Evidence of ongoing brain injuries is present in football players at ages younger than previously thought.

Researchers from Orlando Health found in a new study that there is lasting evidence of brain injuries from repeated trauma to the head present in football players at an "alarmingly young age."

The study, published in the Journal of Neurotrauma , analyzed blood samples and neurocognitive assessments from Division I college football players in the NCAA to see if the players had biomarkers that indicated they had traumatic brain injuries, including concussions and subconcussive impacts, and to evaluate their neurocognitive function.

The results showed that the players had higher levels of these biomarkers than people who did not play football. Additionally, the biomarkers were present and elevated before football season began. Players with declining neurocognitive function had increased levels of the biomarkers indicating traumatic brain injury. Some players suffered from balance problems and poor reaction times.

Dr. Linda Papa, lead author of the study and emergency medicine physician at Orlando Health, said in a press release that the presence of these markers before the players suffered a hit or tackle during the season "suggests that the effects of past head injuries are persisting over time."

According to the study, "these markers could potentially serve as measures of neurocognitive status in athletes at risk for concussion and subconcussive injuries." They can be used to identify players at risk and treat them early, before serious effects occur.

Despite the presence of the biomarker, some of the players had never been diagnosed with a concussion. This may suggest that milder brain injuries, called subconcussive injuries, that aren't diagnosed by a doctor can still cause damage.