Blood Test to Predict Aerobic Fitness Under Development

A simple blood test may be able to determine how physically fit you are, according to a new study conducted by scientists at the Stanford University School of Medicine. The test could complement treadmill tests and provide individuals with far more nuanced information about their body's molecular response to exercise.

"Everybody knows exercise is good for you, but we really don't know what drives that at a molecular level," said Michael Snyder, Ph.D., senior co-author of a paper published in Cell today. "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.

"It gave us the idea that we could develop a test to predict someone's level of fitness," said Kévin Contrepois, Ph.D., co-lead author of the study. "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."

According to Snyder, because the molecular profiling done in the study was so thorough, it wouldn't be practical for doctors to use in their clinics; it would be expensive and provide more information than necessary. But his team is working on whittling down the biomarkers to those that are most representative of a person's fitness level in an effort to make the test practical for broader use. As the researchers continue to optimize the fitness test, they hope it can one day be a faster, cheaper and more convenient way for people to objectively measure aerobic fitness.