A strenuous squat-lifting workout was the primary cause of 13 Iowa football players being hospitalized with a muscle disorder in January, a university investigation has concluded.
The investigation found the hospitalized players weren't responsible for their injuries and that the condition was not linked to use of drugs or supplements, according to the Des Moines Register, which obtained a copy of the report.
University of Iowa president Sally Mason was expected to formally present the results of the investigation Wednesday at a Board of Regents meeting.
The investigation, conducted by a five-person committee, found that the school's strength and conditioning staff did not intend to punish players during the Jan. 20 workout, which had been conducted successfully twice before but not after a three-week break from athletic activities.
The strength staff did reference close losses from the 2010 season and said the workouts would determine "who wants to be there."
The players were hospitalized after some of them complained to medical staff after the workout. Their symptoms included soreness throughout the body and tea-colored urine.
They were diagnosed with rhabdomyolysis, a stress-induced syndrome that can damage cells and cause kidney damage. The 13 players were hospitalized starting Jan. 24-25, and all were released by Jan. 31.
According to the report obtained by the Register, the committee recommended that the football team should abandon the workout. Coach Kirk Ferentz previously has said the workout would no longer be used.
Other recommendations included testing for all players when a few develop symptoms from a workout, and finding better ways to determine potential complications from specific workouts.
"Interviews with the strength and conditioning coaches revealed that their intent for the workout was to put the team through a tough challenge that would strengthen their confidence," the report said. "The strength and conditioning coaches were aware of heat injury and dehydration, but they did not know about rhabdomyolysis until the cluster [of 13 players] occurred."
The strength and conditioning staff had met with players Jan. 18 and "stressed the importance of the upcoming workouts."
Iowa's report emphasized the need for better communication between players, strength coaches, athletic trainers and team doctors. A timeline included in the report shows three instances where players had discolored urine -- a primary symptom of rhabdomyolysis -- but didn't report it to staff.
It was only after a trainer found a player to have high blood pressure on Jan. 24 that the initial rhabdomyolysis diagnosis was made.
Players' parents interviewed by the investigators criticized Iowa's football coaches for poor communication about the situation. According to the report, "Some parents expressed anger and distrust as a result of this event and suggested that some of the coaches should have been suspended until the investigation was complete."
Ferentz said in a statement Wednesday that he had no explanation as to why players who did the January workout were injured when no problems were experienced by athletes in past years.
"It'd be nice to know why this time and not the other three times," Ferentz said, referring to the 2004 and 2007 workouts and one in 2000 that the committee report does not mention. "I was glad the committee was clear in saying that the players were not at fault and the staff was not at fault.
"We will not do that drill again. That's one thing we have learned for sure."
Athletic director Gary Barta said he will move forward with the committee's recommendations.
"Many of the things recommended are already things being recommended or we're going through," he said. "Everything is rational and makes sense."
Iowa opens spring football practice Wednesday. Ferentz said all 13 players have been medically cleared to participate.
Adam Rittenberg covers Big Ten football for ESPN.com. He can be reached at firstname.lastname@example.org. Information from The Associated Press was used in this report.