What is Joint Effort? Joint Effort is an effective supplement containing high levels of Vitamin C. Vitamin C is a water soluble vitamin also known as ascorbic acid that has many beneficial properties, particularly within collagen formation and joint health. Why use Joint Effort? Joint Effort contains vitamin C which contributes to normal collagen formation, collagen is a protein found in bones, muscles, skin and tendons that provides strength and support. Vitamin C also contributes to bone formation reducing the risk of injury during impact sport. Alongside those fantastic benefits, vitamin C supports iron absorption and immune system function.