Heart rate variability (HRV)

This study tests a 14-day home program called BraW-Day™ that combines brain exercises (like counting backwards) with walking, delivered via a smartphone app. Researchers want to see if doing both tasks together improves thinking, balance, and mood in athletes aged 18-40 who had a…

This study looks at whether listening to music can help lower anxiety in people having surgery for the first time. Researchers will measure heart rate, blood pressure, and anxiety levels in 90 adults. Some will choose their own music, others will listen to a standard playlist, an…

This study tests whether adding a controlled breathing program to a standard exercise routine improves heart and lung function in people with multiple myeloma. Twenty-six adults currently on treatment will take part in a 6-week program. One group will do breathing exercises at ho…

This study looks at what happens when people with pulmonary arterial hypertension, a condition that raises pressure in the lung's blood vessels, travel from their homes above 2600 meters down to sea level for a week, and then return. Researchers will measure heart rate variabilit…

Researchers are studying healthy adults who live permanently above 2600 meters, like in Quito, Ecuador. They will travel by bus to sea level for one week, then return to high altitude. The study measures heart rate variability, blood oxygen levels, and sleep patterns during the d…

This study looks at whether changes in heart rate variability (HRV) shortly after major abdominal surgery can help predict postoperative delirium—a state of confusion that can affect older patients. Researchers will measure HRV in 500 adults aged 65-85 before and within 24 hours …

This study looks at whether 5 minutes of slow, paced breathing (called coherence breathing) before a treadmill test can improve how the heart and lungs respond during exercise. Twenty recreationally active adults will try both slow breathing and normal resting before a maximal ex…

This study follows 60 adults with pulmonary hypertension (high blood pressure in the lungs) for 2 years. Researchers will measure breathing problems during sleep and heart rate changes to see how they relate to the disease. No new treatment is given; participants continue their u…