"I just started training three weeks ago and it felt great to come back.
"It was a bit of a cheeky race today because Ian and Kyle ... they just finished the Auckland Marathon three weeks ago. [This] gave me a handicap for my first race which is nice.
"They ran with tired legs after running the marathon which gave me a shot. It was awesome to be out there with the guys."
Ruthe said he enjoyed racing at this event and was considering coming back to do the Rotorua Marathon next year.
Rotorua runner Steven O'Callaghan said he struggled to get into a rhythm early on.
"It wasn't good for me ... I got through it that's the main thing. The conditions were perfect but I couldn't get on to the pace.
"It was a pace we should have been doing and what I should have been doing but I had a race last week and just didn't quite have it today," O'Callaghan said.
In a real upset, the women's division was won by Auckland 23-year-old Alannah Van Hout. In her second competitive race Van Hout roared home in a time of 1h 34m 47s, ahead of two Rotorua locals Karyn McCready (1h 34m 55s) and Steph McHale (1h 35m 23s).
Van Hout said: "It's pretty surreal. I used to hate running and then about a year ago I got into fitness and had my first half marathon about a week ago."
She was keen to come back next year.
In the Brooks 10km Classic, Chris Myland was the first male home in 36m 10s from Justin Copeland (+38s) and Dennis De Monchy (+2m 11s).
Lynmore's Sue Crowley was the first female home in 38m 44s followed by Siobhan Griffiths (+2m 41s) and Leah Purcell (+7m 28s).