Apply antiperspirant/deodorant the night before, even if you plan to shower in the morning. Some studies indicate it works better that way.

Some metallic body odors don't seem to come from bacteria and there may not be much anyone can do about it, other perhaps than changing diet or other intake. It may be due to medications, supplements, etc. I've noticed a strong rusty or coppery metallic odor from some otherwise clean folks when they get hot and sweaty, even without working out.