[4] Earlier in 2006 Longosiwa had competed at the junior category of the 2006 IAAF World Cross Country Championships, where he finished 13th,[5] but was later disqualified.

[6] He began competing on the senior circuit in 2007, coming sixth at the 2007 All-Africa Games and then running the 3000 m and 5000 m events at the 2007 IAAF World Athletics Final.

He set a 3000 m personal best of 7:30.09 at the Qatar Athletic Super Grand Prix in May 2009, finishing runner-up to Eliud Kipchoge in a time of 7:30.09 minutes.

In November, he ran the opening leg of the International Chiba Ekiden and won the first stage which helped the team to victory.

[13] Longosiwa was second in the 5000 m at the Shanghai Golden Grand Prix and secured a place on the Kenyan Olympic team with a top three finish at the trials.