MHH researchers are studying biological aging processes in MMA fighters.
Blood draw at the gym: Research physician Dr. Kirsten Jahn, PhD, draws blood from Hugo Vach for her study. The MMA fighter from Fightschool Hannover will step into the ring on Saturday (May 16, 2026) at the OKTAGON 88 martial arts event in Hannover. Copyright: Inka Burow/MHH
Some people age faster than others. But how can biological age be reliably measured? A research team at Hannover Medical School (MHH) is investigating this question in a study on the biological clocks of martial artists who practice the full-contact combat sport of Mixed Martial Arts (MMA). Biological age can differ significantly from actual chronological age. Factors such as lifestyle, diet, exercise, and stress influence how quickly the body ages. The aim of the study is to identify reliable markers that can be used to determine biological age.
“To date, there is no clear-cut measure of biological age,” explains study leader Dr. Kirsten Jahn, PhD, from the Molecular Neuroscience Group at MHH Clinical Department of Psychiatry, Social- and Psychological Therapy. “In our study, we aim to identify biological age clocks that can accurately reflect a person’s state of health.” Such markers could enable preventive diagnoses and treatments.
Epigenetic Patterns as a Measure of Age
There is still no scientific consensus on exactly how biological age can be determined. One promising approach is so-called DNA methylation. This biochemical process influences which genes are active and which are not. To do this, cells attach small chemical markers—so-called methyl groups—to the DNA, which act like fine-tuning controls. They do not alter the genetic code itself, but rather its functionality. These epigenetic patterns change over the course of a person’s life. Researchers use these changes to draw conclusions about a person’s biological age.
The MHH team is relying on a new technology that simultaneously analyzes all relevant DNA segments capable of controlling gene activity through methylation—approximately 28 million so-called CpG sites. “This allows us to comprehensively evaluate the methylation pattern for the first time and more accurately decipher the epigenetic clock of aging,” explains Dr. Jahn.
MMA Fighters as an Unusual Study Model
MMA fighters provide an unusual but highly suitable model for research on biological age. They go through phases of rapidly changing physical and psychological stress—ranging from moderate training to intensive competition preparation to extreme stress before and during a fight. “MMA fighters are healthy individuals who are temporarily exposed to very strong influences that could have epigenetic effects on biological age,” says Dr. Jahn.
During the recovery phase, anti-aging factors such as light training and a normal diet tend to prevail. In the competition phase, pro-aging factors such as intense training loads and diets dominate. In the days leading up to a competition, fighters even restrict their fluid intake to reach their ideal weight class. The researchers suspect that these fluctuating stresses directly affect biological age clocks: during the recovery phase, they might tick more slowly; during the competition phase, more quickly—and become detectable in repeated blood analyses.
Research Between the Ring Doctor’s Office and Laboratory Analysis
“As a ring doctor, I have been accompanying MMA and other combat athletes for many years under a wide range of physical and psychological stresses,” says Dr. Panagiotis Karachalios, a specialist in orthopedics and trauma surgery well-known in the German and European MMA scene. “The study offers the opportunity to better understand how these stresses affect health and recovery in the long term, what conclusions can be drawn from this, and how we can further improve medical care for athletes in the future.”
Study participants can have MRI scans of their heads taken before and after fights. The researchers aim to use this to investigate potential injuries and changes in brain aging. Additionally, data on well-being, proteins, and metabolic products are collected. The research team compares these results with data from recreational MMA athletes who do not compete, as well as from healthy older adults. The analysis also incorporates existing markers of aging, including some less comprehensive “age clocks” as well as telomere lengths—that is, the length of the protective caps at the ends of chromosomes. The team is also investigating whether the combat sport strengthens psychological resilience.
Text: Camilla Mosel