Swedish yacht EF Language, skippered by American Paul Cayard, has doubled its lead to more than 100 miles in the past 24 hours on the first leg of the Whitbread Round-the-World race.

Reaching speeds up to 30 knots on the journey to Cape Town, EF Language was 104 miles ahead of Monaco's Merit Cup early yesterday.

"The shuddering, not shaking, the violent jerking of the boat throws the people out of their bunks," Cayard said. "On deck you can't tell if this thing is a boat or a submarine."

Knut Frostad, skipper of third-placed Norwegian entry Innovation Kvaerner which led the fleet for more than two weeks, said he has been unable to get in the right position to pick up the favourable weather system helping EF Language.

EF Language has chosen a course 10 miles further south than Merit Cup and Kvaerner, which has hooked the yacht into a low pressure system.