Asafa Powell: "I have to work harder"

Asafa Powell believes that the next few months will be among the biggest in his career.

The Jamaican sprinter will take part in the Aviva Grand Prix in Birmingham this afternoon as he steps up his preparation for the Olympic Games in London this year.

"It's an important year, a very important year," said Powell.

"Whatever we need to do to get ready and get in shape, we'll be doing it. Definitely I have to work harder."

Powell is a former world record holder over 100m.