Meet Our Research Faculty

Learn more about our faculty research projects and interests by using the links below.

Angelique Brellenthin

Title: Assistant professor
Area of research: Exercise psychology and physical activity epidemiology
Research projects:

My research primarily focuses on physical activity in the prevention and treatment of substance use disorders.  My research methods include both large cohort data analysis to investigate population-level relationships between physical activity and substance use as well as lab-based mechanistic studies to examine the effects of exercise on brain health and function throughout all stages of addiction.  A secondary research interest of mine is health behavior change.  Specifically, I examine how physical activity can help enhance the adoption of other healthy behaviors (e.g., quitting smoking) and how the principles of successful behavior change from addiction science can be applied to promote physical activity at the individual and population levels.    

Li-Shan Chou

Title: Professor and Chair
Area of research: Biomechanics; Human Movement Analysis
Research projects:

My research falls under general areas related to biomechanics and motor control of human movement, with focuses on the investigation of mobility impairments associated with ageing, musculoskeletal diseases or injuries, and traumatic brain injury. Below is a list of my current research projects.

  • Fatigue, Cognition, and Gait Balance Control – Fatigue is a prevalent symptom in work settings and often found in the older population. It negatively impacts the quality of life and associates with elevated mortality rates in the older population. In addition, cognitive dysfunction is another important intrinsic factor of fall accidents. This study is aimed to examine effects of fatigue, induced by a laboratory-based fatigue protocol or an occupational activity, on balance control, cognitive performance, and their interaction. 
  • Gait Function, Wearable Sensor Technology and Mild Traumatic Brain Injury (mTBI) – Objectives of this study are to identify acceleration-based biomechanical markers associated with mTBI related gait imbalance, develop an automated grading algorithm, and package gait analysis hardware and algorithms into a smart phone-based application easily and reliably employed in the clinical or forward deployed settings.

Tim Derrick

Title: Professor
Area of research: Biomechanics
Research projects:

Impact biomechanics. The Biomechanics Laboratory has close ties with industry in the area of impacts:

  • We have tested the cushioning properties of footwear for such organizations as Runners World Magazine, Consumer Reports, Fila, Air Walk, Remington, Speedo, Wilson, and the U.S. Military.
  • We have tested impact attenuation in gymnastics mats, vault tables, and pads for companies such as Hadar Manufacturing and American Athletics.
  • Shock attenuation has also been assessed in wheelchairs and basketball rims.
  • Current research in this area involves the effects that the geometry of the body during impact has on the effective mass and the impact attenuation.

Osteogenic exercise. Older adults and astronauts during long duration spaceflight have decreased bone strength that can lead to fracture. Exercise has been shown to increase bone strength and could be used as a preventative measure if the boundaries of safe and effective use can be identified.

We are using biochemical blood markers that are associated with bone resorption and formation in an effort to identify optimal patterns of impacts. We are also collecting impacts from various sport and exercise activities so that we can eventually identify those activities that produce the greatest osteogenic effect. The pattern of impacts can also play a role in stress fractures in athletes and military recruits. These are serious injuries that result in significant health care costs, lost training time, and interference with job performance and competition.

Lower extremity foot function. Foot disorders are difficult to study in humans because the foot is complex and resistant to internal examination. We have built a machine that allows us to move the muscles and skeleton of a cadaver foot in a natural motion so that we can measure bone movements and strains. We are working on using this information to build an accurate model of the foot so that function and dysfunction can be studied.

Panteleimon ‘Paddy’ Ekkekakis

Title: Professor
Area of research: Exercise psychology
Research projects:

I investigate the reasons behind what is presently considered the most serious public health challenge in industrialized countries, namely the problem of physical inactivity. In particular, my research examines the patterns of affective responses (such as pleasure versus displeasure) to exercise performed at different levels of intensity and the cognitive and physiological factors that influence these patterns. The rationale for this focus is based on the so-called hedonic theory of motivation, according to which people generally tend to do what makes them feel better and tend to avoid what makes them feel worse.

