And clear patterns emerged. The levels of 147 proteins were strongly linked to people’s baseline fitness, the researchers found. If some of these protein numbers were high and others low, the resulting molecular profiles indicated how suitable some were.
More excitingly, 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 proteins related to people’s baseline fitness – prophesied to what extent the aerobic capacity of others would increase, if at all with exercise.
Finally, because aerobic fitness is so strongly associated with longevity, the researchers crossed the levels of the various fitness-related proteins in the blood of people enrolled in a separate health study that included mortality records and found that protein signatures suggest lower or greater fitness response also means shorter or longer life.
Overall, the results of the new study suggest that “molecular profiling tools can help tailor” training plans, said Dr. Robert Gerszten, professor of medicine at Harvard Medical School and head of cardiovascular medicine at Beth Israel Deaconess Medical Center, who conducted the new study with its lead author, Dr. Jeremy Robbins and others.
For example, a person whose protein signature in the bloodstream suggests that he or she may be getting some fitness from a standard, moderate walking, cycling, or swimming routine may be pushed toward higher-intensity training or resistance training, said Dr.
This area of research is still in its infancy, however, he and Dr. Robbins. Researchers will have to study far more people with far greater differences in their health, fitness, age and lifestyle to zero on which proteins matter most to predict a person’s training response. Researchers also hope to come back and find out where these molecules come from, to better understand how exercise rebuilds our bodies and casts our health. Expect more and more refined results within a few years, said Dr. Gerszten.