***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: Sixteen studies involving 1233 participants with mean forced expiratory volume in one second (FEV1) 30% to 51% predicted were included. There was a significant improvement in six-minute walk distance after three months of yoga involving pranayama timed breathing techniques (mean difference to control 45 metres, 95% confidence interval 29 to 61 metres; two studies; 74 participants), with similar improvements in single studies of pursed lip breathing (mean 50 metres; 60 participants) and diaphragmatic breathing (mean 35 metres; 30 participants). Effects on dyspnoea and health-related quality of life were inconsistent across trials. Addition of computerised ventilation feedback to exercise training did not provide additional improvement in dyspnoea-related quality of life (standardised mean difference -0.03; 95% CI -0.43 to 0.49; two studies; 73 participants) and ventilation feedback alone was less effective than exercise training alone for improving exercise endurance (mean difference -15.4 minutes; 95% CI -28.1 to -2.7 minutes; one study; 32 participants). No significant adverse effects were reported. Few studies reported details of allocation concealment, assessor blinding or intention-to-treat analysis. Breathing exercises over four to 15 weeks improve functional exercise capacity in people with COPD compared to no intervention; however, there are no consistent effects on dyspnoea or health-related quality of life. Outcomes were similar across all the breathing exercises examined. Treatment effects for patient-reported outcomes may have been overestimated owing to lack of blinding. Breathing exercises may be useful to improve exercise tolerance in selected individuals with COPD who are unable to undertake exercise training; however, these data do not suggest a widespread role for breathing exercises in the comprehensive management of people with COPD.
Output:

Sixteen trials with 1233 participants were included, most of whom had severe COPD. The breathing techniques studied included pursed lip breathing (breathing out slowly with the lips in a whistling position), diaphragmatic breathing (deep breathing focusing on the abdomen), pranayam yoga breathing (timed breathing with a focus on exhalation), changing the breathing pattern using computerised feedback to slow the respiratory rate and increase exhalation time, or combinations of these techniques. The study quality was generally low. Breathing exercises appeared to be safe for people with COPD. Yoga breathing, pursed lip breathing and diaphragmatic breathing improved the distance walked in six minutes by an average of 35 to 50 metres in four studies. Effects of breathing exercises on shortness of breath and well being were variable. When added to whole body exercise training, breathing exercises did not appear to have any additional benefit.