My research was the first to demonstrate a reliable dose-response relationship between the intensity of physical activity and affective responses. Specifically, along with my research collaborators and students, we have demonstrated that the pattern of affective responses varies systematically across three domains of exercise intensity:

  • Below the ventilatory threshold (a shift in respiratory gas exchange, manifesting as a breakpoint in the relationship between oxygen uptake and carbon dioxide excretion), affective responses tend to be positive in most participants.
  • Between the ventilatory threshold and the maximal lactate steady state (the highest intensity of exercise that permits a stabilization of blood lactate concentration over time), there is considerable interindividual variability in affective responses, with some individuals reporting positive and other reporting negative changes. Much of this variation can be attributed to personality dispositions and cognitive factors (such as self-efficacy for vigorous exercise).
  • Finally, beyond the maximal lactate steady state and until the point of maximal oxygen uptake, affective responses tend to be almost uniformly negative and show a strong relationship with physiological factors (such as respiratory variables and blood lactate concentration).

My research publications span the areas of psychometrics, personality and individual differences, affective psychology, psychophysiology, health psychology, behavioral and preventive medicine, applied physiology, and exercise science. I have co-edited the volume Psychobiology of Physical Activity (Human Kinetics, 2006), the first of its kind in the international literature.

Warren Franke

Title: Professor and Associate Chair
Area of research: Exercise physiology
Research projects:

My research interests are primarily centered on the cardiovascular system.  For many years, I focused on the relationship between emergency response personnel (law enforcement, firefighters), cardiovascular disease risk, and the mechanisms underlying this connection.

More recently, I have been working with Jim Lang (Kinesiology) as he leads efforts to understand better the mechanisms underlying how remote ischemic preconditioning affects the microvasculature.  For a number of years, I have been part of research efforts to develop better training methods for improving decision making under acute stress.  This has been in collaboration with research teams led by Nir Keren (firefighters; Agricultural and Biosystems Engineering) and Michael Dorneich (astronauts; Industrial & Manufacturing Systems Engineering).  Because of the inherent complexity and dangers associated with firefighting and spaceflight, we have been using virtual reality environment.   

Jason Gillette

Title: Associate professor
Areas of research: Biomechanics, Ergonomics
Research projects:

My research interests include injury mechanisms and injury prevention. I utilize video, force, and EMG measurements combined with musculoskeletal modeling to analyze human motion and estimate internal loading on the structures of the human body. Several current research projects are listed below:

Field-based exoskeleton assessments

Exoskeletons are an emerging technology but are difficult to assess using standard ergonomic techniques. We have tested passive shoulder support exoskeletons in field-based settings using electromyography (EMG) to quantify effects on muscle activation and fatigue. Field-based exoskeleton data collections have included John Deere and Toyota manufacturing sites, along with Emcor and Granite Construction work sites.

Lab-based exoskeleton assessments

While field-based studies provide ‘real world’ data, lab-based studies allow for systematic testing that can be applied to predictive models. We use IMU, video, or observational data to determine job task movements and duty cycles in occupational settings. These job tasks are then matched with lab-based EMG values for postures, tool weights, and exoskeleton usage to predict fatigue risk.

Anterior Cruciate Ligament (ACL) injury risk

Biomechanical factors such as jump landing entry and exit angles are manipulated to determine their effects on ACL injury risk. In addition, neuromotor control risk factors such as decision making and response time during the directional jump landing movements are tested through dynamic visual cues. The goal is to gain insight into ACL injury mechanisms and how we might train to prevent such injuries.

