Professor Clarkson is a fellow in the American College of Sports Medicine (ACSM), and she has served as a member of the Board of Trustees. She served as President of the New England Regional ACSM Chapter, Vice-president of the National ACSM, President of the National ACSM, and President of the ACSM Foundation. She received the 1997 ACSM Citation Award, the 1999 New England ACSM Honor Award, the 2001 Excellence in Education Award from the Gatorade Sport Science Institute, the University of Massachusetts Chancellor's Medal in 1997, the 2005 National ACSM Honor Award, the University of Massachusetts Award for Outstanding Accomplishments in Research or Creative Activity, 2005, and the University of Massachusetts Graduate School Centennial Award, 2008. In 2007, she presented the keynote plenary Wolffe Lecture at the National ACSM meeting in New Orleans, attended by 5000 members.