Researchers determined polyester clothing smells worse than cotton following intensive exercise.

The material has a stronger smell because odor-causing bacteria grow better on polyester, the American Society for Microbiology reported

The researchers collected T-shirts from 26 healthy individuals after an extensive bicycle spinning session and incubated the shirts for 28 hours before having them inspected by a trained odor panel. The team also looked into the taxonomy of the bacteria on the shirts.

Fresh sweat rarely smells because the long-chain fatty acids the axillaries secrete are too big to be volatile. Bacteria break down these chains to "waftable"-sized odoriferous molecules. The team found the smelliest bacteria on the shirts was micrococci.

"They are known for their enzymatic potential to transform long-chain fatty acids, hormones, and amino acids into smaller-volatile-compounds, which have a typical malodor," Chris Callewaert of Ghent University, Belgium, said.

Staphylococci are known to create a non-malodorous body odor. "The micrococci are able to grow better on polyester," Callewaert said.

Corynebacteria are the primary cause of offensive body odors in the armpits, but rarely grow on textiles.

"BO is taboo, and its prevalence is greatly underestimated," Callewaert said. "There is little these people can do to help themselves. Some of them are too psychologically distressed to talk to strangers, or even to leave the house, afraid of what people might think of their smell."

Wearing cotton clothes could help reduce the smell of body odor. The researcher runs the website, drarmpit.com, and hopes to solve the body odor program altogether by transplanting microbes from non-malodorous relatives to those afflicted. For now the researcher suggests avoiding using antiperspirant, which can encourage the enrichment of odor-causing corynebacteria.

"That is what I have heard from people with BO - the more they use it, the worse it eventually got," he says. "But deodorants did not worsen the problem."