Body tissue proteins can help figure out the best exercise plan

If we all start the same exercise routine tomorrow, some will get a lot more conditioned, some will get a little more fit, and some might actually lose shape. Each person’s responses to the exercises can vary greatly and, until now, unpredictably.

But a study of more than 650 men and women suggests that levels of certain proteins in the bloodstream can predict whether and how we will respond to various exercise programs.

The research still needs to be replicated and expanded, but it represents a significant start toward a blood test that indicates the best types of exercise for each person, and whether we can get more or less benefit from the same workout as our spouse, children, and others. training partners or rivals.

Exercise response is a topic that should probably be discussed more often and openly than it is. We know that exercise is wonderful for our health. Numerous studies show that people who exercise tend to live longer, happier and with less risk of many diseases than sedentary people.

But these findings refer to broad averages. Looking closely at the study data, we can find a dizzying array of reactions, from massive health and fitness gains in some people to none at all in others. (The same goes for responses to weight loss programs.)

Unfortunately, little about our bodies and lifestyles predicts how we will respond to exercise, including our genetics.​

Identical twins with identical DNA can react quite differently to workouts, studies show, as can people who are equally thin, obese or fit at the start of a new exercise program. Some, for mysterious reasons, end up being fitter and healthier than others.

These conundrums have intrigued researchers at Harvard University, Beth Israel Deaconess Medical Center in Boston, United States, and other institutions. Scientists have long been interested in how exercise modifies the molecular environment within the body, how these changes influence health, and how diverse the changes can be.

Now, for the new study, published in May in Nature Metabolism, they set out to see if certain molecules in people’s blood might be related to how their physiologies react to workouts.

To find out, they first turned to the valuable body of data gleaned from the Heritage Foundation’s large-scale study, which investigated exercise and health in parents and adult children. That study included accurate laboratory tests of people’s aerobic fitness as well as blood draws, followed by 20 weeks of moderate aerobic exercise and more testing.

The researchers have now extracted records from 654 men and women who participated in the Heritage study, of varying ages and ethnicities, and have begun to take a deep look at their blood.

They focused on the varieties of large, complex protein molecules created in tissues throughout the body that, when released into the bloodstream, flow in and start biological processes elsewhere, affecting how the body works.

Using state-of-the-art molecular instruments, the scientists began listing the numbers and types of thousands of proteins in the bloodstream of each of the 654 people. Then they tabulated those numbers with data on everyone’s aerobic fitness before and after the five months of exercise.

Clear patterns emerged. Levels of 147 proteins were strongly associated with people’s basic physical condition, the researchers found. If some of these protein numbers were high and others low, the resulting molecular profiles indicated the person’s fitness level.

More intriguingly, a separate set of 102 proteins tended to predict people’s physical responses to exercise. Higher and lower levels of these molecules — few of which overlapped with proteins related to people’s basic physical condition — indicated how much, if any, one’s aerobic capacity would increase with exercise.

Finally, because aerobic fitness is strongly linked to longevity, the scientists cross-referenced the levels of various fitness-related proteins in the blood of people enrolled in a separate health study, which included mortality records, and found that protein signatures that imply lower or higher fitness response also meant shorter or longer lives.

Taken as a whole, the results of the new study suggest that “molecular profiling tools can help tailor” exercise plans, said Dr. Robert Gerszten, a professor at Harvard Medical School and chief of cardiovascular medicine at Beth Israel Deaconess Medical Center, who led the new study with its lead author, Dr. Jeremy Robbins, and others.

A person whose bloodstream protein signature suggests they can gain little fitness from a moderate routine of walking, cycling or swimming, for example, might be urged to do high-intensity exercise or resistance training, Gerszten said.

This area of ​​research, however, is still in its infancy, he and Robbins said. Scientists will need to study many more people — who have much wider disparities in health, fitness, age and lifestyle — to focus on which proteins are most important in predicting an individual’s reaction to exercise.

The researchers also hope to go back and discover where these molecules originated from, to better understand how exercise remakes our bodies and shapes our health. We will have more refined results in a few years, Gerszten said.

Translated by Luiz Roberto M. Gonçalves