Researchers have found an injection of a specific blood factor can replicate the benefits of exercise in the brain. They've discovered that platelets secrete a protein, exerkine CXCL4/Platelet factor 4 or PF4, that rejuvenates neurons in aged mice in a similar way to physical exercise. This protein, which is released from platelets after exercise, results in regenerative and cognitive improvements when injected into aged mice.
