Polyester fabrics tend to hold onto body odors, even after cleaning in a washing machine. If you've already washed your polyester but it still has a bad odor, you will need to take some extra steps. The longer you wait to wash the clothing, the longer it will take to get the odor out. Wash polyester clothing as soon as you can after wearing it.
Purchase activated charcoal for deodorizing from a home improvement store or cleaning supply store. You'll find it sold usually in mesh bags or discs. If you can't find activated charcoal, go to the pet supply area and look for a bag of cat litter that states it contains activated charcoal.
Place the activated charcoal in a plastic container. Put the clothing in the same container. Make sure the clothing is dry first; if it is not, hang it to dry beforehand.
Close the lid and leave it overnight. Check on the clothing the next morning. If it still has some odor, leave it until the following day.
Remove the polyester clothing from the container. Put the clothing in your washing machine. Start filling it with warm water. Add detergent and a cup of baking soda to the wash and let the machine run through a full wash and rinse cycle.
Take the clothing out of the washing machine and check to make sure no more odor is present. If it is, run it through a wash and rinse cycle again, using the detergent and baking soda. Hang to dry or tumble dry low (or according to instructions on the garment label).