balanced ventilation system design

A ventilation system design has been proposed to develop a balanced mechanical ventilation system for a gym. The idea is to design the inlet air to flow from the bottom floor, and the exhaust air to be taken from the ceiling to create an air flow through the gym space to reduce heat and keep a high oxygen content. Gym area: 200 meters squared Gym volume: 740 meters cubed All other information will be provided upon request. I need fast accurate designs ready for construction. I need it ASAP.