Determinants of Dropout from and Variation in Adherence to an Exercise Intervention: The STRRIDE Randomized Trials.



This study aimed to characterize the timing and self-reported determinants of exercise dropout among sedentary adults with overweight or obesity. We also sought to explore variations in adherence among individuals who completed a 6- to 8-month structured exercise intervention.


A total of 947 adults with dyslipidemia [STRRIDE I, STRRIDE AT/RT] or prediabetes [STRRIDE-PD] were enrolled to either control or to one of 10 exercise interventions, ranging from doses of 8-23 kcal/kg/week; intensities of 50%-75% V̇O2 peak; and durations of 6-8 months. Two groups included resistance training and one included dietary intervention (7% weight loss goal). Dropout was defined as an individual who withdrew from the study due a variety of determinants. Timing of intervention dropout was defined as the last session attended and categorized into phases. Exercise training adherence was calculated by dividing weekly minutes or total sets of exercise completed by weekly minutes or total sets of exercise prescribed. General linear models were used to characterize the associations between timing of dropout and determinant category.


Compared to exercise intervention completers (n=652), participants who dropped out (n=295) were on average non-white (98% vs. 80%, p<0.01), had higher body mass index (31.0 kg/m2 vs. 30.2 kg/m2; p<0.01), and were less fit at baseline (25.0 mg/kg/min vs. 26.7 ml/kg/min, p<0.01). Of those who dropped out, 67% did so prior to the start of or while ramping up to the prescribed exercise volume and intensity. The most commonly reported reason for dropout was lack of time (40%). Notably, among individuals who completed the ramp training period, subsequent exercise intervention adherence did not waiver over the ensuing 6-8 months of training.


These findings are some of the first to delineate associations between the timing of dropout and dropout determinants, providing guidance to future exercise interventions to better support individuals at-risk for dropout.





Published Version (Please cite this version)


Publication Info

Collins, Katherine A, Kim M Huffman, Ruth Q Wolever, Patrick J Smith, Ilene C Siegler, Leanna M Ross, Elizabeth R Hauser, Rong Jiang, et al. (2022). Determinants of Dropout from and Variation in Adherence to an Exercise Intervention: The STRRIDE Randomized Trials. Translational journal of the American College of Sports Medicine, 7(1). p. e000190. 10.1249/tjx.0000000000000190 Retrieved from

This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.



Katherine Collins

Medical Instructor in Population Health Sciences

Katherine A. Collins, PhD, NBC-HWC, is a Medical Instructor in the Department of Population Health Sciences and affiliated with the Duke Molecular Physiology Institute at Duke University School of Medicine, and is a board-certified health and wellness coach. She studies barriers and predictors of health-promoting behavior change. The ultimate goal of her translational research is to design trials to optimize health-promoting behaviors for those at risk for "relapse" or ceased behavioral modification, in order to improve long-term health and well-being.


Kim Marie Huffman

Associate Professor of Medicine

Determining the role of physical activity in modulating health outcomes (cardiovascular disease risk) in persons with rheumatologic diseases (rheumatoid arthritis, gout, osteoarthritis)

Integrating clinical rheumatology, basic immunology, metabolism, and exercise science in order to reduce morbidity in individuals with arthritis

Evaluating relationships between circulating and intra-muscular metabolic intermediates and insulin resistance in sedentary as well as individuals engaging in regular exercise

Addressing the role of physical activity in modulating inflammation, metabolism, and functional health in aging populations


Ilene C. Siegler

Professor in Psychiatry and Behavioral Sciences

My research efforts are in the area of developmental health psychology and organized around understanding the role of personality in health and disease in middle and later life.

My primary research activity is as Principal Investigator of the UNC Alumni Heart Study (UNCAHS) a prospective epidemiologic study of 5000 middle aged men and women and 1200 of their spouses that evaluates the role of personality on coronary heart disease and coronary heart disease risk, cancer, and normal aging.

As head of Cancer Prevention Research Unit , I study the role of psychological factors related to mammography behavior and estrogen replacement therapy is being studied in UNCAHS women.


