Initiator of Dafinitely.com is Daf Dubbelman. Also in his private life he is pushing boundaries and is a vivid sports fanatic

He has run various (ultra) marathons in various parts of the world. Personal best 2.56 for the marathon of Amsterdam. Most memorable marathons: the 90km Comrades ultra marathon South Africa, the marathon on the Chinese Wall, the North Korea Marathon, the Iran (I ran Iran) marathon dressed as a girl, and the New York Marathon (3 times). 
Full distance IronMan Triathlon personal best 10.02. 
Next challenge is the 250km Marathon des Sables ultra marathon in the Sahara desert.

Daf is a graduate of the Harvard Business School Owner President Management Program and passionate about instigating change and his nickname could be perseverance.