Physiological responses to exercise can be highly variable and, until now, unpredictable. According to an interesting new study involving over 650 men and women, the levels of particular proteins in our bloodstreams may predict how well one will respond to various exercise regimens.
The research has to be replicated and expanded, but it’s a good start toward a blood test that can tell us what sorts of exercise are best for us and if we’ll get more or less benefit from the same workout as our spouse, children, or other training partners or rivals.
Exercise response is a subject that should be explored more frequently and freely than it currently is. We all know how beneficial exercise is to our health. Numerous studies demonstrate that those who exercise live longer, are happier, and have a lower risk of various diseases than those who do not. However, those conclusions are based on wide averages. If you look closely at the research data, you’ll notice a wide range of response, from massive health and fitness increases in some people to none at all in others. (The same may be said about weight-loss regimens.)
Unfortunately, nothing about our bodies and lifestyles, including our genetics, presently indicates how we will respond to exercise. Identical twins with identical DNA, as well as persons who are equally thin, overweight, or aerobically fit at the outset of a new fitness program, might react significantly differently to exercises, according to research. For unknown causes, some people become fitter and healthier as a result.
Researchers at Harvard University, the Beth Israel Deaconess Medical Center in Boston, and other institutions were fascinated by these mysteries. The researchers have long been curious about how exercise impacts the molecular environment within the body, how those changes affect health, and how diverse those changes may be. In the new study, which was published in May in Nature Metabolism, they chose to test if particular compounds in people’s blood may be connected to how their physiologies react to workouts. The scientists looked to a wealth of information gathered during the large-scale Heritage project, which looked at activity and health in parents and their adult children. The Heritage research comprised blood samples and detailed laboratory assessment of people’s aerobic fitness, followed by 20 weeks of moderate aerobic activity and additional testing.
The researchers focused on the data of 654 men and women who had taken part in Heritage, spanning a wide variety of ages and races, and began testing their blood. They concentrated on the various complex protein molecules produced in various bodily tissues that, when released into the bloodstream, travel to and kick-start biological processes elsewhere, altering how effectively our bodies function.
The scientists began counting the quantities and kinds of thousands of proteins in each of the 654 people’s bloodstreams using cutting-edge molecular techniques. They then combined those numbers with information on everyone’s aerobic fitness before and after their five-month exercise program. The researchers discovered that the levels of 147 proteins were substantially linked to people’s baseline fitness. The resultant molecular profiles revealed how fit someone was if some of those protein counts were high and others were low.
A distinct collection of 102 proteins tended to predict people’s bodily responses to exercise, which was even more surprising. Higher and lower amounts of these molecules — few of which corresponded with proteins associated with people’s baseline fitness — predicted how much, if at all, an individual’s aerobic capacity would rise with exercise. Finally, because aerobic fitness is so strongly linked to longevity, the researchers compared the levels of various fitness-related proteins in the blood of people enrolled in a separate health study with mortality records, and discovered that protein signatures implying a lower or higher fitness response also indicated shorter or longer lives.
Overall, the findings of the new study suggest that “molecular profiling tools might help to tailor” exercise plans, according to Dr. Robert Gerszten, a professor of medicine at Harvard Medical School and chief of cardiovascular medicine at Beth Israel Deaconess Medical Center, who led the research with Dr. Jeremy Robbins.
Someone whose protein composition shows he or she would benefit little from a conventional, moderate walking, cycling, or swimming regimen, for example, may be steered toward higher-intensity workouts or resistance training, Dr. Gerszten suggested.