Aitken, John R., Gibb, Zamira, Mitchell, Lisa A., Lambourne, Sarah R., Connaughton, Haley S., De Iuliis, Geoffry N.. Society for the Study of Reproduction; 2012. Sperm motility is lost in vitro as a consequence of mitochondrial free radical production and the generation of electrophilic aldehydes but can be significantly rescued by the presence of nucleophilic thiols.