MCMINNVILLE -- The final two McMinnville High School football players hospitalized with mysterious arm ailments have been released from the hospital.
Dozens of players started to suffer severe swelling and pain during an in-school retreat at the school last week that included workouts several times a day.
The hospital released creatine blood test results to players and their families. The parent of one injured athlete said his son's test showed low levels of the enzyme, but there was no evidence it came from a supplement.
Creatine is legal and can be found in supplements, as well as certain foods, like meat and fish. The body also produces it naturally.
At least 31 players showed symptoms and several had to have surgery to relieve the swelling, called Compartment Syndrome. The cause of the medical problems was still under investigation.
Football practice started back up again on Monday afternoon at McMinnville High School, despite last week's medical scare during a full immersion football camp.
Oregon School Activities Association executive director Tom Welter said the organization's medical committee will investigate and make recommendations to the executive board after its next meeting in September. The OSAA oversees school sports in the state.
The district said the work-outs by first year head coach Jeff Kearins were not unreasonable. Kearins said he did not suspect supplements or stimulants were to blame.
Medical experts were scratching their heads about what caused the the triceps muscles of the players to swell.
Players showed high levels of an enzyme called creatine kinase, which is a sign of vigorous exercise. The enzyme should not be confused with the over-the-counter supplement that is generically called creatine.
Test results should start coming in next Wednesday to help determine if McMinnville High School football players have a body-building supplement called creatine in their blood, said Rosemary Davis, spokeswoman for Willamette Valley Medical Center.
This is extremely unusual, said Dr. Michael Koester who is chairman of sports medicine for the Oregon School Activities Association. Millions of kids that participate in high school athletics year after year and this is the first case I ve heard, in doing this in the past 20 years.
The school district brought in experts to analyze first year head coach Jeff Kearins workouts.
From all we've obtained we don't believe the workout was unreasonable, said Superintendent Maryalice Russell.
Many of the players agree. We only worked out for 30 minutes at a time, nothing hard, just light work, said Jacob Montgomery one of the hospitalized players.
So how did several dozen players fall ill?
Newschannel 8 learned blood testing was underway to see if the players have high levels of the nutritional supplement creatine. It s something popular with professional football players. It is not illegal. Blood test results were due backWednesday.
There have been some case reports that have associated creatine intake with Compartment Syndrome, said Koester.
Several parents and players maintain their kids never took the creatine supplement.
Dennis Nice has two sons hospitalized with the syndrome. He said the kids just started working out together last week and didn t take any special supplements.
Dr. Koester wonders if something like creatine may have been hiding in something innocent.
All supplements are unregulated. There s nobody that defines what s actually in them, so if you go and pick up a new protein powder at the local health food store it's not regulated, said Koester.
KGWReporter Kyle Iboshi contributed to this report