Nautilus, the American fitness company, saw its sales jump by 8.4 percent to $65.0 million for the fourth quarter, while its gross margin and income both improved markedly on the back of increased direct sales. The company ended the year with a sales increase of 7.5 percent to $193.9 million, and its income from continuing operations more than quadrupled to $10.6 million for the full year. Nautilus said that the tough retail environment reinforced the decision made last year to focus product development efforts on an entirely new range of cardio products.