Bolt's training is going well according to his coach
Usain Bolt opened his 2010 season with victory in the 400m at the Camperdown Classic in Jamaica.
The 23-year-old Olympic and world 100m and 200m champion clocked a new meet record time of 45.86 seconds.
That shaved 0.49secs off than the previous best, set by Bolt in winning the same race in 2009.
Bolt said: "It was a good race - to run 45 seconds was a good sign. I never feel as good as I wanted. I guess I am getting there, I would say."
He added: "I just want to get my fitness up, I don't think I am where I would want to be."
Bolt's last run was in winning the 200m in September's IAAF finals in Greece.
Saturday's race is likely to be Bolt's only one at 400m after he pulled out of the University of the West Indies meet, which takes place next week.
Although current 400m world record holder Michael Johnson and others have suggested Bolt could lower the mark over the distance - currently 43.18 seconds set at the 1999 world championships in Seville - the Jamaican said his coach Glen Mills would have the final say as to whether he would push harder in the distance.
"That will be decided by the coach, and he has told me not to worry as if I am ever going to take up the 400m, he would design a brand new training programme for me.
"Right now I am just concentrating on the next world championships (in 2011) and Olympics (in 2012)."
Bolt also revealed there is a chance he will compete in the Commonwealth Games in India in October.
"My coach decides what I do, and he is putting a lot of thought into participating at the Games," he added. "I am not even sure when and where my first 100m race of the year will be."
Bolt's only announced competition on the new Diamond League circuit is a 100m race at the Adidas Grand Prix in New York on 12 June.