Impact Of Gravity On Bodily Fluid Flow: The Great Debate

The Impacts Of Gravity On Blood And Lymph Flow

Discuss About The Great Is Gravity Impact On Bodily Fluid Flow.

Gravity is a force, which makes object move towards the center of the earth, this force was discovered by a great scientist, Sir Isaac Newton. This force explain why when one throws an object up in the air it will come down to the ground as opposed to continuing with the motion up the air or moves to the other directions. This force will actually affect the flow of the body fluid when it is in excess. If the gravity is capable to prevent the flow of water uphill, then it can as well change the direction of blood and other body fluids flowing in our body.  Over a period of time the gravity will take a toll on the circulatory system and this may cause varicose vein which will in turn decrease the rate of blood circulation and leads to the swollen limbs.

 If there is a poor circulation of body fluid to the ear, skin, scalp, eye and brain then this is the key reason why our most valuable organs deteriorate over a period of time.  A simple experiment may be tried to witness the powerful effect of the gravity on the circulation of the body fluids and blood:  lift left hand for about three minutes, then lower that arm and then compare it with the other right hand. Which limb will be pinker?  Then consider standing the whole day with your lower limbs (Atilla 142). Our bodies subconsciously fathom that individuals require the circulation to our heart from our limbs.  

How frequently will one finds himself or herself propping up his/ her legs on an ottoman or a desk?  In most cases we may consider all these problems as unescapable effect of aging but the reality of the matter is that all these are merely due to the constant force of gravity and this can be avoided. Another evidence is that an astronaut can grow at a rate of two inches while in space during the times he is in orbit (Keane Mehrabian 141). The astronaut’s discs will continuously absorb vapors from the blood stream.  But when there is less or no gravitational pull to squash the vapor out from the disc it will remain plump hence their spines will remain relatively longer and the astronaut taller.

 In actual fact, space suits are made to provide accommodations for the extra two inches spinal stretch that result in the astronaut. Regrettably, many of us will always remain on earth for our whole lives. Therefore, the following are some ways we can compensate for our earth bound lives.  

1. As grownups, we support our feet and legs on stools or desks to compensate for the constant presence of the gravity.
2. As fetuses, we all advance in the almost weightless surroundings of wombs in our mother whereby during the end, we essentially turn to enable the development of our brain.

• As children, we love to "escape from gravity" by riding the swings or hanging upside down on the monkey bars.

1. As infants, we often slept bottoms-up! Keeping our heads lower than our hearts, we encouraged a proper supply of blood and oxygen to our brain.

Impact of Gravity on the Lymph flow

It is not possible to escape gravity, but we can attempt to trick it to make it work in our favor. How?  Through reversing the position of our body under its influencing force. Employ gravity to stretch and elongate your body (Scholle 243). The Nachemson study indicated that it is impossible to escape compression even through lying down. The same study shows that this compression can be overwhelmed through using traction of about sixty percent of our body weight. Mechanical traction can be as well uncomfortable and complex to be employed and to practice at home (Turner 120). The flow of blood to all parts of the body is mainly controlled by blood pressure. The blood pressure of arteries always outweighs gravitational fluid pressure.

When one arise, the difference in pressure between his/her heart (reference level) and his/her feet in the veins is merely the pressure as a result of a column of blood approximately 1000mm tall. That's roughly equal level as 70mmHg. For contrast, individual's blood at stationary systolic pressure is approximately 130mmHg. When a person the is upright, obtaining body fluid in his/her upper parts of the body such as brain from the heart will require a systolic of approximately 50mmHg?. In another version, even when the individual stands on his/her head, his/her heart can obtain blood to all his/her extremities (Ingham 121).

The return of blood/body fluid is partly by gravity from the upper body and it is also partly by pressure (arterial pressure is higher than venous pressure but is measurable).The lower body has the opposite problem - gravity is trying to pull venous blood back down, and this pull (while you are standing) is higher than venous pressure (Huppert 120). The deep veins of the lower limb contain a structural feature that permits the muscles of the legs to operate as a pump since they have valves which prevent back flow of body fluid.

