Abstract: An exercise apparatus which supports a user in a semi-recumbent position and provides an arm pull/arm press assembly and a leg press assembly whereby the arm pull/arm press and leg press assemblies may be used simultaneously or independently of one another. The arm and leg press assemblies are each operable against variable air resistance means, and preferably against independent variable air resistance means such that the amount of resistance to the leg press exercise may be different or varied from that of the arm pull/arm press exercise.

Abstract: Novel cementitious systems comprised of gypsum, calcined clay, and clinker consisting essentially of hydraulic calcium silicates are disclosed which have the following properties: (1) a water demand of less than about 33% nc; (2) one-day strengths of at least about 1000 psi; and (3) low alkali functionality. By increasing the amount of calcined clay, the resulting cementitious system will sequentially gain the following properties: (1) alkali non-reactiveness; (2) alkali resistance; and (3) low chloride permeability. Novel methods of preparing the novel cementitious systems of this invention are also disclosed. The novel methods not only reduce production costs by decreasing fuel and raw material consumption, but they also allow the cement producer to proactively address significant environmental concerns related to the manufacturing process.