A method of achieving at least one result selected from the group consisting of (i) improved mitochondrial calcium uptake in muscle cells, (ii) improved utilization of calcium in muscle cells, (iii) increased mitochondrial energy in muscle cells, (iv) improvement in at least one of muscle functionality, muscle performance, or muscle strength, (v) decreased muscle fatigue, (vi) increased mobility and (vii) treatment of a muscle disorder linked to calcium depletion or deficiency, the method comprising orally administering to an individual an effective amount of a combination of calcium and at least one of oleuropein or metabolite thereof.