Doug King

Title: Professor
Area of research: Exercise physiology
Research projects:

My current research interests include studies on the metabolic adaptions of muscle to acute and chronic exercise. I have published more than 50 scientific articles relating to the following:

  • Nutritional aspects of exercise
  • Exercise in altered environmental conditions
  • Biochemical adaptations of skeletal muscle to sprint and endurance exercise
  • The use of exercise in the prevention and treatment of diabetes mellitus

Marian Kohut

Title: Professor
Area of research: Exercise physiology
Research projects:

My research is focused on factors that modulate the immune response to viral infection or vaccines. In particular, my laboratory is currently studying how aging impacts the immune response to influenza viral infection and influenza vaccine. We aim to understand:

  • The impact of age on factors important in Type I interferon induction (TLR7 expression, signal transduction)
  • How Type I interferon-induced modulation of dendritic cell or T cell function is altered by age.

Currently, we are seeking to identify the mechanism(s) by which moderate exercise improves resistance to influenza infection and minimizes inflammatory responses within the respiratory tract in aged populations (a five-year project funded by National Institute of Allergy and Infectious Disease).

We have recently completed another NIH-funded study demonstrating that moderate aerobic exercise in older adults improves antibody response to influenza vaccine, minimizes the age-related decline of T-cell immunity, and reduces inflammatory factors (CRP, TNFα,IL-6, IL-18). This study found that the improvements associated with exercise appear to be independent of psychosocial factors such as depression and stress.

Other exercise-related studies in my laboratory focus on intense, prolonged exercise (typically performed by competitive athletes), and how this type of exercise may compromise immunity resulting in increased vulnerability to infection. Our additional ongoing work also funded by NIH is focused on studying how botanical products (Echinacea, St. John’s Wort, and Prunella) may improve the immune response to viral infection and/or limit inflammation.

James Lang

Title: Assistant professor
Area of research: Exercise physiology
Research projects:

My research interests include examining peripheral autonomic and microvascular function in humans in an effort to understand how thermoregulation and blood flow control is altered with aging or cardiovascular disease.  Our lab uses skin as an in vivo model to assess mechanisms of microvascular function.

Microvascular Function Alteration with Age and Sex:  Cutaneous vasoconstrictor and vasodilator mechanisms are blunted in older individuals.  Not only does that have implications for susceptibility to cold- and heat-related illness, but it may also portend the progression of vascular dysfunction.  Our objective is to target key mechanisms that contribute to this impairment in aged skin and identify strategies to preserve vascular function.

Remote Ischemic Preconditioning (RIPC):  Brief, repeated bouts of limb blood flow occlusion have been shown to induce cardioprotection from ischemia-reperfusion injury. Our objective is to examine the mechanisms underlying this protective effect as well as how these putative benefits translate to clinical populations.  Furthermore, we are examining RIPC as an intervention to maintain cardiovascular health during prolonged spaceflight.

Duck-Chul Lee

Title: Associate professor
Area of research: Physical activity epidemiology
Research projects:

My primary research interests focus on physical activity epidemiology, especially on the independent and combined effects of aerobic and resistance exercise on various health outcomes in adults and older adults. Since 2009, I have been actively involved in more than 100 publications in peer-reviewed medical journals using the collected or available data from large observational (cohort) studies and randomized controlled trials of exercise. These studies include the associations/effects of physical activity, exercise, cardiorespiratory fitness, muscular strength, and dietary pattern with various health outcomes, including hypertension, type 2 diabetes, obesity, hyperlipidemia, falling, depression, sarcopenia, and cardiovascular disease morbidity and mortality.

Wesley Lefferts

Title: Assistant Professor
Area of research: Cardiovascular exercise physiology
Research projects:

My research in the Clinical Vascular Research Lab focuses on two interrelated topics: 1) understanding vascular mechanisms of aging and their role in influencing brain and the heart, and 2) identifying vascular mechanisms through which exercise benefits the brain and the heart. Within this area, I have particular interests in large artery stiffness and brain blood flow, and how differences in vascular function between men and women in middle age influence later-life brain and heart health (described below). Our lab utilizes non-invasive vascular techniques to assess heart function, blood flow, artery stiffness, and cognitive function to address these research avenues. Some specific interests and topics include:

Understanding vascular mechanisms behind the protective effects of exercise on the brain: It is widely established that exercise benefits the brain and protects against later-life Alzheimer’s disease and dementia, but the mechanisms behind this protection remain elusive. Increasing evidence suggests that cardiovascular health is tightly connected to brain health. As such, our goal is to identify the role of large artery stiffness and pulsatile (i.e. discontinuous) brain blood flow in the protective effects of exercise in the brain in middle-aged adults.

