This thread discusses the Content article: Animal Flex (Universal Nutrition)

A question to you Animal Flex users who also have experience with cissus quadrangularis: which do you think would be better for helping my ailing left biceps tendon? I strained it a few months ago; it's getting better slowly, but is still hampering my workouts.

Interestingly, cissus is present in Animal Test (in an unknown amount as part of a proprietary blend), but not in Animal Flex. I am considering to try some bulk cissus. If you look on this website, Osteobolin-C rated very well for "joint/bone support" also, and that contains cissus.