About Us
Our Mission
We wrote Staying in the Game with a shared mission: to empower individuals to achieve sustained performance and long-term vitality by applying the principles of lifestyle medicine to both training and real life.
Both authors have seen firsthand how chronic disease, fatigue, and poor recovery can erode performance—whether on the battlefield, in competition, or in high-pressure professional settings. This book reflects our deep commitment to promoting performance longevity—the ability to stay mission-ready over the decades.
Whether you’re chasing a personal best in your 40s, 50s, or 70s, or want to move with strength and joy as you age, we believe endurance and capacity can be optimized at any age.
With combined backgrounds spanning clinical and military medicine, human physiology, and decades of experience working with elite and age-group athletes, senior military leaders, and Fortune 500 executives, we know that peak performance isn’t a fleeting moment—it’s a lifelong pursuit, built on intentional daily choices around nutrition, recovery, movement, and mindset.
Staying in the Game isn’t about longevity for its own sake—it’s about extending your ability to lead, compete, contribute, and thrive. Through the lens of lifestyle medicine—including plant-forward nutrition, intelligent training, restorative sleep, circadian rhythm alignment, and stress resilience—we offer a practical, science-based blueprint for sustainable performance.l
Whether you’re a warfighter, weekend warrior, executive, or someone who refuses to accept the myth of accelerated decline, this book is your field guide to aging powerfully, performing sustainably, and showing up fully for every mission that matters.
Meet the Authors
Sharon McDowell-Larsen, PhD
Dr. Sharon McDowell-Larsen, PhD, is an expert in leadership performance and the benefits of lifestyle practices, with over 25 years at the Center for Creative Leadership. She helps senior leaders enhance cognitive function, health, and resilience through evidence-based strategies. Sharon holds a PhD in Exercise Physiology from the University of Nebraska-Lincoln, where her research focused on exercise and immune function. Her performance science background includes roles at the U.S. Olympic Training Center and teaching graduate courses at the University of Colorado.
A decorated endurance athlete, Sharon holds national championship titles in mountain biking, Nordic skiing, and triathlon—including off-road (XTERRA), winter, and IRONMAN formats. She is also an XTERRA and IRONMAN age-group world champion. Since making her IRONMAN debut in 1987, Sharon has remained a passionate and competitive force in the world of multisport racing.
A native of Southern Africa, Sharon currently lives with her husband Matt in Grand Junction, Colorado, where she embraces the outdoor lifestyle and takes full advantage of the region’s renowned mountain biking—both locally and on the trails of nearby Moab.
Dr. Regan Stiegmann
DO, MPH, FACLM, DipABLM
Dr. Regan Stiegmann is a nationally recognized leader in Lifestyle and Performance Medicine, a Fulbright Scholar, and a physician innovator driving systemic change across healthcare, human performance, and digital health. Board-certified in both Preventive and Lifestyle Medicine, she blends clinical expertise with visionary leadership to advance human-centered, high-impact care.
Dr. Stiegmann has served in diverse executive and advisory roles across academic, military, and private sectors, including as Chief Medical Officer and medical educator. Her work bridges public and private systems to integrate lifestyle-based solutions at scale, redefining how health is taught, accessed, and sustained.
A passionate change agent, she brings contagious energy and a deep commitment to restoring the art of medicine. A proud Colorado native, she finds joy in nature, music, photography, cooking, and the companionship of her beloved cats—Tortilla, Disco Donna, and the late Ladybird.
