We practice Yoga to come out of suffering. One significant source of suffering is being in a constricted space. The Sanskrit word dukha refers to this. Many translate the word dukha as bad space.
We often create constricted spaces for ourselves with our thoughts, by being stuck in past events. When something traumatic happens there is a tendancy to repeat this event and thoughts about it in our head. Trauma manifests in the body by creating tension in different body parts. Reliving trauma over and over will only make that tension worse.
By practicing the asana, physical postures and movements, we can work on releasing tension in the body, that results from trauma.
Pranayama, conscious breathing practices, help us to let go of physical tension, also they can help to bring the mind back from reliving trauma, instead focusing the mind on our breath.
Meditation can be difficult to describe. There are many ways to practice meditation. In essence, practicing meditation can heal our minds. It helps us to be more mindful about our lives. As a result our mind is less likely to trap us, by reliving past traumas.
These three practices: asana, pranayama, and meditation, are useful in coming out of a constricted space, sometimes called dukha, thereby reducing suffering.