Millions of people already choose running as their preferred form of exercise because of its wide range of mental and physical health benefits. However, new research has added more reasons to lace up your sneakers. In addition to burning fat, relieving stress, and improving endurance, running has now been linked to stronger bones and an improved immune system.
In the new study, conducted by the Sean Morrison Laboratory at UT Southwestern, a team of scientists identified that forces generated when walking or running are transferred to bone-forming cells. The researchers found that a signal is conducted along the arteriolar blood vessels and directed to the marrow within the bones. This makes it easier for new bone to form and thicken. In addition, the bone-forming cells release growth factors that lead to more B and T cells and improve your ability to fight off infections. It seems that bone-forming cells feel the pressure caused by body movements (also known as mechanical forces) and this is what leads to the positive effects.
“As we age, the environment in our bone marrow changes and the cells that are responsible for maintaining bone mass and the immune function of the skeleton become depleted. We know very little about how this environment changes or why these cells decrease with age, ”said Sean Morrison, Ph.D., director of the CRI and investigator at the Howard Hughes Medical Institute. "Previous research has shown that exercise can improve bone strength and immune function, and our study discovered a new mechanism by which this happens."
The study, first published on Nature.com, used mice to show that when pressure-sensitive cells were deactivated, their bones became thinner and less able to clear bacterial infections. The scenario was then reversed by placing exercise bikes in the cages so the mice could exercise. This was the first indication that mechanical stimulation could regulate a niche in the bone marrow.
"We believe we have found an important mechanism by which exercise promotes immunity and strengthens bones, in addition to other mechanisms previously identified by others," says Morrison.