If you go to a yoga class, the instructor might mention your bandhas, so I thought you might want to know what and where they are.
Bandha is a Sanskrit word meaning "lock," "seal," or "bind." There are three bandhas, and they are basically muscular contractions that help you to breathe, focus on your awareness, keep your body strong, and give you a sense of lightness as you move through postures.
Mula bandha (moola = root; bandha = lock) - the steady contraction & lifting of the perineum (the muscle between your genitals and anus). It's like a Kegel exercise. It's the muscles you'd engage if you were peeing and you wanted to stop mid-stream. As you hold these, you keep the energy and the breath lifting up towards your belly. Holding moolah bandha gives you lightness and lift, and will help you to float through your yoga practice.
Uddiyana bandha [u-Deeyaana = upward-flying; bandha = lock] - the muscular contraction 4 inches below the navel. It's basically like you are pulling your belly button up and in towards your spine. This helps you to bring the breath all the way up into your rib cage, above your navel. As you breathe, you keep your belly still and expand and contract through your chest instead.
Holding these 2 bandhas helps you to perform the Ujayi breath (that audible ocean breath, also called Darth Vader breath) properly. It also gives your core strength and stability. Engaging these muscles also helps to build your internal fire, which helps to warm your whole body, making your muscles more pliable.
Jalandhara bandha (jalun-Dara = throat; bandha = lock) - the contraction where you drop your chin towards your chest. This is supposed to prevent energy from escaping out of the upper body. You don't usually hear about this bandha too much. You only hold this bandha in certain poses.
In an Ashtanga yoga class, you try to hold the first 2 all throughout class. It's really difficult to hold them both for the entire 90 minute class, so I think of these bandhas more as a subtle and energetic lift of energy. It's an awareness of your lower body that keeps the muscles all the way from the base of your spine up into your belly engaged, so that you protect your spine and breath efficiently.
Fit's Tips: It takes time and practice to locate exactly what muscles you are supposed to be engaging, so don't get frustrated when you first start out. I would definitely recommend practicing these bandhas separately, without the poses. Then when you go to class, practice engaging them whenever you remember. Then soon it becomes second-nature, and your body just automatically holds these locks.