I tend to feel more focused and productive after a nice workout session, even if it’s on the shorter side. Research highlights how exercise can boost brain function across all ages, including improving executive function, problem-solving, and planning skills for those with ADHD. When you move your muscles, your brain will thank you.
Recently, researchers explored what certain molecules in the blood, known as metabolites, can tell us about an individual’s endurance and fitness, such as how far they can walk. Can physical fitness boost brain health and energy metabolism for older adults? How does blood chemistry differ between those who are more active and those who are less active? How is fitness linked to molecular changes? Here’s the research.
The study

In a study published in npj Systems Biology and Applications, elderly adults living in five retirement homes in Vienna, Austria, were placed into two groups: the active group and the less active group. The researchers analyzed the participants’ data and measured their walking distance, strength, and other factors. The researchers created a new Body Activity Index (BAI) to score fitness levels and analyzed participants’ physical performance, especially walking distance, and the chemical markers (blood metabolite levels) in their blood.
The results

I’ve covered lots of previous research on how exercise is good news for your metabolism, and this study reveals the same. Here are the results:
- Walking distance is the best indicator of overall physical fitness.
- Blood metabolite patterns are strongly associated with fitness. Researchers found a strong correlation between fitness scores and blood metabolite patterns.
- Interestingly, around 92% of the time, the machine-learning models were able to tell which individuals were “more active” or “less active” based on their blood metabolites, which is pretty impressive.
- Aspartate showed up repeatedly as the strongest metabolite marker of physical fitness. Those who were more active overall had different aspartate levels compared to those who were less active. What’s interesting about this is that aspartate plays a major role in energy metabolism and how your cells produce energy. Aspartate has also been associated with brain health and dementia risk.
- These differences in metabolite markers were also observed with aspartate aminotransferase (AST) — a liver-related enzyme involved in muscle activity and energy metabolism.
The takeaway

This study shows us that fitness really does prompt molecular changes in your blood that benefit your body and brain. Another takeaway is that your blood chemistry reflects your physical fitness, so much so that the machine-learning models were able to accurately detect who was more or less active based on their blood metabolites around 92% of the time. This adds to prior research concluding that exercise, including walking, boosts metabolism and yields positive changes at the cellular and molecular level.