 During the contraction of an individual’s leg muscles, the body fluid/ blood will squeeze the adjacent veins. Blood/body fluid can then flow only in the direction which the valves will permit which is going towards the heart (Taylor 78). During the relaxation of the muscles, the veins will be filled with the body fluid/ blood from the capillaries (David Wolf 321). If an individual is sitting or standing for a quite long period of time, for instance, during a long distance journey, this muscular squeezing will not transpire and the individual may find out that his/ her feet swells as fluid come out of vessels into the interstitial space (Sedov 231). Shallow veins in the arms are as well contain valves but these have their own flow through being squeezed, nevertheless if an individual lowers and raises his/her arm , the gravity will make the blood/ body fluid out of the individual’s  arm if he/she raises it. For the a better analysis of the how great is the gravity's impact is on bodily fluid flow, it is best discussed in the below sub topics;   

 Blood flow in our body is basically affected by the force of gravity (McFarlane 421). Shallow veins in the arms are as well contain valve but these have their own not through being squeezed, nevertheless if an individual lowers and raises his/her  arm , the gravity will make the blood/ body fluid out of the individual’s  arm if he/she raises it. The presence of gravity may reduce or increase the rate of flow of both blood and lymph.

 The lymphatic system is basically a sprout in the cardiac system and it is composed of lymph nodes, lymphatic vessels, lymphocytes (which are immune cells) and lymph. Lymphatics were discovered first by Hippocrates long time ago in 400BC as vessels having white blood but since that year the lymphatic system was not accurately described up to the 1600s when William Harvey published his detailed description of the lymph and blood circulatory system. The flow of the lymph is as well manipulated by the force of the gravity (Aaslid 531). The flow of the lymph will be low where the force of gravity is lower, for instance, the flow of the lymph will be relatively lower in an individual who is on the moon where the force of gravity is about 1.66. While for an individual who is on earth where the force of gravity is about 9.81, the flow of the lymph will be comparatively higher.

 Lymphatic system performs a very significant role in body fluid regulation, homeostasis and lipid macromolecule absorption immune function (Ranel 123).  All these functions require the flow of the lymph therefore to achieve these roles, lymphatic’s have to move fluid and its contents which includes the chylomicraons, immune cells and macromolecules from the interstitium via the lymphatics across the nodes, and into the great veins of the blood circulatory system (Beneken 441). Therefore as aforementioned when an individual is in a region with a relatively lower force of gravity then the flow of these contents of the lymphatic system will be relatively lower and this may affect the health of an individual since the immune is not fully distributed equally to the rest other parts of the body. This effect is illustrated in the figure below

The body of any individual should impart energy to the lymph through pumping technology to drive it along the network of lymphatic and employ valves and muscle pumps to produce lymph flow as well as preventing its backflow (Boyle Bullock 421). The lymphatic system employs both extrinsic pumps that depend on the cyclical expansion and compression of lymphatics by nearby tissue forces and intrinsic pumps that depend on the intrinsic rapid retrenchments of lymphatic muscle.  The lower gravity on the body may results in two major conditions in regards to the normal flow of the lymph, these conditions are known as oedema and lymphedema.

 This is a condition where individual's swelling occurs in a specific body part but in some cases, it may be more general depending on the cause. It is mainly caused by having excess fluid in an individual's body tissues. Basically, this condition is characterized by the accumulation of the fluid in the skin resulting in swelling mostly in the lower ankles and legs due to poor flow of the lymph. In many cases, oedema is witnessed when an individual stands for long periods          during a long journey or a flight (Danielsen 321). This condition may result in thrombophlebitis or varicose veins of the deep veins in the legs cause oedema that is localized to the legs (Caiozzo, 310). Parts of the body with noticeable oedema include hands, arms, feet, ankles and mostly legs.

The main cause is when the tiny blood vessels in the body or capillaries tend to leak fluid. Swelling thus occurs when the fluids build up in the tissues that are in the surrounding.

