Dhanurasana or the bow pose helps open up your chest region, promotes better breathing and increases lung capacity
Sit cross-legged. Inhale first from your left nostril while closing your right nostril with your thumb. Then exhale through your right nostril while closing your left nostril and repeat
The Chakrasana gives your chest and shoulder muscles a deep stretch which helps boost breathing
Sit cross-legged and inhale slowly through your nose. Breathe out slowly through pursed lips like you are blowing on something and repeat
Swimming increases lung capacity and strengthens your lungs over time