The physiological and psychological benefits of running have long been established with studies too numerous to mention, and we have known for some time that running can benefit bone strength and mineral content. But a new study out of the University of Ottawa shows that distance running benefits a part of the body we don’t necessarily associate with the sport: the bone marrow.
In babies, the bone marrow consists only of blood-producing cells, but as we age, the marrow’s blood-producing capacity decreases and the fat content increases. So the fat in bone marrow is a good indicator of bone health and relative age.
The study, which was published in the Journal of Bone and Mineral Research, looked at casual joggers (up to 30K per week), serious runners (around 60K per week), and serious cyclists (275K per week). It found that the joggers had significantly less fat in their marrow than a control group of sedentary people, but the serious runners had even less. (The cyclists’ bone marrow was unaffected.)
The study concluded a significant anti-aging benefit to runners’ bone marrow equivalent to one year for every nine kilometres per week that they run. So, for someone running 60K a week, their bone marrow is similar to that of someone 6.6 years younger.
As the lead investigator of the study, Dr. Guy Trudel of the Ottawa Hospital explained to CBC host Robyn Bresnahan on its Ottawa Morning show yesterday, “A runner is vertical and constantly and repeatedly loading their spine, in a cyclical way, whereas on a nice, smooth ride on a bicycle, the spine is more horizontal. You have absorption [of impact] from your tires, and you don’t have this repeated stress on your bone. So the conclusion is that the stress on your bone is important to keep your bone healthy and your bone marrow healthy and young as well.”
“Exercise is the best medication,” Trudel goes on, “and runners have this additional benefit.”