After the Dutch Judo Federation has decided to centralize their program, he became head coach men and women and head of the National Training Centrer at Papendal. He was coach of Henk Grol, Marhinde Verkerk and Kim Polling.
He was also coach of the team with: Benito Maij, JP Bell, Michael Bazynksi, Garmt Zijlstra, Akkie Muilwijk, Zeger van Oirschot and Matthew Purssey
Results
The results of Arens as coach
2005: Guillaume Elmont and Dennis van der Geest World champion Cairo Egypt, Bronze Mark Huizinga
2007: Ruben Houkes World champion in Rio de Janeiro Brasil, bronze Guilaume Elmont
2009: Henk Grol Vice- World champion Rotterdam The Netherlands
2010: Dex Elmont and Henk Grol both Vice Worldchampion Tokyo Japan
2011: Dex Elmont vice World champion Paris France
2012: Henk Grol bronze Olympic games London England
2013: Henk Grol Vice World champion and Dex Elmont Bronze Rio de Janeiro Brasil
2018: Guusje Steenhuis Vice World champion Baku Azerbaidjan , Marhinde Verkerk and Juul Franssen Bronze medals (not match coach).
2019: Noel van T End World Champion Tokyo Japan, Juul Franssen, Roy Meyer and Michael Korrel Bronze medals (not match coach).