Cold-Water Immersion Improves Mood even with Short, Practical Exposure: Study

A recent study published in the journal of Lifestyle Medicine revealed that cold-water immersion is associated with significant mood enhancement across all tested exposure durations. Notably, a brief 5-minute immersion provides benefits comparable to longer sessions, making it a practical and time-efficient option. While the practice is generally safe for healthy, screened individuals in controlled settings, caution is necessary in unmonitored environments and for people with underlying medical conditions.

Cold-water immersion has become increasingly popular among wellness enthusiasts and athletes, who claim that plunging into cold water can elevate mood and reduce stress. Despite the rising popularity, recommended immersion times vary widely, and evidence on the most effective duration has been limited. The new research aimed to clarify whether longer immersions provide greater psychological benefits than shorter ones.

The study involved 140 participants who reported experiencing low mood but were otherwise healthy. Volunteers were randomly assigned to one of four groups: a control group or one of three cold-water immersion groups. Participants in the immersion groups entered seawater maintained at approximately 13.6°C for either 5, 10, or 20 minutes. Mood was measured using the Profile of Mood States questionnaire one week before and immediately after immersion. Control participants completed the same mood assessments without undergoing immersion.

These results showed that cold-water immersion significantly improved mood across all immersion groups, while the control group showed no meaningful change. The largest improvement occurred in participants who remained in the water for 20 minutes, followed closely by those immersed for five minutes. The ten-minute group experienced more modest improvements, though still statistically significant.

The participants who spent just 5 minutes in cold water showed a substantial reduction in overall mood disturbance, nearly matching the benefits seen in the 20-minute group. This research suggest this makes short immersions a realistic and accessible approach for individuals interested in trying cold-water therapy.

Skin temperature dropped by more than 10°C on average during immersion, while heart rate increased by roughly 33 beats per minute. In a subset of participants, heart-rate variability analysis showed a shift toward sympathetic nervous system activity, indicating activation of the body's stress-response system.

Overall, the findings suggest that cold-water immersion may serve as a simple mood-enhancing intervention, with short sessions offering a practical balance between effectiveness and convenience. Further research is expected to explore how long the mood benefits last and whether repeated immersions produce lasting improvements. 

Reference:

J. S. Kelly, N. Davidson, and J. P. Delaney, “ Improved Mood Following Cold-Water Immersion: A Comparison of Differing Exposure Durations.” Lifestyle Medicine 7, no. 2 (2026): e70048. https://doi.org/10.1002/lim2.70048