Olympic and world heptathlon champion Klüft skipped the indoor season after suffering leg cramps in a bid to remain injury free for the championships.
The decision appears to have paid off with the 23-year-old winning both the heptathlons she has competed in since her world title in Helsinki, Finland last August.
Olympic triple jump champion Olsson will just be glad to be competing at a major championship after missing last season with an ankle injury that needed four operations.
Olsson made his comeback after 21 months out in June and the 26-year-old has bounded back into form with the leading jump by a European this year of 17.62.
Kajsa Bergqvist along with fellow Swede Stefan Holm are favourites for the high jump titles.