Four weeks of daily slow-paced breathing did not confer additional performance improvements or physiological benefits when combined with sprint interval training, and unexpectedly produced a slight increase in nocturnal heart rate in the intervention group.
Sprint interval training significantly improved maximal power decrements and overall work output regardless of group assignment.
Slow-paced breathing did not produce additional performance gains beyond those achieved by sprint interval training alone.
Nocturnal heart rate showed a slight but statistically significant increase over time in the slow-paced breathing intervention group compared with the control group.
Slow-paced breathing was hypothesized to increase cardiac vagal activity and relaxation, thereby supporting recovery from the strong stress response elicited by sprint interval training.
Ten-minute sessions of slow-paced breathing following highly demanding sprint interval training offered limited value for enhancing performance or supporting recovery.
This research suggests that adding slow-paced breathing exercises to a four-week sprint interval training program does not provide extra benefits for recovery or athletic performance. The study recruited 34 participants who were randomly assigned to either a group that practiced slow-paced breathing after each training session and every evening before bed, or a control group that only completed the sprint interval training. Both groups improved significantly in measures of sprinting performance — such as maintaining power output and total work done — but there was no meaningful difference in improvement between the two groups. Measures of sleep quality and a key indicator of nervous system recovery (heart rate variability) also did not differ between groups. Surprisingly, the group that practiced slow-paced breathing actually showed a slight increase in nighttime heart rate over the course of the study compared to the control group. This was the opposite of what the researchers expected, since slow-paced breathing is generally thought to promote relaxation and lower heart rate. This finding suggests that the intense physiological stress caused by sprint interval training may have overwhelmed or counteracted any calming effects of the breathing practice. This research suggests that while slow-paced breathing has shown benefits in other athletic and health contexts, it may not be an effective add-on recovery tool specifically when combined with very high-intensity sprint interval training. Athletes and coaches considering breathing exercises as a recovery strategy following extreme-intensity training sessions may find limited additional benefit from this particular approach, at least over a four-week period with the protocol tested here.
Raidl P, Wessner B, Laister S, Csapo R. (2026). No Evidence for the Efficacy of Slow-Paced Breathing as a Recovery Strategy After Sprint Interval Training.. International journal of sports physiology and performance. https://doi.org/10.1123/ijspp.2025-0138