Meet Our Research Faculty
Learn more about our faculty research projects and interests by using the links below.
Title: Assistant professor
Area of research: Exercise psychology and physical activity epidemiology
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.
Title: Professor and Chair
Area of research: Biomechanics; Human Movement Analysis
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.
Area of research: Biomechanics
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.
Title: Professor and Associate Chair
Area of research: Exercise physiology
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.
Title: Associate professor
Areas of research: Biomechanics, Ergonomics
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.
Area of research: Exercise physiology
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
Area of research: Exercise physiology
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.
Title: Assistant professor
Area of research: Exercise physiology
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.
Title: Associate professor
Area of research: Physical activity epidemiology
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.
Title: Assistant Professor
Area of research: Cardiovascular exercise physiology
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
Title: Assistant professor
Area of research: Exercise Psychology
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.
Area of research: Adapted Physical Activity
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
Area of research: Motor learning and control
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.
Area of research: Motor control
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.
Area of research: Health promotion and exercise and physical activity epidemiology
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