An exercising device includes a first strap (1), loops (3, 7) attached to the first strap (1) and an anchorage element (11) that is intended to be fixed to a base, the anchorage element (11) being designed to receive the first strap (1) in such a way that the first strap (1) is displaceable in its longitudinal direction relative to the anchorage element (11). It is significant that at least one loop (3, 7) has such a length/circumference that it may be mounted around the body, e.g. the waist of the chest, of a user.