Well the easy way to look at it is if glucose is a monomer then a polymer is a chain of glucose monomers. It's a storage form of glucose. Glycogen is a polymer and STARCH is a polymer. So they are talking about something like maltodextrin probably. Why they can't just call it that is beyond me

. Waxy maize strarch is another example.
It can be very useful in pre and post workout nutrition but as should be obvious it's not a weight loss aid.