Press Room

San Diego, Calif., May 1, 2026 - The American Council on Exercise (ACE) announces new ACE-sponsored research, conducted by the Applied Exercise Science and Performance at Western Colorado University, examining the effectiveness of hot- and cold-water immersion as post-exercise recovery strategies. The study indicates that brief immersion in either hot or cold water—using temperatures easily achieved in a standard household bathtub—may offer more effective next-day recovery than passive rest alone. 

“Recovery plays a vital role in supporting performance and long-term physical activity participation, yet many people rely on recovery methods without clear guidance,” said Dr. Lance Dalleck, lead researcher and professor at the Applied Exercise Science and Performance. “With this research, we sought to better understand whether simple, accessible recovery strategies meaningfully influence performance outcomes.”  

The study compared hot water immersion (104°F / 40°C), cold water immersion (54°F / 12°C), and passive recovery following identical, high intensity workouts. Each water-based recovery protocol lasted 12 minutes and was completed immediately after exercise. 

Nine participants, men and women aged 16 to 50 years old, who were deemed healthy and physically active were selected for this study. Each participant completed three identical workouts designed to assess cardiorespiratory fitness, anaerobic power, and muscular fitness, and each workout was paired with a different recovery condition. Performance was reassessed 24 hours later to evaluate how each recovery method influenced performance the next day. 

Key findings from this study include: 

While the study’s small sample size (n=9) means the results should be interpreted cautiously, ACE views the findings as a valuable contribution to the evolving conversation around evidence-based recovery. 

“At ACE, our mission is to bridge the gap between research and real-world practice,” said Sabrena Jo, PhD ACE Senior Director of Science and Education. “This study reinforces that recovery strategies don’t need to be extreme, expensive, or inaccessible. What matters most is using methods that are safe, sustainable, and grounded in science and ultimately suited to the client’s preferences.” 

Read the full study in International Journal of Research in Exercise Physiology. 

About the American Council on Exercise (ACE) 

Since 1985, the American Council on Exercise (ACE) has been the leading non-profit education and certification provider for health coaches and exercise professionals in the United States and around the world. 

With more than 90,000 highly respected certified health coaches and exercise professionals, ACE Certified Professionals are on the ground daily helping people move, stay active and make lasting lifestyle behavior changes to build healthier communities. 

Headquartered in San Diego, ACE collaborates with public health partners to educate people of all backgrounds about the importance of physical activity and other healthy lifestyle behaviors; advocates for public policies to increase physical activity opportunities; and supports scientific research that investigates the efficacy of behavior-change interventions and the effectiveness of exercise practices and trends. Learn more at acefitness.org.