The fittest of the “Greatest Generation,” the now-elderly men who played varsity sports before serving in World War II, have a message for the younger generation: “Get off your duff, kid. Play sports – even if your school cancels phys ed classes – and you’ll still be in reasonably good shape at my age.”

In so many words, that’s one conclusion from a Cornell-Swiss Federal Institute of Technology analysis of health, lifestyle and longevity data from American veterans.

“Physical activity programs today are often hurt by budget cuts, leaving children with fewer or no opportunities to be active on a regular basis,” said Brian Wansink, Cornell’s John S. Dyson Professor of Marketing in the Charles S. Dyson School of Applied Economics and Management. “This study provides evidence for schools, youth centers and funding agencies: There are long-term, hugely positive benefits when children and adolescents engage in physical activities.”

Along with health scientist Simone Dohle at the Zurich, Switzerland, institute, Wansink reviewed results from a 2000 University of Illinois survey of surviving WWII veterans. Their report, “Fit in 50 years: participation in high school sports best predicts one’s physical activity,” was published in the December 2013 online journal, BMC Public Health.

To quantify health in aging seniors, Wansink and Dohle looked at the number of doctor’s visits reported by the elderly vets – by then in their late 70s and early 80s. Men with the fewest medical problems had one other thing in common: They played sports in school, before answering the call to military service.

And veterans with more doctor’s visits in 2000 reported being heavy smokers after the war – no thanks to all the free cigarettes handed out to GIs.

Thus, there might be one addendum to the veterans’ sage advice: “Save your lungs, kid, for the more important things in life.”