New research from Griffith University has found that simply warming the legs in hot water before exercise can significantly boost endurance in people with heart failure.
The study, published in the European Journal of Heart Failure, offers a promising non-drug option to help patients get more out of physical rehabilitation.
The research focused on people aged 50 to 80 who had a specific type of heart failure called heart failure with reduced ejection fraction.
This means their hearts are not pumping blood as effectively as they should, often leading to fatigue and poor exercise tolerance. Since regular exercise is important for managing heart failure, finding safe ways to improve exercise capacity is essential.
In this study, 22 participants underwent two different conditions. In one, they sat in warm water at 42°C (about 107.6°F) for 45 minutes, with their lower limbs submerged. In the other, they sat in cooler water at 30°C (about 86°F), which served as the control condition.
Afterward, the researchers measured how far the participants could walk in an endurance test similar to a “beep test,” which assesses physical performance by gradually increasing effort levels.
The results were clear: after the hot water treatment, participants walked an average of 201 meters farther than they did after the control condition. That’s a significant improvement, especially for people with heart failure who often struggle with even light activity.
The researchers found that heating the legs improved blood flow through the femoral artery (the main artery in the thigh) and boosted the amount of oxygen reaching the leg muscles. This made it easier for participants to exercise, likely because their muscles had more of the oxygen they needed to function.
Lead researcher Dr. Fergus O’Connor explained that this form of passive heating—meaning the body is warmed without physical effort—could be a simple and low-cost way to improve outcomes in cardiac rehabilitation programs. “By improving blood flow and oxygen delivery, lower-limb heating may help patients get more out of their rehabilitation,” he said.
Although the study looked at short-term effects, the team believes this technique could also help people with heart failure benefit more from long-term exercise training. Future studies will explore whether regular use of lower-limb heating can lead to lasting improvements in physical fitness and quality of life.
In summary, the findings suggest that a hot bath before exercise isn’t just relaxing—it could also be a powerful tool for improving endurance in people with heart failure. It offers a non-invasive, drug-free option that may make cardiac rehab programs more effective and help patients lead more active, healthier lives.
If you care about heart disease, please read studies about a big cause of heart failure, and common blood test could advance heart failure treatment.
For more information about heart health, please see recent studies about a new way to repair human heart, and results showing drinking coffee may help reduce heart failure risk.
The research findings can be found in European Journal of Heart Failure.
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