PORTLAND, Ore. -- A team of state epidemiologists doubts that 24 McMinnville High School players who were hospitalized with swelling to their upper arms took a creatine supplement, but the investigators were unable to determine a single cause of their ailment.
The players fell ill last month following workouts in a sweltering weight room during first-year football coach Jeff Kearin's "total immersion" football camp. Three players required emergency surgery to their triceps to relieve pain caused by high pressure that impeded blood flow.
Five other players had muscle pain and creatine kinase levels 100 times the normal levels. The enzyme creatine kinase is released by muscles when they are injured and is not to be confused with the creatine supplement. Athletes and military recruits have shown high levels of creatine kinase after exercise.
Dr. Katrina Hedberg, lead investigator in the incident, said the intensity of the workout likely played a part in the injuries, and advised in the report that "intense, short-duration, repetitive resistance exercise involving a single muscle compartment can lead to serious health complications."
"If this exercise had been given to Olympic weightlifters, would they have been able to handle it? Probably," Hedberg said in a telephone interview.
But the report doesn't cast blame on any particular factor, and raises doubts that the players were using a creatine supplement, though the players were not specifically tested for the supplements.
"On preliminary review, (the Oregon Department of Public Health) did not find patterns suggesting an association with illness from specific prescription medications or nutritional supplements," the study says.
That corresponds with what the father of two players told The Associated Press. Dennis Nice, who has two sons who were hospitalized, said the report shows supplement usage wasn't an issue.
"Nobody has a definitive answer at this point," Nice said. "It sounds like there were all kinds of different factors, but creatine usage, supplement usage was not one of them."
At about 4 p.m. on Aug. 15, the team finished outdoor sprints and went inside a school wrestling room to perform intense, short-duration repetitions of chair dips -- which exercise the triceps muscle -- and push-ups for about five minutes at a time. The activity was described as a "team-building exercise" in the report, and noted that Kearin had used it on college players in the past without incident.
When players performed incorrectly, the entire exercise was restarted. The team spent 20-25 minutes in the room. Players also did not drink water made available to them, according to the report, and their dehydration went unrecognized.
Two days later, an assistant coach drove a player suffering from compartment syndrome -- the cause of the triceps swelling -- to a doctor's appointment. On Aug. 18, a day later, five more team members went to the hospital, including two others suffering from compartment syndrome.
On Aug. 20, after the team screened players and coaches for abnormally high creatine kinase levels, six players were hospitalized. Ten other players went to the emergency room and were released.
The report describes compartment syndrome in the upper arm as "extremely rare," and notes that the syndrome occurring after exercise is unheard of.