Objectives: Individuals with asthma frequently suffer with a decrease in quality of life. Yoga has been shown to improve autonomic function in the healthy population and has been used as an alternative therapy to help improve symptoms associated with various diseases.
Purpose: The purpose of this study was to assess whether 10 weeks of yoga training can improve quality of life and heart rate variability (HRV) in patients with asthma.
Design: Nineteen (19) females were randomly assigned to a yoga group or a control group for a 10-week intervention while still following guidelines established by their physician. All subjects answered the St. George's Respiratory Questionnaire (SGRQ) to assess quality of life and performed an isometric handgrip exercise test to assess HRV.
Results: Based on the SGRQ, significant improvements (45%, p < 0.05) in quality of life were observed with the yoga training, while no changes were found in the control group. Resting hemodynamic measures improved significantly in the yoga group compared to the control group (p < 0.05). The yoga group decreased parasympathetic modulation (HFnu [normalized units]) pre- to postintervention (0.45 ± 0.60 to 0.35 ± 0.06 nu, p<0.05, respectively) in response to the isometric forearm exercise (IFE), whereas the control group did not change. Additionally, the yoga group increased sympathetic (LFnu) (pre 0.47 ± 0.07 to post 0.60 ± 0.07 nu, p < 0.05) and sympathovagal modulation (logLF/HF) (pre 4.61 ± 0.39 to post 5.31 ± 0.44, p < 0.05, respectively) during IFE with no change in the control group.
Conclusions: Yoga training improved quality of life in women with mild-to-moderate asthma and resulted in decreased parasympathetic and increased sympathetic modulation in response to an IFE.