• Being in one constant position for quite too long, like in a situation when travelling long distances.
• The continuous intake of food that has too much concentration of salt
• Pregnancy
• Experiencing premenstrual signs or symptoms

• When the skin retains a pit or dimple when it has been pressed for several seconds
• Puffiness/ swelling of the tissue that is directly under the skin. This normally occurs, especially in the legs or arms (Daniel 431).
• Having an increased abdominal size.

This condition is a long-term condition and it leads to swelling in the tissues of the body. Excess fluid is collected in the tissues which tend to result in swelling of affected part of the body. Lymphedema more usually affects one of the legs or one of the arms but in more severe cases, it would affect both the legs and both the arms (Antonutto 391). In other cases, it impacts on any other part of the body (Di Prampero 405). The individual’s condition will worsen when the lymphatic system does not operate effectively, since lymphatic system is a setup of glands and channels all over the body which enables removal of excess fluid and fighting against infection in the body.  It is worth noting that lymphedema is treatable and should be identified as soon as possible. If this condition is not treated it can become worse (Shim 121).

The key sign of this condition is swelling in all parts of an individual’s body.  When an individual is in this condition it will be very hard for him/her to fit into his usual clothes, watches and jewellery as he/she will feel a tightness.

Initially, the swelling on the individual may appear and disappear but in some case, it may get worse during the day and reduce at night.

1. fluid leaking through the skin
2. an aching, heavy feeling

• wart-like growths developing on the skin

1. difficulty with movement
2. repeated skin infections
3. hard, tight skin

• folds developing in the skin

It is believed that primary lymphedema is the first condition while the secondary lymphedema may result from other diseases such as surgery of cancer, other cardiovascular diseases e.g. varicose veins and ulcers, injury to the body or trauma, and from inflammatory conditions e.g. rheumatoid arthritis.

Maintaining a healthy lifestyle which includes a well-balanced diet, proper exercise and movement should help reduce the buildup of fluid and as well stimulate a good flow of lymph. Putting that into practice should help reduce the chances of acquiring these infections and even its severity if already affected like in the case of lymphedema which may be difficult to treat hence the need for better control.

These two conditions aforementioned are high contributors due to the inability of the blood and lymph to flow in the whole human body. And in most cases, this is witnessed when an individual stand for so long (Kappel 211). Therefore there will be difficulties in the flow of the lymph. Lymph will face difficulty to flow against the force of gravity from the legs to other parts of the body when an individual starts for a very long period of time (Kappel 112).

 The effect of the force of gravity on the flow of blood is a concern of significance. Surgeon and physicians periodically observe the orientation and position of the body upon the sound of the heart, pulse rate, disease on the heart and lungs, pneumonia, varicocele, varicose vein, syncope (Batzel 277). These conditions alongside the conditions like haemorrhage, chloroform poisoning, anaemia and shock are all viewed to be greatly influenced by the orientation and position of the body. Some scientists like French physician Piorry indicated that if the force of gravity is made to aid the heart in the pumping of the blood to the brain then the syncope will cease (Kaufmann 109).  

And for this effect of gravity on the flow of blood is why in most cases when a patient is unconscious and requires a first aid he/she is made to lie horizontally to enable the blood to flow to all parts of his body (Landau 90 ).  Piorry further carried an investigation to clearly analyze the problem by using dogs to carry out his experiment. In his experiment, the French scientist placed these dogs in feet down head on top vertical orientation. After that he bled the dogs from the  jugular vein, for the period of time required until they developed a syncope. Through putting the dogs in the feet down head on top vertical orientation, the dogs at once restored to consciousness. He got the same result for every time he repeated the same experiment but alternated the position of the dogs.

From his results, Piorry then concluded that this was as a result of the effect of the force of gravity on the flow of the blood. It was the force of the gravity that when the forelimbs of the dogs were held down, the veins got swollen and the capillaries got filled up with the blood. And the reverse also occurred when the forelimbs were held up – the varicoceles got enlarged when the animal is made to stand and then diminishing in the horizontal orientation and that the face and the head redden when the animals are held down. It is because of the influence of the force of gravity that makes an individual to suffer from pneumonia the posterior border of the lungs if the patient is made to lie on his/ her back.