Examining sex differences in vascular mechanisms of brain health: Alzheimer’s disease is forecast to impact nearly 14 million adults by 2050, with women impacted 2.5 times more than men. The mechanism behind these sex differences in brain health and Alzheimer’s disease risk is unknown but may be related to vascular health in middle age, a critical window during which vascular health is highly related to later-life brain health. Our goal is to examine sex differences in vascular mechanisms governing brain blood flow (artery stiffness, endothelial function) in men and women during middle age to identify vascular targets that can be utilized for preventive efforts (pharmaceutical, behavioral/lifestyle interventions) to reduce sex differences in Alzheimer’s disease that disproportionately burden women with advancing age.

Additional interests: Other research areas I am interested in include: high altitude physiology and the effects of high altitude on cerebrovascular and cognitive function, high altitude research expeditions (e.g. Everest base camp), cardio-/cerebro-vascular effects of firefighting, impact of different types of exercise (resistance, HIIT, aerobic) on vascular/cognitive function, vascular mechanisms of depression, effects of COVID on cerebrovascular and cognitive function, neurovascular coupling in health and disease, early vascular aging, and trying to identify new techniques to get my Siberian husky puppy to actually listen to me.

Please see Dr. Lefferts’ lab webpage for more information

Jacob Meyer

Title: Assistant professor
Area of research: Exercise Psychology
Research projects:

Exercise and depression. My Wellbeing and Exercise Laboratory investigates the association between exercise behavior and depressive symptoms. In particular, past research has examined the short-term effects of single exercise sessions on mood states as well as the population-level data evaluating regular exercise as a protective factor for the development of depression. In addition, my work in this area is focused on two key components:

  • Determining the potential for exercise to be used in the treatment of clinical depression
  • How exercise exerts its influence on depression and other mental health conditions (i.e. what are the mechanisms that link exercise to mental health?)

Additional topics. Further topics that my laboratory works on include the effects of exercise on cognitive function, the interplay between anxiety and exercise, and the utility of exercise in both inpatient and outpatient contexts for treating mental health conditions.

Andy Pitchford

Title: Assistant professor
Area of research: Adapted Physical Activity
Research projects:

My research focuses on preventing health disparities among individuals with developmental disabilities including Down syndrome and Autism Spectrum Disorder, across the lifespan. Many individuals with developmental disabilities experience poorer health than the general population, due at least in part to experiencing barriers for participating in physical activity. My work utilizes the World Health Organization International Classification of Functioning, Disability and Health (ICF) framework to examine systematically these health disparities and to identify targeted interventions for health promotion. My research focuses on three key areas:

  • Examining the dynamic relationships between motor behavior, physical activity, and health outcomes (e.g., obesity) among individuals with developmental disabilities.
  • Improving measurement practices for research in specialized populations.
  • Designing, initiating, and testing community-based interventions to promote motor development, physical activity, and health among individuals with developmental disabilities.

Current research projects include:

  • Interrelationships between balance, movement competence, physical activity, and obesity among elementary-school-age children. This study includes children with Autism, Down syndrome, and typical development.
  • Prevalence of osteosarcopenic obesity in adults with Down syndrome and associations with physical activity and diet.

Ann L. Smiley

Title: Professor
Area of research: Motor learning and control
Research projects:

My research is focused on how the brain contributes to effective movement, with the long-range goal to impact remediation, rehabilitation, and therapeutic practices.

My current focus is the role of movement sequencing in children with Developmental Coordination Disorder and Developmental Dyslexia and the neurological control of movement sequencing and language. I am also involved in collaborative work in which we are examining interventions that impact executive processing in children.

