Physiologically this makes a lot of sense as the emotion of anger creates a lot of physical tension as a result of the contractile nature of the stress hormones (such as epinephrine, norepinephrine) and the 'posturing' that we take on as a result of the physical readiness we take on to respond to threats.
A great question to ask yourself when you get a tension headache is; "Is there anger?" and if so "What is the anger?" (Who, what, why etc) and also "Where is the anger?" (Often there will be a place or places within the body that you feel or experience the anger/tension.)
You can then work to release anger by many means. Some of these may include a physical release, such as hitting a boxing bag or having a hard work out.
You may also find value in mindfulness meditation. These can help to gain some perspective and rationality around the anger and allow it to be released and to break the cycle of thinking and worrying about the anger and instead simply allowing it to 'be', and subsequently be released.
Recognising the areas of the body that you feel the tension or anger can also help in the releasing process.
'Breathe into', these areas and on the out breath imagine actively releasing any and all tension in the area.
By releasing physical tension we may inversely release psycho-emotional tension.
Basic mindfulness and meditation techniques can be found in both Choosing You! and Time Rich Cash Optional.
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