Air Conditioning. The gym MUST have Air Con.
"all workout programs must be approved by management"
I wish my gym had aircon and hotties in Lycra. Need to line the shed for aircon, not sure wife will approve of hotties though.
We lined the under side of the shed roof with insulation and installed some big fans.
The other thing we did was get some fly screens made so we can open the roller doors and drop them in to increase air flow and keep out insects (as best as you can with roller doors).
I think we are also lucky due to the height of the shed.
I wish my gym had aircon and hotties in Lycra.