The following 3 breathing techniques if practiced regularly can be beneficial for everyone to increase energy, and breath control. It also helps to lower stress, depression, and anxiety, so is beneficial for mental health. These techniques improve airway and lung function, that can increase resilience against conditions like COVID which affect breathing capacity and blood oxygenation. These are also of immense benefit for people with Asthma, Chronic Bronchitis (COPD), and other respiratory conditions.
1. Alternate nasal breathing: Pranayama is a well-known beneficial alternate nasal breathing (anulom vilom) technique. It can be practiced by sitting in a comfortable posture with back straight. Use the right-hand thumb to close your right nostril and take a long breath from the left nostril. Then remove the thumb from the right nostril and place the ring finger on the left nostril and slowly release the breath from the right nostril. 
2. Pursed-lip breathing: This is a useful breathing technique that helps to slow the breathing rate and reduce breathlessness. First, inhale slowly through the nose, and then exhale through tightly pressed (pursed) lips for twice as long as the time taken to inhale. This technique is not only helpful for exercise but may be beneficial during other daily tasks like lifting, bending forward, or climbing stairs.
3. Abdominal breathing: It is also called diaphragmatic or belly breathing. It is practiced by lying on the back on a flat surface with knees bent. One hand is placed on the upper chest and the other on the belly. Breathe in slowly through the nose, letting the air in towards the lower belly. The hand on the belly will rise, while the hand on the chest remains still. Then tighten abdominal muscles taking them inward and breathe out through pursed lips, making the hand on the belly move down to the original position. 
All the above breathing exercises should be done 2 hours post meals. Take a 20-second gap after every one minute of practicing any of these exercises, then start again. Initially practice for 5 minutes, increasing gradually to 10 minutes daily.
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3 Comments
Read the article again and felt good about its comprehensive and yet easy to understand quality. Can you clarify:
1. Is it ok to exercise early morning on empty stomach?
2. Is swimming good for asthma?
Yes it is fine to exercise in the morning empty stomach before breakfast.
Swimming is a very good exercise for asthma, however the water or the climate should not be too cold, as that can trigger broncho-constriction and breathlessness. Also if you are experiencing acute asthma symptoms, or a cold-cough, then avoid swimming.
Do read my post: https://drvarsha.com/10-points-of-care-during-physical-exercise-for-people-with-asthma/
The blog was a good read and really helpful and I would recommend this to all my friends and peers.