The Immediate Effect of Cold Spinal Spray and Cold Spinal Bath on Cognition Among Young Adults: A Three-Armed Randomized Controlled Trial

Background Cognition is a complex process that involves acquiring knowledge and understanding. Hydrotherapy, a part of naturopathy, particularly cold spinal spray and cold spinal bath, is used to influence physiological responses. However, its immediate effects on cognition remain unexplored. This study aims to evaluate the immediate effect of cold spinal spray and cold spinal bath on cognition among young adults using a three-armed randomized controlled trial. Methods A total of 90 healthy volunteers (aged 18-25 years) were recruited and randomly assigned into three groups: group 1 - cold spinal spray (n=30), group 2 - cold spinal bath (n=30), and group 3 - control group (n=30). Interventions were administered for 15 minutes. Cognitive assessments were conducted pre- and post-intervention using the Stroop test and Letter-Digit Substitution Test (LDST). Heart rate variability (HRV) was measured as a secondary outcome. Data were analyzed using Jamovi version 2.7.6 statistical software (the Jamovi Project, Sydney, Australia). Results Both cold spinal spray and cold spinal bath groups demonstrated statistically significant improvements in cognitive performance, including increased accuracy and reduced error rates, compared with the control group (p<0.05), with large effect sizes observed for primary cognitive outcomes (η²≥0.14). The cold spinal spray group exhibited a more pronounced improvement in cognitive scores compared to the cold spinal bath group. HRV analysis showed enhanced autonomic regulation post-intervention most in the cold spinal spray group. Conclusion Cold spinal spray and cold spinal bath have an immediate positive effect on cognitive functions, with cold spinal spray demonstrating a slightly greater impact. These findings suggest the potential of hydrotherapy in enhancing cognition and the scope of these applications to patients with cognitive decline.