And for the influence of the force of gravity when the patient is made to lie for a length of time on his/ her face then pneumonia will appear in the anterior lungs border.  After all these experiments, the scientist then deduced that the force of gravity has a highly marked effect on the blood circulation. And this is vividly observed in most patients who are always weakened by any cause. Piorry also affirmed that the effect of altering the position of the patient will determine the diagnosis of apoplexy and syncope (Gagnon 231). Therefore these effects of the gravity on the flow of blood are analyzed through the consideration of the position of the patients or any other animal employed for the experiment (for instance as Piorry used dogs).

 The state of weightlessness is a condition where there is no force of gravity acting on a body, this can be due to the force being locally weak or in some cases it can be due to both the body and its surroundings are and freely accelerating under the force (Kennedy 310).  This condition has an effect on the flow of the blood and the lymph in our body.  The effector changes are significant and observable to the circulatory system when one is in a state of zero gravity or lack of gravitational acceleration. These effects are either short term or long term adaptations. Some of the serious effects of the weightlessness to the flow of blood and lymph include redistribution of fluids and loss of bone and muscle mass in our body (Novak 410). After a period of time, the effects of zero gravity may find the middle ground to the astronaut concert that may increase the peril of them being hurt and reduce their ability to absorb oxygen also thus may slow down their cardiovascular circulation.

The state of zero gravity on the body may cause the removal of hydrostatic gradients. This further brings a shift in thoracic fluid (Melchior 211). When microgravity arrives, close to two litres of fluid will move from the lower part of the body to the upper part of the chest and head. When this happens, the neck and the face may swell with the veins of the neck protruding while the legs get skinnier (Scrinivasen 231) . As time goes by, the body tends to adapt and the distribution of fluid becomes uniform. The pressure of the artery equalizes all through the body hence it directly right atrial pressure. Whenever there is increased fluid in the head, it always results in a nasal congestion, pressure on the eyes which to some extent can lead to changing the eyesight prescription, and causing headaches (Neumann 761). Our bodies have mechanisms that monitor several variables and their corresponding adjust processes whenever the given variables are altered. Adjusting how blood is pumped all through the body based on the pressure readings are done by the baroreceptors. Whenever there is an increased fluid volume in the chest, it will result in a decrease in anti-diuretic hormone and thus the release of aldosterone which will result in an increase in the production of urine and subsequent decrease in thirst (Njemanze 23). This will help stabilize the pressure and reinstate normal flow.

 Body fluids including the blood and the lymph make about sixty percent of our body weight and is highly influenced by the effect of the force of gravity.  Therefore when this force is absent, there is a higher probability of these fluids to accumulate at the lower side of the body but by the way of evolution, there is a possibility of evolving a system which balances the flow of blood to the brain and heart whilst the individual stands (Noordergraaf 65). These systems may endure to work even in a zero gravity, thus making the fluid to accumulate at the top of the body.  And it is for this reason why astronauts always have swollen faces. Accrual of fluid in the faces like eye may also impair the vision of the astronauts for some days till the brain will learn to compensate and rectify the image visualized by the astronauts.  

The change in fluid distribution is can be reflected in difficulties in the body’s balance and a loss of the sense of smell and taste (Henry 871). More significantly, this initiates a series of universal effects made to familiarize the body to the novel new environment, nevertheless, these have a hazardous impact upon the return to Earth. The occurrence stems in part from variation in the blood pressure regulation by the autonomic nervous system and the loss of about 20 percent of the volume of blood fluid since in this conditions of microgravity is unnecessary for systems to keep blood pressure constant as blood and lymph spread further all over the human body. A weaker heart muscle makes a reduction in blood pressure and this will hamper the flow of oxygen to the brain and other upper part of the body (James 431).

