Study 1

Purpose
The purpose of this study is a) to assess the effects of an 8 week strength training program on stress reactivity as measured by salivary cortisol, and b) to examine moderators for the effects of strength training on stress reactivity such as sex, attendance, and strength gains

Method

Participants: Participants are 60 Duke students who are previously sedentary. Students are randomly assigned to the treatment or control group.

Exercise Treatment: Treatment participants will perform a full body strength training program 3 days per week for 8 weeks. The small group strength training sessions will be led by a certified personal trainer.

Measures: At baseline and follow-up, participants will complete a battery of questionnaires and provide salivary cortisol samples immediately prior to and following the Trier social stress task. The questionnaires will assess current exercise level (International Physical Activity Questionnaire-IPAQ) and psychological distress (Brief Symptoms Inventory-BSI). The Trier social stress task involves participants doing a brief presentation and a serial subtraction task in front of “expert” judges and their peers.

 

Study 2

Purpose

The purpose of this study is a) to examine whether exercise is associated with changes in mood, body image, and eating disorder symptoms, b) whether changes are moderated by exercise parameters such as type or intensity, c) and whether changes are moderated by participant characteristics such as exercise motivation, baseline exercise level, health status, and other demographic factors.

Method

Participants: Participants are 300 students enrolled in Duke Physical Education (PE) classes. The PE classes are categorized into three exercise types: 1) cardiovascular conditioning, 2) strength training, and 3) mindfulness-based.

Measures: Participants will complete a brief battery of questions at the beginning, middle, and end of the semester. These questions will assess body image, depression, anxiety, eating disorder symptoms, and demographics.