 MONDOVI, Wis., Aug. 30, 2021 GLOBE NEWSWIRE -- Marten Transport, Ltd. NasdaqGS:MRTN announced that its Board of Directors has appointed Douglas P. Petit as its new President, effective today. Doug Petit will succeed Tim Kohl, who has served as the Companys President since 2008. Tim Kohl was recently appointed as Chief Executive Officer on May 4, 2021. 