Lymphatic system will be affected by lack of gravity since this system requires the gravity to be able to performs a very significant role in body fluid regulation and homeostasis (Goldbeger 76).  Thus these roles require a flow of the lymph to enable overall bodily fluid movement and its contents which includes the chylomicraons, immune cells and macromolecules from the interstitium via the lymphatics across the nodes, and into the great veins of the blood circulatory system. Therefore when an individual is in a region without the force of gravity, then the flow of  the constituants of the lymphatic system will be affected and this may affect the health of an individual since the immune is not equally distributed to the best part of the body (Nadim 121). And in most cases with the lack of gravity, these fluid of the lymphatic system may be seen accumulated in the lower part of the body.

There are key noticeable variations in the flow of the blood in the absence of gravitational acceleration. Studies done recently indicate that there is no concern that the variations threaten the activity and health of the astronaut as long as activities are performed in a controlled environment.

Lack of the force of gravity which results to weightlessness on the body, leads to an elimination of gradients of hydrostatic (Olufsen 231).  This will lead to a fluid shift ta to the thorax on the onset of the microgravity. Around three litres of fluid of the body will definitely shift to the head and chest from the lower body.  The astronauts pronounce this as the bird-legs and puffy-face effects (where the neck and the face will swell). The veins around the neck will protrude while the legs become skinnier. After a certain period of sometimes time, the body adjusts to some extent and the distribution of the fluid gets even. Arterial pressure will balance all over the body and hence reflects right atrial pressure directly. With more fluid in the head time and again leads to headaches, pressure and nasal congestion on the eyes which may change the prescription eyesight of the astronaut (Thomas 98).
Human's bodies are somehow complex mechanism which controls so many variables and regulates practices if these variables are changed. A larger volume of the body fluid in the chest will as well leads to a reduction in ADH and aldosterone hormone that leads to an increased production of urine and a reduction in thirst. The muscle of the heart does not operate as hard in space (Yoshimoto 541). After some period of time, blood volume decrease, the heart shrink and there is a reduction in blood pressure.
Nevertheless, exercise has been highlighted to counter this deterioration - especially, propelling appears to be more prevalent.  Research from this condition observed in astronauts has assisted doctors to detect the roles played by gravity in illnesses like Postural Orthostatic Tachycardia Syndrome (James 76). The blood will change within a period of the first one week. Astronauts have characteristically lost around ten percent of the red blood cell mass since the swing of blood to the chest from the legs will trick the body to the rationale that it has much blood.  This will lead to the kidneys in producing little erythropoietin which further leads to few red blood cells prepared in the bone marrow (Panerai 213). After a long duration of flight or journey, it will take some period of time for the circulation of the blood to restabilize and for the circulatory system to readapt.  About 80% of astronauts experience low blood pressure after their return, with symptoms like tunnel vision and cold sweats (Panerai 433).

Spending long periods of time in zero gravity (e.g. in space) leads to hearts becoming more spherical and losing mass. This condition could lead to cardiac problems. A recent study carried out on some astronauts support that statement.  In the study, images of the astronaut’s hearts were taken using the ultrasound machine from the international space station. Images were taken before, during and after the whole period of time the astronauts spent in space. The images did reveal that the heart takes a 9.4 percent spherical increase when in space (Rideout 222). This spherical shape may mean that the heart is not functioning very efficiently. However, the condition seems to be temporary given the astronaut's heart got went back to a the normal elongated shape from this spherical shape after they had returned to earth (Picot 321).

Female and male react differently when they are exposed to zero gravity for a long duration of time, and these differing results have health concerns.  For the last few years, six group sworking with National Space Biomedical Research Institute and NASA have keenly analyzed how the health for both the male and female astronauts is affected by a long-term flight especially a space flight (Smith 329).  

In expectation of forthcoming space flights for a long duration of time, the research will probably provide perceptions into consideration for safety and health of the astronauts, with specific attention put on how these will affect male and female differently (Tiecks 712). These differences are basically analyzed based on the nature of both sexes as well as how their exposure to the zero gravity will affect their health.  

