Effect of Volitional Modification of Breath Frequency on Attention and Mood States: An Exploratory Randomized Crossover Study.

Background: Previously, yoga breathing improved mood states and attention but the effect of varying breath frequency on mood and attention was not clear.

Objectives: The objective of this study was to determine the effects of changes in breath frequency on attention, mood, vigor, and affect states.

Materials and methods: Thirty participants (mean age ± standard deviation, 27.3 ± 4.2 years) were assessed on 2 separate days practicing either high-frequency yoga breathing (HFYB, breath frequency 54.23/min) or bumblebee yoga breathing (BBYB, breath frequency 3.97/min) in random order. Assessments included blood pressure (BP), cancellation test scores, Nijmegen (to check for hyperventilation), respiration (rate, height of the breath wave [depth], and duration of inhalation relative to exhalation), mood states, vigor, and affect states.

Results: Diastolic BP increased after HFYB, whereas systolic BP decreased after BBYB, after both sessions scores in a cancellation test increased (changes in cancellation test performance suggest alertness and test-directed attention), also global vigor (signifying mental energy) and global affect (related to being "happy" and "calm") scores increased, whereas negative mood decreased after HFYB session (P < 0.05, Wilcoxon signed-rank test).

Conclusion: Both HFYB and BBYB increased attention test scores, possibly due to cortical activation (HFYB) or relaxation (BBYB). In HFYB, breath frequency and inspiration duration increased suggestive of increased sympathetic activity, accounting for increased vigor, positive affect, and diastolic BP. In contrast in BBYB, low breath frequency, higher breath amplitude, and prolonged expiration suggestive of parasympathetic activity may account for the decreased systolic BP after BBYB.