The impact of asanas on human body system is expansive and eternal. The muscles, bones, nervous system, respiratory, circulatory and digestive systems of the human body are greatly benefited from regular practice of asanas. All the body systems are coordinated with each other. The body becomes more flexible, and more able to adjust to environmental changes after practicing asanas. The sympathetic and parasympathetic nervous systems are brought into a state of balance with the help of asanas.
On a broader aspect, the human body consists of two central parts called the trunk and the head. Attached to the trunk are the arms or upper extremities and the legs are known as the lower extremities. Bones are the hardest parts of the human body, and form the framework of the physical structure. This framework of bones is called the skeleton that supports the softer parts of the body such as muscles, which are attached to it. It also offers effective protection to some other parts of the human organism. For instance, some of the bones are arranged in such a way that they give protection to the brain, the spinal cord, the heart and the lungs. The skeleton, its joints and muscles are exercised through asanas that leads to the proper development of the bones and strengthens them with the passage of time.
The joints are moved through the full range of motion of the asanas, which encourages mobility and eases pressure. The gentle stretching of the muscles and joints releases muscle tension, thus increasing flexibility. The stretching of the joints in asanas causes the secretion of a lubricant called synovial fluid. This fluid is released into the joints that keep them supple, as well as removing waste products. The result is to reduce stiffness, which will prevent arthritis or improve it if the person already suffers from the condition. Maintaining many of the asanas encourages strength and endurance. Weight bearing asanas usually help prevent osteoporosis, and may also help those who are already diagnosed with osteoporosis, practiced with care, under the supervision of a qualified Yoga teacher. Long term benefits of asanas include reduced back pain and improved posture.
The cardiovascular system of the human body includes the heart and its arteries. Asanas being isometric, they rely on holding muscle tension for a short period of time. This improves cardiovascular fitness and circulation. Many surveys show that regular Yoga practice may help the blood pressure to normalize. As an example, the stomach lift raises the diaphragm, which in turn massages the heart from below. This strengthens the heart muscle, thus resulting in better circulation and less possibility of heart disease.
The digestive system is also known as the alimentary canal that is the system of organs within multicellular organisms that consume food, digests it to extract energy and nutrients, and expels the remaining waste. The major functions of the digestive system are ingestion, digestion, absorption, and defecation. The digestive system is approximately 6.5 meters (20 feet) long and consists of the upper and lower gastrointestinal tracts. The tract may also be divided into foregut, midgut, and hindgut, reflecting the embryological origin of each segment of the tract.
Asanas effect in improved blood circulation and the massaging effect of surrounding muscles speeds up a sluggish digestion. Even if the most nourishing food is consumed, it still has to be digested and assimilated properly and the toxins have to be eliminated efficiently. As the person gets older, the digestive system functions with gradually reducing efficiency. The regular practice of asanas thus results in an improved blood and nerve supply to the digestive and eliminative systems, which in time will get them functioning at peak efficiency. The stomach lifts while asanas massages the digestive organs, as well as contracting and stretching them.
The nervous system in human body is a network of specialized cells that communicate information about an organism’s surroundings and itself. It processes this information and causes reactions in other parts of the body as well. It is made of neurons and other specialized cells called glial cells that help in the function of the neurons. The nervous system is divided broadly into two categories, the peripheral nervous system and the central nervous system. Neurons generate and pass impulses between and within the two systems. The peripheral nervous system is composed of sensory neurons and the neurons that connect them to the nerve cord, spinal cord and brain making up the central nervous system. In response to stimuli, sensory neurons generate and spread signals to the central nervous system, which then conducts signals back to the muscles and glands.
Asanas improve blood circulation, easing of muscle tension and the act of focusing the mind on the breath all combine to ease the nervous system. Long-term benefits include reduced stress and anxiety levels, and increased feelings of calm and wellbeing. Nerves from the brain and spine go to every tissue in the body and therefore the health of every tissue in the body depends upon the fitness of the brain and spine. The headstand causes an increase in circulation to the brain, which stimulates the brain`s nerve cells. This results in amplified vitality and improved brain functioning with increase in intelligence and memory.
Since the nerves from the spine reach to all the organs and glands of the body, a healthy spine obviously plays an important role in vitality and renovation. In fact, the spine is more critical to the well-being than the brain, since the brain is well sheltered by the cranium or skull bone. Where the spinal nerves leave the spine and pass through the intervertebral foramina is a very susceptible area. If a vertebra is slightly incongruous, it may cause the nerve to be pinched in the intervertebral foramina. The spinal nerves do not have guard against automatic damages as the brain does.
The ancient yogis fully understood the susceptibility of the spine and the tendency for slight spinal misalignments to occur. Thus the spine is kept flexible through various kinds of asanas and there would be much less chance of spinal misalignments. Some of the asanas will even correct some minor misalignments of the spine. If the spine and its alignments are not maintained properly, it will deteriorate further and the spinal nerves will be increasingly impinged upon. This state further damages the condition of the organs and glands, until eventually their actual structure becomes unhealthy. This is called organic disease. At this stage, not only is their function impaired but their cells also die. Asanas are instrumental in preventing most of these diseases.
The impact of asanas is also seen to be positive on the human endocrine system as well. The endocrine system is a system of glands that involve the release of extra cellular signaling molecules known as hormones. The endocrine system is active in regulating metabolism, growth, development and puberty, and tissue function and also plays a part in determining mood. Asanas keep the mind calm and at ease. The field of study that deals with disorders of endocrine glands is endocrinology, a branch of the wider field of internal medicine, which has also supported the fact that asanas have great beneficial effects on the particular system. The endocrine system is an information signal system much like the nervous system. The endocrine system mainly uses blood vessels as information channels. Glands located in many regions of the body, release chemical messengers called hormones into the bloodstream specific. Hormones regulate many functions of an organism, including mood, growth and development, tissue function, and metabolism. Asanas regulate and control the secretion of hormones from all glands in the body. Even if one gland is not working, a noticeable loss of health can be experienced.