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Leanna Ross

Assistant Professor in Medicine

Dr. Ross's research focuses on understanding the mechanisms by which exercise interventions elicit short- and long-term cardiometabolic health benefits.  As cardiometabolic disease remains the leading cause of morbidity and mortality in the United States, the goal of her translational research is to enhance the development of evidence-based, precision exercise interventions that optimally prevent and treat disease.

Areas of Research Interest
Exercise dose-response and cardiometabolic health
Insulin action and glucose homeostasis
Legacy health benefits of exercise
Heterogeneity of response to exercise intervention
Precision lifestyle medicine
Epidemiology of physical activity and cardiorespiratory fitness



Elizabeth Rebecca Hauser

Professor of Biostatistics & Bioinformatics

The incorporation of personalized medicine to all areas of human health represents a turning point for human genetics studies, a point at which the discoveries made have real implications for clinical medicine.  It is important for students to gain experience in how human genetics studies are conducted and how results of those studies may be used.  As a statistical geneticist and biostatistician my research interests are focused on developing and applying statistical methods to search for genes causing common human diseases.  My research programs combine development and application of statistical methods for genetic studies, with a particular emphasis on understanding the joint effects of genes and environment. 

These studies I work on cover diverse areas in biomedicine but are always collaborative, with the goal of bringing robust data science and statistical methods to the project.  Collaborative studies include genetic and ‘omics studies of cardiovascular disease, health effects of air pollution, genetic analysis of adherence to an exercise program, genetic analysis in evaluating colon cancer risk, genetic analysis of suicide, and systems biology analysis of Gulf War Illness.

Keywords: human genetics, genetic association, gene mapping, genetic epidemiology, statistical genetics, biostatistics, cardiovascular disease, computational biology, diabetes, aging, colon cancer, colon polyps, kidney disease, Gulf War Illness, exercise behavior, suicide


Rong Jiang

Assistant Professor in Head and Neck Surgery & Communication Sciences

William Erle Kraus

Richard and Pat Johnson University Distinguished Professor

My training, expertise and research interests range from human integrative physiology and genetics to animal exercise models to cell culture models of skeletal muscle adaptation to mechanical stretch. I am trained clinically as an internist and preventive cardiologist, with particular expertise in preventive cardiology and cardiac rehabilitation.  My research training spans molecular biology and cell culture, molecular genetics, and integrative human exercise physiology and metabolism. I practice as a preventive cardiologist with a focus on cardiometabolic risk and exercise physiology for older athletes.  My research space has both a basic wet laboratory component and a human integrative physiology one.

One focus of our work is an integrative physiologic examination of exercise effects in human subjects in clinical studies of exercise training in normal individuals, in individuals at risk of disease (such as pre-diabetes and metabolic syndrome; STRRIDE), and in individuals with disease (such as coronary heart disease, congestive heart failure and cancer).

A second focus of my research group is exploration of genetic determinates of disease risk in human subjects.  We conduct studies of early onset cardiovascular disease (GENECARD; CATHGEN), congestive heart failure (HF-ACTION), peripheral arterial disease (AMNESTI), and metabolic syndrome.  We are exploring analytic models of predicting disease risk using established and innovative statistical methodology.

A third focus of my group’s work is to understand the cellular signaling mechanisms underlying the normal adaptive responses of skeletal muscle to physiologic stimuli, such as occur in exercise conditioning, and to understand the abnormal maladaptive responses that occur in response to pathophysiologic stimuli, such as occur in congestive heart failure, aging and prolonged exposure to microgravity.

Recently we have begun to investigate interactions of genes and lifestyle interventions on cardiometabolic outcomes.  We have experience with clinical lifestyle intervention studies, particularly the contributions of genetic variants to interventions responses.  We call this Lifestyle Medicopharmacogenetics.


exercise, skeletal muscle, energy metabolism, cell signaling, gene expression, cell stretch, heart failure, aging, spaceflight, human genetics, early onset cardiovascular disease, lifestyle medicine

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