Stanford Medicine study details molecular effects of exercise

Researchers at the School of Medicine have shown how exercise changes the body at a molecular level and have identified blood markers of fitness.

The test could complement treadmill tests, a more traditional clinical evaluation of fitness, and provide individuals with far more nuanced information about their body’s molecular response to exercise.

The blood test is an offshoot of a complex study conducted by a team of researchers that took hundreds of thousands of molecular measurements from a group of individuals before and after exercising.

“Everybody knows exercise is good for you, but we really don’t know what drives that at a molecular level,” said Michael Snyder, PhD, professor and chair of genetics. “Our goal at the outset was to conduct a highly comprehensive analysis of what’s happening in the body just after exercising.”

The team tracked molecular markers of a wide array of biological processes, such as metabolism, immunity, oxidative stress and cardiovascular function. Hundreds of thousands of measurements from 36 study participants provided a window into the sea of chemical fluctuations the body experiences during intense exercise. To the scientists’ knowledge, such comprehensive measurements of post-exercise molecular fluctuations have never been performed. What’s more, the team saw that the participants who were most physically fit shared similar molecular signatures in their resting blood samples captured before exercise.

“It gave us the idea that we could develop a test to predict someone’s level of fitness,” said Kévin Contrepois, PhD, director of metabolomics and lipidomics in the Department of Genetics. “Aerobic fitness is one of the best measures of longevity, so a simple blood test that can provide that information would be valuable to personal health monitoring.”

With the preliminary data, the team has created a proof-of-principle test, for which they’ve filed a patent application. The test is not currently available to the public.

A paper describing the study was published May 28 in Cell. Snyder, who holds the Stanford W. Ascherman, MD, FACS, Professorship in Genetics, and Francois Haddad, MD, clinical professor of medicine, are co-senior authors of the study. Contrepois shares lead authorship with postdoctoral scholars Si Wu, PhD, and Daniel Hornburg, PhD, and with clinical assistant professor Kegan Moneghetti, MD, PhD.

A flurry of change

Snyder’s team set out to better understand the molecular shifts that underlie changes in physical fitness. The gold standard of medical fitness assessments is a peak VO2 test, which measures a person’s peak oxygen consumption during intense exercise and uses the score as a proxy for aerobic fitness. But Snyder and his team wanted more detail — specifically, about the ways in which exercise initiates change at the molecular level.

Read about the whole research findings here.