Performance horses’ joints are subjected to extreme forces during both training and competition, and cartilage and joint fluid are often the first areas to show signs of wear and tear.Cartilage is the spongy, elastic material which covers the ends of the bones within a joint, acting as a major shock absorber and helping to reduce friction. Joint or synovial fluid should be thick and viscous, to bathe and lubricate the joint, also acting as a vital shock absorber.