(AP) -- The parents of hospitalized former Iowa football star Brett Greenwood say he continues to fight and make improvements after collapsing during a workout earlier this month.

Greenwood, who was released by the Pittsburgh Steelers in early September, returned home and collapsed while working out at Pleasant Valley High in Bettendorf on Sept. 9.

Greenwood was taken to a Bettendorf hospital and later transferred to University of Iowa Hospitals and Clinics in Iowa City.

Michele and Dave Greenwood released a statement through the University of Iowa on Wednesday, saying they've been overwhelmed by the outpouring of support they've received.

The Greenwoods didn't disclose further details of Brett's condition.

The 23-year-old Greenwood started at safety for Iowa from 2007-10.

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