THREE-TIME Olympic champion Jason Kenny is considering piling on the kilograms to aid his bid for glory at the Rio de Janeiro Games.

The 26-year-old Bolton track star exited the men's Keirin on day two of the Track World Championships in Saint-Quentin-En-Yvelines, near Paris, admitting that his bigger rivals had more power.

Kenny, Olympic sprint champion in London and twice team sprint gold medallist, has worked hard to gain muscle mass in recent years, but still weighs in at 81kg.

His rivals are considerably bigger and similar in size to Sir Chris Hoy, the now-retired Olympic Keirin champion, who was 94kg at his ideal race weight.

"I just don't seem to have the horse-power against the big guys," said Kenny, who has two world titles, in the 2011 sprint and 2013 Keirin.

"It's something we need to look at potentially, in the Keirin. It's not a new thing.

"I always make hard work of the Keirin. I very rarely get through the first round. Even when I won the worlds (in Minsk in 2013) I came back through the reps (repechage)."

Kenny, whose championships got off to a disappointing start when he was in the Greater Britain sprint team that finished a disappointing eighth, has to consider all three sprint disciplines, with the three-man, three-lap team sprint a priority, as he weighs up whether to try to add further muscle mass.

"I don't know, haven't decided yet (on getting bigger)," he said.

"Anyone can put 10kilos on if you put your mind to it. I don't know whether it would be useful weight or not.

"(But) I've never been very good at gaining weight, not useful weight.

"I'm sure I could gain a little bit more. This year I have gained a bit and I think it's helped me. We'll find out in the sprint. Hopefully I do a better qualifying."

Kenny fell into the Keirin repechage, offering a second chance of progression to the semi-final, after finishing sixth in a "nightmare" heat where he "was just a spectator on the back".

Just one rider advanced at the second attempt and Kenny could finish only second to Russia's Nikita Shurshin.

The result was contested by the British coaches, but Kenny knew he had been eliminated.

"When Shurshin came over he was a little bit tight and I just had a little bit of a hesitation, because I wasn't sure if he was going to shut me off completely," the Briton added.

"The commissaires decided, probably quite rightly, that it didn't affect the outcome of the race, because he was coming over like a freight train anyway.

"It's our job to question it. The rules do state that you're not allowed to go into the sprinters' lane if there's someone already there.

"(But) he was going so fast I've just got to accept that I was outgunned on that one."

Kenny will return in the individual sprint, which begins today and concludes on tomorrow's final day.

His larger rivals have an advantage in the flying 200metres qualifying discipline, which seeds riders for the head-to-head knockout races.

Kenny often qualifies low down the order and is occasionally eliminated. When he advances, his race craft helps.

"I'm going well," he said. "I thought I was going well coming up to this and was quite optimistic, as was the whole team.

"So far it's not happened. Maybe we can change that in the sprint."