortable shoes & flat ground) fails to trigger muscles that stabilize hip joints & lower back.
It is the site of attachment of the calf muscle (gastrocnemius muscle) to the heel of the foot (the calcaneus bone). This tendon is vital for pushing off with the foot (this motion is known as plantarflexion). The Achilles helps you stand on your tiptoes and push off when starting a foot race.