Hams was born in Hengelo, Overijssel to a Dutch father and Finnish mother and grew up in Vroomshoop.

Hams competed together with Wout Zijlstra in the World's Strongest Team competition in 2001 where they finished third.

Hams competed in the IFSA Strongman World Championships in 2005 in the qualifying heats and 2007 where he placed 12th in the finals.

[4] Jarno's brother Eric Hams has also competed in Strongest Man of the Netherlands on several occasions.

[5] Hams competes regularly in the Strongman Champions League series, achieving a podium finish in 2011 in the Canary Islands and in the Netherlands in 2012.