David W. McMillan
David W. McMillan, Ph.D.
Assistant Professor | Director of Education and Outreach
I am a full-stack academician at the University of Miami Leonard M. Miller School of Medicine where I serve as Research Assistant Professor, Department of Neurological Surgery, and the Director of Education and Outreach at The Miami Project to Cure Paralysis. I conduct research by, with, and for people who have paralysis due to spinal cord injury (SCI). I consider myself a domain-general researcher specializing in a use-case not an approach.
My dissertation was about the role that the autonomic nervous system plays in the absorption, trafficking, and end-fates of dietary lipids. This might seem unrelated to other topics I study, such as climate health, but it seems to me that my interests share the common thread of being fundamentally about "systems and energy".
Maybe my lack of a single ontological category of study is because epistemically, the decision making process that directs my efforts is not entirely my own. I am committed to cultivating reciprocity throughout SCI research. I practice this participatory research in some of my studies, and help others to do so in theirs. To do so I co-founded and co-chair a "SCI Council" where council members with SCI provide researchers with advise on their studies at any point in the research cycle.
Outside of academia I am a daily bicycle commuter, a keen purveyor of many forms of adaptive outdoor recreation, a scuba diver and adaptive dive buddy, and a Board Member and Co-Chair of the Scientific Advisory Committee for Therapeutic Scuba Institute, Inc.
M.A. in Journalism, ongoing (proj. 2023)
University of Miami
Main Project: My project has yet to be determined, but tentatively will pertain to the development of a "science communication" curriculum for a course, and eventually (🤞) a degree track, to be taught through UM's School of Communication.
1° Mentor(s): Dr. Kevin A. Jacobs & Dr. Mark S. Nash
2° Mentor(s): Dr. James L.J. Bilzon
M.S. in Exercise Science, 2015
California State University, Los Angeles
1° Mentor(s): Dr. Christine J. Dy
2° Mentor(s): Dr. Ray De Leon
Main Project: My master's thesis was on the topic of "interappendicular neurological coupling", determining the role of arm-swinging during locomotor rehabilitation on patterns of muscle activity from paralyzed legs during assisted walking.
B.S. in Exercise Science, 2013
California State University, San Marcos
1° Mentor(s): Dr. Todd A. Astorino
2° Mentor(s): Dr. Jeff A. Nessler
Main Project: My bachelor's thesis pertained to the effect of rest interval on excess post-exercise oxygen consumption after resistance exercise, and then I instigated a study determining the effect of self-pacing on peak physiological response to cycling exercise.
Scientific Interests & Project
Neurological control of the transport, utilization, and storage of macronutrients
Stay tuned 😉
Diagnosis and management of cardiometabolic disease in people with spinal cord injury
My dissertation co-mentor, Dr. Mark S. Nash, was the committee chair for the inaugural efforts to construct the Consortium for Spinal Cord Medicine (CSCM) clinical practice guidelines (CPG) for cardiometabolic disease (CMD) in people with spinal cord injury and disorder (SCI). Furthermore, my postdoctoral fellowship was conducted with Dr. David R. Gater, a physician-scientist expert on the management and study of metabolic complications of SCI such as (but not limited to) obesity.
Understanding and augmenting sensorimotor function in people with spinal cord injury
Spinal cord injury (SCI) disrupts the transmission of signals between the brain and the final target tissues, such as skeletal muscle cells in the case of volitional motor control. Certain approaches to restoring function aim to either protect or restore the neuronal connections between the brain and the body via the spine. Maybe signals coming from the brain can inspire the nerve to regrow and/or make new connections. Well for restoration these descending signals are likely necessary, but certainly not sufficient (least people could will their way out of paralysis).
We must also remember that the spinal cord is not merely a conduit. The primary computational unit of the nervous system is the synapse, a junction between (not within) neurons. Since direct connection between the brain and muscles is rare, synapses in the spine allow for computation. As the now-old adage goes: the spinal cord is smart. Thus strategies for augmenting spinal output, with or without varying levels of input from the brain, are merited.
Understanding and diagnosing autonomic function after spinal cord injury
Surely we all appreciate our brains, but phenomenology alone does not lend itself to an appreciation of everything this amazing organ is doing. Along with the self-evident volitional—or somatic—processes that allow us to move and feel, our brains are conducting a silent orchestra to coordinate the many other bodily functions that don't feel to be under our control. Some of these functions occur via the autonomous action of organs: for example the pancreas has its own internal mechanisms for detecting sugar in the blood that it samples from the hepatic vein. But many of these bodily processes are, to some degree, augmented via signals from the autonomic nervous system that may or may not travel through the spinal cord. Autonomic neurological signals that do travel through the cord, such as the sudomotor cholinergic sympathetic efferents controlling dilation of blood vessels in skin capillary beds, are disrupted by spinal cord injury.
Maybe a clever measure of something external, like the surface of the skin, could allow us to understand the changes to the autonomic nervous system that are complex and otherwise subconscious.
