Oostendorp is a two-time Iowa Conference Coach of the Year and 2009 NWCA National Coach of the Year, leading the Kohawks to a second-place finish in 2008. His teams have consistently been nationally ranked and have been picked to be part of the NWCA National Duals the past six years. Oostendorp led the Kohawks to back-to-back fourth place finishes at the 2008 and 2009 NCAA Championships, the two highest finishes in school history. Oostendorp has coached 51 All-Americans during his time at Coe.
Oostendorp is a graduate of the University of Iowa, where he wrestled for legendary coach Dan Gable and graduated with a B.A. in sociology in 1993. At Iowa, Oostendorp was a four-year starter at heavyweight, where he posted an overall record of 108-26 with 40 pins. He was a two-time All-American and Big Ten Champion for the Hawkeyes, placing fifth and third in the NCAA Championships.

Oostendorp also has considerable international experience. He was a member of the United States Greco Roman National Team from 1993-1998. His redshirt freshman year at Iowa, he won the Fila Jr. Greco Roman National Championship and represented the U.S. in the Fila World Championships placing fifth. In 1995, Oostendorp won the US World Team Trials and competed for the United States in the 1995 World Championships in the Czech Republic. He was the 1996 US Greco Roman National Champion and was the Olympic alternate at 100 kilograms after placing second in the final Olympic Trials.