1) Increases blood flow, lowers respiration rate
2) Slows heart rate
3) Reduces stress, anxiety and aggression
4) Enhances the immune system
5) Harmonizes the endocrine (hormonal) system
6) Relaxes the nervous system
7) Improves brain function and electrical activity
8) Reduces stress and balances hormones to stimulate ovulation
9) Improves learning ability, memory and productivity
10) Improves relationships with others
Mindfulness Meditation by Thich Nhat Hanh
This exercise is very simple, but the power, the result, can be very great. The exercise is simply to identify the in-breath as in-breath and the out-breath as the out-breath. When you breathe in, you know that this is your in-breath. When you breathe out, you are mindful that this is your out-breath.
Just recognize: this is an in-breath, this is an out-breath. Very simple, very easy. In order to recognize your in-breath as in-breath, you have to bring your mind home to yourself. What is recognizing your in-breath is your mind, and the object of your mind-the object of your mindfulness-is the in-breath. Mindfulness is always mindful of something. When you drink your tea mindfully, it's called mindfulness of drinking. When you walk mindfully, it's called mindfulness of walking. And when you breathe mindfully, that is mindfulness of breathing.
So the object of your mindfulness is your breath, and you just focus your attention on it. Breathing in, this is my in-breath. Breathing out, this is my out-breath. When you do that, the mental discourse will stop. You don't think anymore. You don't have to make an effort to stop your thinking; you bring your attention to your in-breath and the mental discourse just stops. That is the miracle of the practice. You don't think of the past anymore. You don't think of the future. You don't think of your projects, because you are focusing your attention, your mindfulness, on your breath.
It gets even better. You can enjoy your in-breath. The practice can be pleasant, joyful. Someone who is dead cannot take any more in-breaths. But you are alive. You are breathing in, and while breathing in, you know that you are alive. The in-breath can be a celebration of the fact that you are alive, so it can be very joyful. When you are joyful and happy, you don't feel that you have to make any effort at all. I am alive; I am breathing in. To be still alive is a miracle. The greatest of all miracles is to be alive, and when you breathe in, you touch that miracle. Therefore, your breathing can be a celebration of life.
An in-breath may take three, four, five seconds, it depends. That's time to be alive, time to enjoy your breath. You don't have to interfere with your breathing. If your in-breath is short, allow it to be short. If your out-breath is long, let it to be long. Don't try to force it. The practice is simple recognition of the in-breath and the out-breath. That is good enough. It will have a powerful effect.
This meditation instruction excerpted from the Shambhala Sun website.