Skeletal pathology within and beyond spinal cord injury
Both the rate and total magnitude of bone loss following spinal cord injury (SCI) exceeds that of unabated space flight. Clinically, this speaks to the importance of skeletal pathology in this population. SCI greatly increases risk of fracture in a manner that is unique to this population. Interestingly, lumbar spine bone density is largely preserved, and the most common fracture site—which is similar across all levels of injury—is the "knee region" (distal femur/proximal tibia). But physiologically, that bone loss in SCI exceeds what is observed in mechanical unloading alone is a hint. Bone are not just scaffolding.
Obesity and skeletal pathology in people with SCI: Narrative Review Paper
Spinal cord injury and subtropical coastal climate hazards
Florida’s sociogeographic, economic, and medical affordances have enticed a migration of persons with spinal cord injury (SCI) to this region. Specifically, Southeastern Florida is flat, snowless, has no State income taxes, and contains specialized medical centers. These conditions are advantageous given the mobility, medical, and monetary needs of individuals living with SCI, resulting in a robust community of those who have the means to relocate. Ironically, here in Southeastern Florida the conditions beneficial to living with SCI exist in one of North American’s prominent loci for coastal climate disasters. Yes, modern affordances in this region permit a long and well lived life with SCI; but external stressors resulting in deviations from standards of care quickly result in superimposed and intersecting risks to health and survival. Climatic hazards can impose deviations—such as disruptions of supply chains, alternations in access to energy and materials, and shifts in the type and availability of human resources required for care. In sub-tropical and tropical coastal areas, hurricanes have a disproportionate and often devastating effect on persons living with disabilities such as SCI.
Neurotherapeutic potential of psychedelic substances in people with spinal cord injury
I am leading an international team, self-titled the Neurotherapeutic Psychedelic Research Group, of academic medical professionals who are interested in this topic. We are considering the potential neuromotor and psychological effects of psychedelic substances in the specific use-case of spinal cord injury (SCI). There is existing evidence in basic and pre-clinical models for modulation and even regeneration of spinal neurons. In people, we are working on generating the first evidence for neuromodulatory effects in this population. Low volume (i.e., "microdose") or local (i.e., intrathecal) delivery could allow for neuromotor benefits without perceptual "side effects." But we are also considering how to optimize "macrodose" approaches targeting psychological effects. Will substances interact with standard SCI pharmacopia? Will sitters need to be prepared for physical responses not seen in other populations? Ought at least one sitter be a person with SCI ("peer-sitting")? In the field of SCI, the topic of psychedelics has yet to be addressed. But the time is now.
Reported use of hallucinogenic substances in Spinal Cord Injury Model Systems registrants (ongoing study)
On the Potential Therapeutic Application of Psychedelic Substances in Spinal Cord Injury (flagship review in preparation)
Ongoing Extramural Funding
Postprandial fat metabolism following an acute exercise bout in persons with spinal cord injuries
Funder: Craig H. Neilsen Foundation (CNF) Spinal Cord Injury on the Translational Spectrum (SCIRTS)
Ongoing Intramural Funding
Using community-engaged research to launch climate change resilience from an inclusive design beachhead starting with Southeastern Floridians living with spinal cord injury (SCI)
Funder: U-LINK Resilience Challenge
Role: Principal Investigator
Peer-Reviewed Scientific Papers
McMillan DW, Correa MA, Astorino TA, Nash MS, Gater DR. Virtual strategies for the broad delivery of high intensity exercise in persons with spinal cord injury. Front Act Daily Living. 2021, e-pub ahead of print, 703816. doi: 10.3389/fspor.2021.703816
Jacobs KA, McMillan DW, Maher JL, Bilzon JLJ, Nash MS. Neither postabsorptive resting nor postprandial fat oxidation are related to peak fat oxidation in men with chronic paraplegia. Front Nutr. 2021, e-pub ahead of print, 703652. doi: 10.3389/fnut.2021.703652
McMillan DW, Kressler J, Jacobs KA, Nash MS. Substrate metabolism during recovery from circuit resistance exercise in persons with spinal cord injury. Eur J Appl Physiol. 2021,121,1631-40. doi: 10.1007/s00421-021-04629-0
McMillan DW, Henderson GC, Nash MS, Jacobs KA. Effect of paraplegia on the time course of exogenous fatty acid incorporation into the plasma triacylglycerol pool in the postprandial state. Front Physiol. 2021,12,626003. doi: 10.3389/fphys.2021.626003
McMillan DW, Maher JL, Jacobs KA, Nash MS, Bilzon JLJ. Physiological responses to moderate intensity continuous and high intensity interval exercise in persons with paraplegia. Spinal Cord. 2021,59(1),26-33. doi: 10.1038/s41393-020-0520-9
McMillan DW, Maher JL, Jacobs KJ, Nash MS, Gater DR. Exercise interventions targeting obesity in persons with spinal cord injury. Top Spinal Cord Inj Rehabil. 2021,27(1),109-20. doi: 10.46292/sci20-00058
