Tension is one of the most common blockages to practice and mindfulness that we encounter. Whether it appears as anxiety, frustration, anger, expectation or sadness, most of us carry around a lot of tension. Perhaps we find moments of peace and relaxation (and therefore concentration and open mindedness) when we meditate - for some of us maybe not even then! When the body and mind are tense, it is much harder to practice in all areas - patience, mindfulness, kindness - all of the practices and perfections become harder when we are not relaxed.
Master Guo Gu recommends progressive bodily relaxation, as well as grounding oneself in the body. If we are exceedingly anxious, we can use breath counting or meditate on sound as a way to bring down the heart rate and refocus the mind in the here and now.
When the body and mind are relaxed, they can focus, open and also let go of arisings. The mind can become like a gentle clear brook, rather than a raging river which sweeps up everything in its path.