Hemoglobin:
This protein is found in red blood cells and transports oxygen from the lungs throughout the body. It is composed of alpha and beta globin chains and a heme group that binds oxygen. (source)

Lactate dehydrogenase:
This protein is involved in the conversion between lactate and glucose. Specifically, it "catalyzes the interconversion of pyruvate and lactate." The rest of the mechanism involves the following: "Exercising muscles convert...glucose to lactate. Lactate is released into the blood and is eventually taken up by the liver. The liver converts lactate back to glucose and releases glucose into the blood. This glucose is then taken up by resting muscles, red blood cells, and other tissues." (source)

Angiogenin:
Angiogenin is the primary protein responsible for inducing the formation and growth of blood vessels. (source)