McMillan DW, Maher JL, Jacobs KA, Mendez AJ, Nash MS, Bilzon JLJ, Effects of exercise mode on postprandial metabolism in humans with chronic paraplegia. Med Sci Sport Exerc. 2021,53(7);1495-504. doi: 10.1249/MSS.0000000000002593
McMillan DW, Maher JL, Jacobs KA, Mendez AJ, Nash MS, Bilzon JLJ. Influence of upper-body continuous, resistance or high-intensity interval training (CRIT) on postprandial responses in persons with spinal cord injury: study protocol for a randomised controlled trial. Trials. 2019,20(1),497. doi: 10.1186/s13063-019-3583-1
Astorino TA, Schubert MM, Palumbo E, Stirling D, McMillan DW, Gallant R, Dewoskin R. Perceptual Changes in Response to Two Regimens of Interval Training in Sedentary Women. J Strength Cond Res. 2016,30(4),1067-76. doi: 10.1519/JSC.0000000000001175
Astorino TA, McMillan DW, Edmunds RM, Sanchez E. Increased cardiac output elicits higher V̇O2max in response to self-paced exercise. Appl Physiol Nutr Metab. 2015,40(3),223-9. doi: 10.1139/apnm-2014-0305
Astorino TA, Schubert MM, Palumbo E, Stirling D, McMillan DW. Effect of two doses of interval training on maximal fat oxidation in sedentary women. Med Sci Sports Exerc. 2013,45(10),1878-86. doi: 10.1249/MSS.0b013e3182936261
Astorino TA, Schubert MM, Palumbo E, Stirling D, McMillan DW, Cooper C, Godinez J, Martinez D, Gallant R. Magnitude and time course of changes in maximal oxygen uptake in response to distinct regimens of chronic interval training in sedentary women. Eur J Appl Physiol. 2013,113(9),2361-9. doi: 10.1007/s00421-013-2672-1
Nessler JA, McMillan D, Schoulten M, Shallow T, Stewart B, De Leone C. Side by side treadmill walking with intentionally desynchronized gait. Ann Biomed Eng. 2013,41(8),1680-91. doi: 10.1007/s10439-012-0657-6
Text Book Chapters
Maher JL, McMillan DW, Nash MS. The Cardiometabolic Syndrome in SCI: the Role of Physical Deconditioning and Evidence-based Countermeasures. In: The Physiology of Exercise in Spinal Cord Injury. 1 ed. Taylor J, editor. New York, NY: Springer Nature; 2017. Chapter 10; p.199-216.
Some More Writing
My friend Jazz and I have this thing we call Accessibilizing Our Future (AOF) where we put on the record our thoughts on the topic of sustainability and disability. I write primarily through the lens of energy and materials, focusing on coming necessity for reduced resource consumption and the implications that this simplification will have for people with disability.
Tweet Threads 🧵
SCI hurricane preparedness: https://anchor.fm/david-w-mcmillan/episodes/SCI-Hurricane-Preparedness-eu1rsb/a-a54eppc
Science Media Production & Organizing
Tag: A bench to bedside view of the landscape of spinal cord injury research and medicine, through the eyes of early career professionals.
Description: The American Spinal Injury Association (ASIA)'s Early Career Clinician and/or Researcher (ECRC) Webinar Series is "a bench to bedside view of the landscape of spinal cord injury research and medicine, through the eyes of early career professionals." This multi-part series features episodes focusing a single topic relevant to SCI research and medicine. In each episode, a dyad of presenters will grant us a "parallax perspective" on their SCI topic of expertise: ideally one perspective being more lab-focused and one being more clinic-focused. Each presentation will be 20 min with a following 10 min Q&A. Beyond sharing the emerging work of young professionals in the SCI space, we will also: (1) identify and archive the rising stars in this space, and (2) create a community for networking together these people based on a common mission. This series was founded and is organized/produced by Anne E. Palermo, Rahul Sachdeva, and me... in part with ASIA's Early Career Committee.
Tag: A dialogue from two perspectives on emerging scientific literature spanning the full spectrum of spinal cord injury research, from discovery to clinical application.
Description: The American Spinal Injury Association (ASIA)'s SCI Science Perspectives podcast disseminates the latest-and-greatest scientific work in the field of spinal cord injury (SCI) via a conversation with researchers that approaches their work from two perspectives: the “scholarly” perspective and the “community” perspective. First, ASIA’s Committees identify new and influential scientific papers relevant to the committee’s interests. Then the podcast host(s) interview the author(s) of the papers, approaching their project from each perspective. Then, the conversation from perspective is published as its own episode type. This podcast was founded and is produced by Suzanne L. Groah, Marla A. Petriello, and me... in part with ASIA's Communication Committee.
Description: This two and a half day conference will provide clinicians, researchers, and persons with spinal cord injury with the latest updates on research and clinical advances across a variety of topics related to spinal cord injury. Thursday and Friday will offer educational lectures/discussion approved for CME and CEU credits, on topics from advances in cell-based therapies for neural repair to recreational therapy for improved quality of life. A ½ day morning expo will be held on Saturday for those with spinal cord injury to try out adaptive recreational activities, learn about spinal cord injury community resources, and tour the new Christine Lynn Rehabilitation Center for the Miami Project to Cure Paralysis at UHealth/Jackson. CMEs and CEUs will be available to professionals who register and attend this conference.