Despite years of research, advances in medicine, and the possibility of a cure for cancer within the next decade, we still don't know the exact function of what we spend one-third of our lives doing: sleeping. National Geographic quotes William Dement, cofounder of the Stanford Sleep Medicine Center, on the mystery of why we sleep: "As far as I know, the only reason we need to sleep that is really, really solid is because we get sleepy." Why we sleep seems to remain a timeless question -- yet we know that sleep is crucial to our well-being, and its quality determines our lives.
Sleep, it seems, is more than just a period of rest. For instance, hibernating animals must actually catch up on sleep after coming out of hibernation, a process known as rebound sleep. Even though they're emerging from a deep state of lowered metabolism, they still need sleep to survive, which suggests that sleep serves a function other than just energy conservation. Another fun fact: Newborn babies spend up to nine hours a day in REM sleep, the stage of the sleep cycle where dreams mostly occur, whereas the average adult spends less than two hours in REM.
How we are affected by sleep is also of particular interest to researchers. There's no question that we feel better after a good night's rest. Proper sleep contributes to psychological health and well-being. However, most of us will encounter sleep disturbances throughout the course of our lives. In fact, one out of three people will experience insomnia at some point in their life.
A mere week of unrest or sleep deprivation can cause severe changes in mood: depression, decreases in emotional regulation, and obvious depletion. It seems that a good night's rest can also enhance the positive feelings and states of being that we cultivate through yoga practice. There's really something to the idea of "sleeping off" difficult experiences.
Something else we know about sleep: Yoga can help improve it. Sleep is a function of the parasympathetic nervous system, the system devoted to rest and digestion. Not surprisingly, sleep onset (the natural oncoming of sleep) and yoga are both associated with an increase in parasympathetic activity. In addition, meditation techniques that don't require intense mental effort or concentration, such as yoga nidra, open-awareness methods, and self-hypnosis, have all been shown to increase parasympathetic dominance.
So can yoga play a role in our sleep patterns? Can it relieve sleep disorders such as insomnia? Research seems to say yes. In one study on yoga and sleep, participants practiced a 45-minute Kundalini Yoga sequence before bedtime that included long, slow breathing and meditation. The results showed statistically significant improvements in sleep efficiency, total sleep time, and how long it took to fall asleep. Another study showed that young adults who practiced Bikram Yoga regularly woke up fewer times in the night, a sign of better sleep quality.
The Charaka Samhita, a foundational Ayurvedic text, states, "Happiness, misery, nourishment, emaciation, strength, weakness, virility, sterility, knowledge, ignorance, life and death -- all these occur depending on proper or improper sleep." It seems that, if we want to live to our full potential, we must approach sleep as a personal practice.
Amanda LoRusso, Kripalu Institute for Extraordinary Living Intern, assists in development, delivery, and research for the IEL's Frontline Providers program. Amanda earned her bachelor of science degree in biology from the University of Bridgeport in 2010. She is a certified yoga teacher and has assisted in a variety of yoga programs. Particularly interested in research, Amanda plans to pursue a doctorate degree in a field linking science to yoga and meditation.
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10 Of The Best Yoga Poses For Sleep
Easy Forward Bend (variation of Sukhasana)(01 of10)
Open Image ModalThe easy forward bend pose is accessible even to beginners, and it's a great one to try before bedtime. If you're tight in the hips, Bielkus advises sitting on top of a pillow to make the pose a bit more relaxing."This one is good for sleep," says Bielkus. "It also eases tension and lets the hips open up, and just creates an overall sense of ease in the body." (credit:Alamy)
Standing Forward Bend (Uttanasana)(02 of10)
Open Image ModalChild's Pose (Balasana) (03 of10)
Open Image ModalThe quintessential resting pose in many yoga classes, child's pose helps to calm the mind and relieve tension in the body. Fold the torso over the legs with the arms extended or by the sides, and rest the forehead on the ground. "Take long deep breaths," Bielkus suggests. "Massage the forehead left to right easing tension at the brow point." (credit:shutterstock)
Plow Pose (Halasana)(04 of10)
Open Image ModalLegs Up The Wall Pose (Viparita Karani)(05 of10)
Open Image ModalThis simple pose, performed against a wall, is excellent for evening relaxation and stress relief. Bielkus recommends staying in the pose for as long as five minutes, with the eyes closed and using a soothing eye pillow if desired. "When we flip the legs up, the blood can rush back down to the heart," says Bielkus. "It has a soothing quality." (credit:Alamy)
Corpse Pose (Savasana) (06 of10)
Open Image ModalGet your body into sleep mode with a simple corpse pose, focusing the attention on the body and breath, and letting go of the day's worries. "By focusing the mind and bringing awareness in, you take the mind off of what is causing stress or restlessness," says Bielkus. (credit:Alamy)
Supine Spinal Twist (Supta Matsyendrasana)(07 of10)
Open Image ModalThis reclining twisted pose can easily be performed in bed before you fall asleep. Lie down on your back and bring the right knee into your chest and then across your left side. Extend the right arm out and gaze to the right, taking several deep breaths and then repeating on the other side. You can also try bringing both legs up and then over to each side, as pictured at left. "Gentle twists relieve tension throughout the whole spine and also aid in digestion and help us rinse out some tension from the day," Bielkus says. (credit:Alamy)
Seated Spinal Twist (Ardha Matsyendrasana)(08 of10)
Open Image ModalLike the supine twist, the seated spinal twist (also known as the half lord of the fishes pose) can create a sense of relaxation in the body while gently stretching the spine. The stretch can be practiced with both legs bent or with one outstretched. (credit:Alamy)
Reclining Butterfly (Supta Baddha Konasana)(09 of10)
Open Image ModalA variation of the basic butterfly pose (pictured at left), the reclining butterfly can help the body get into rest mode. Lie down on your back -- on your bed or on a mat -- and bring the feet together, splaying out the knees in a diamond. If your hips are tight and the pose feels too intense, Bielkus suggests putting a folded blanket or cushion under each of the knees. "Bring one hand to your heart and one hand to your belly," Bielkus says. "Breathe deeply observing the breath move in and out of the body." (credit:Getty)
Left Nostril Breathing (10 of10)
Open Image ModalTo try this relaxing breathing exercise (pranayama), you can either sit up crossed-legged or lie down on your right side. Cover the right nostril with your thumb and extend the fingers out. Then take five to 10 deep breaths out of your left nostril. "If I can't sleep ... As soon as I've done three left nostril breaths, I'm out," says Bielkus. "It's really, really effective." CORRECTION: An earlier version of this article said that the Sanskrit name of left nostril breathing is Surya Bhedana, when Surya Bhedana in fact refers to a different technique. (credit:Alamy)
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