The battle against those tensions of yours by controlling your respiration.

You can control the tensions via respiration.

I have already discussed relaxation, yawning and stretching and if you have done the exercises I stated earlier you should notice improvements in tension relief. Let us now go a step farther. The next thing you need to do is learn to control your breathing. Yoga breathing, at its best, employs five ideas:
Using your lungs to their whole capacity. Retention of the breath. Cleansing of the lungs and bronchial passages.
Breath slowly and then start stretching.
Alternate breathing, or breathing through one nostril at a time. It is called "Sun and Moon" breathing.
We will discuss the five different fundamentals underlying Yoga breathing techniques.
Firstly, then, practise the Yoga Complete Breath as often as you can and always remember that the depth and quality of your breathing is far more important than the number of breaths you take.
It is a good idea to start your Pranayama or breathing exercises by taking a few full breaths to cleanse your lungs and prepare yourself for the other breathing exercises, all of which are basically variations of the Complete Breath. Practise the Complete Breath in any position you prefer, either lying down, sitting on the floor with your spine straight, sitting on a hard chair with your hands in your lap, or standing up straight.
Retention of the Breath
This should not be attempted until you are able to perform the Complete Breath at least half a dozen times in succession without experiencing any unpleasant dizziness or fainting. Then proceed as follows. Breath in deeply and hold the breath for a couple of seconds before exhaling. One second is enough at first, but gradually extend this period of retention until you can hold your breath for several seconds without discomfort and without employing any force. Take it easy and feel into your lungs. Do not try to force them to do something that they are clearly trying to tell you is uncomfortable. Remember that correct Yoga breathing is based on the body's natural impulses. When you are breathing out, you will have an automatic pause while your lungs gets all the air out. At first you must obey this natural impulse and breathe in when you feel the need to, but gradually extend this pause for a second longer, and then yet another second, but do not force the pace.
The following deep breath is more full and deep because the pause is gradually becoming extended. Practise retention of the breath until you can perform it to your satisfaction but I repeat s-l-o-w is the word for Yoga breathing, slow and rhythmic. You should never practice this in a hurry.