Abstract: The present invention relates to an apparatus for exercising the human body comprising a stiff frame accommodating at least two guide tracks and at least one carriage in each guide track, at least one resistance unit, preferably attached to the frame, and for each carriage: a substantially inelastic cord drive system connecting said carriage with said at least one resistance unit, and an elastic cord drive system connecting the substantially inelastic cord drive system with the frame. Specific use of the apparatus according to the invention imitates the pattern of movements in cross-country skiing.