Elizabeth Stegemöller

Title: Associate professor
Area of research: Motor control
Research projects:

My main research focus is to understand  the neurophysiology associated with the therapeutic effect of music in persons with Parkinson’s disease (PD).  Current studies include examining the effects of singing in persons with PD and examining the effects of music on motor cortical activity. I use a variety of techniques from kinematics to electroencephalography and transcranial magnetic stimulation in my research. I also offer multiple outreach programs for persons with PD which further informs my research. 

Spyridoula Vazou

Title: Associate professor
Area of research: Exercise psychology
Research projects:

My research focuses primarily on motivating children and adolescents to be physically active with the ultimate goal of preventing childhood obesity. To fulfill this objective, my research activities are centered around three main themes:

  • The dynamic nature of peer relationships and interactions in exercise and physical activity environments (in the classroom, in physical education, and in youth sport) that influence children’s motivation and behavior,
  • Integrating physical activity with academic lessons in the classroom and its effects on cognitive function, motivation, and academic achievement, and
  • The relationship of physical activity with affect and motivation in normal-weight and overweight children and adolescents.

My work draws primarily from Achievement Goal Theory (Ames, 1992; Nicholls, 1989) and Self-Determination Theory (Deci & Ryan, 2000). My research was the first to tap the unique aspects of peer influence in achievement motivation and to assess the unique dimensions of the peer motivational climate by interviewing young athletes and developing the PeerMCYSQ, Ntoumanis & Vazou(2005). I recently collaborated with the Iowa Department of Education and developed the “Move for Thought” kit, which integrates physical activities with any academic subject in the elementary school classroom. Current research activities:

  • Examining the feasibility of classroom-based physical activities and their role on children’s motivation and academic achievement.
  • Examining the role of structured PE on behavioral control and PA levels in preschoolers.

I serve as a reviewer for several journals in the fields of sport and exercise psychology, physical education, and exercise science.

Gregory Welk

Title: Professor
Area of research: Health promotion and exercise and physical activity epidemiology
Research interests and priorities:

Research Interests: My research interests focus on the assessment and promotion of physical activity in different settings and populations. Accurate assessments of physical activity behavior are needed to evaluate the health effects of physical activity, to identify relevant behavioral correlates, to monitor patterns and trends, and to evaluate behavioral interventions. Therefore, a fundamental component of work in the lab is on improving the validity and utility of various assessment methods. This work has emphasized the use of accelerometry-based activity monitors and potential applications of consumer-based monitors for research or facilitated health coaching applications.

Research Priorities: The focus of my research on physical activity and health promotion is on the use of implementation science methods to improve the translation and dissemination of evidence-based programs into practice. I serve as the director of the ISU Translational Research Network (U-TuRN) which brings together expertise from faculty, staff, and students across campus to address complex translational research challenges. The implementation science approach to research emphasizes the need to study programming in context so that it can be adapted and customized to meet local needs for enhanced translation. The projects below are two examples of translational studies coordinated through U-TuRN.

  • SWITCH (School Wellness Integration Targeting Child Health): This translational research project involved the dissemination of an evidence-based obesity prevention program called Switch. Through a USDA funded project, the research team transitioned the program to a capacity-building process that allows schools to lead programming on their own. The SWITCH program is actively managed by the 4-H arm of the ISU Extension network but ongoing research is evaluating the impact and outcomes.
  • Walk with Ease: This translational research project involves the dissemination of an evidence-based walking intervention across the state. The U-TuRN group has formalized a research collaboration with a non-profit agency called CHPcommunity that is positioned to facilitate clinical referrals to community programming through a coordinated state hub model. The Walk with Ease project is one prominent program but ongoing research will enable other evidence-based programs to be coordinated through the hub.

For additional information about other research and outreach programming coordinated through the Physical Activity and Health Promotion lab visit the department lab page or my personal lab web page