TSAC Report 33 | Page 8

DENNIS SCOFIELD, MED, CSCS EFFECTS OF MILD TRAUMATIC BRAIN INJURY ON ANABOLIC HORMONES, EXERCISE, AND RECOVERY The views, opinions, and/or findings in this report are those of the author and should not be constructed as an official Department of the Army position, policy, or decision, unless so designated by other official documentation. Tactical athletes have a high likelihood of exposure to physiological strain and incurrence of stressors from performing physically demanding tasks in hostile and/or austere environments; the physical ramification of which may or may not be superficially observable (26). Thus, managing effective physical training programs for this population can create unique challenges for the tactical facilitator. In particular, the tactical facilitator must have a clear understanding of how injuries incurred during operations can impact physical performance and recovery. Mild traumatic brain injury (mTBI), also referred to as a concussion, is a common injury among both tactical and contact sport athletes and is defined as an impact, penetration, or rapid movement of the brain within the skull that results in an altered mental state and damage to the brain (31). The Centers for Disease Control (CDC) definition of mTBI includes head injuries with skull fractures, closed head intracranial injuries, and unspecified head injuries with periods of altered consciousness less than one hour (5). It is estimated that 1.7 million head injuries occur in the United States annually, and approximately 5.3 million children, women, and men are living with mTBI-related disabilities in the U.S. (25,31). In regards to military personnel, TBI rates have significantly increased in U.S. Soldiers and Marines over the last decade (14). There have been more than 287,861 diagnosed TBI cases since the year 2000, with the majority of cases being classified as mTBI and occurring in the non-deployed setting (8). In current deployed military operations, Elder and Cristian report that the most common cause of TBI is blast injury (9). Alarmingly, they further note that estimates of 20% of the first 1.2 million service members who served in Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) suffered a TBI; about 60% of whom were not assessed by a he