For instance, the researchers found that females will always experience less hearing loss in at their late age, as a health effect which occurs on Earth and do not show any important sign of vision losses after exposure to zero gravity, as in space (Ursino 110). But men will experience more shortfalls in each of these environments. This variation can be taken into account as planners organize a mission for the unique physiological response of both female and male astronaut.  Some of the main physiological difference between the female and the males are highlighted below.

In females, they display orthostatic intolerance (the ability to stand for a long time without fainting) which is more prevalent on returning from space while in males, they will not have this ability.  And as for vision issues, about 82% of the male astronauts from space had serious vision impairments as compared to 62% of the female astronauts from space (Wyclif 510). After exposure to zero gravity for a long period of time, female astronauts experienced a higher incidence of space motion complications as compared to their counterpart males. But on return to earth from space, many men showed multiple symptoms of motion sickness compared to the women.  Most scientists are quick in noting that in terms of psychological responses to the flight in the space (Warner 131).

Luckily enough, the International Space Station has for many years provided a platform to partake in these types of research to provide us with valuable biological information for a long period of time now regarding the extended stays in space on both female and male astronauts (Rose 720). In the year 2011, there was a report from a National Academy of Science that accentuated the requirements to scrutinize the influences that gender has on the physiological changes occurring on their bodies.

A chief deliberation in a personalized medicine is the crew members’ gender. Even though in the current years the definitions have been more nuanced in the clinical community. On earth, key components of our bodies are basically prejudiced by gender factors (Krul 300). The groups of researchers observed the disparity in the information between females and males of the spaceflight crew who have travelled to space (Tornado 410). In many publications, several differences were found of which are highlighted below;

Female always experience more blood plasma volume loss as compared to male during spaceflight. A female’s stress response typically comprises an increase in heart rate whilst male’s stress respond to is an increase in vascular resistance (Oscar 211). In terms of motionless, more studies in space are needed to accumulate a full set of data.  Females are capable to stand for the long duration of time without fainting as compared to the male. This is an effect of the force of gravity and known as orthostatic intolerance. A significant reason for this gender difference in the latter is the reduced leg vascular compliance which is more in females as compared to males.      

A variation in the operation and concentration of the most significant constituents of the immune system linked to the space flight have been documented. However, variations between female and male immune responses have not been fully scrutinized in space (Kane 290).  But on earth, female have a more potent immune response as compared to male, which make them more resistant to bacterial and viral contagions. But once infected, female will produce a stronger response leaving them very sick. Such responses will make the females more vulnerable to autoimmune infections.

Radiation available is a key peril for travel in space. From studies, it has been documented that women are more vulnerable to radiation-induced cancer which are as compared to their men counterparts, therefore permissible exposure to varying radiation intensities are higher for men than women astronauts (Dickens 300).

Shifting to zero gravity after arriving to the International Space Station, women astronauts testified a relatively higher occurrence of space motion sickness (SMS) than in men. Contrariwise, most male will always experience symptoms of motion sickness upon arrival to the earth (Paul 760). For hearing sensitivity, if checked at difference frequencies, the deteriorations taking in consideration is more hastily in male astronauts as compared to female astronauts. But there is no clear evidence which proposes that the gender-based hearing alterations in the astronaut population are linked to exposure of zero gravity (Bill 301).

A musculoskeletal reaction to gravity was more variable in humans and a gender-based variance was not witnessed (Kariri 398). The infections of the urinary tract in the space were more common in female as compared to their counterpart males but all these infections were treatable using the antibiotics.  

One of the important key effects of the gravity on relating to medicine is the formation of the varicose vein in the legs, venous blood travels against the force of gravity as it travels back towards the heart. The force of gravity on the skeleton contributes in many ways to healthy bones.  If a person becomes weightless like an orbiting satellite in space, she or he will loses some bone mineral. This might become a severe problem on those very long journeys in space. Likewise a long-term bed rest, eliminates much of the force of the body weight from the bones which lead to serious bone constitution loss.

Thus with a reduction in the force of gravity by a significant quantity, as for example during a prolonged bed rest and a space flight in the space, effects on the skeleton normally arise rapidly and profoundly. A case of study of extended bed rest looked at in accurately determining the effects of limited or absence of gravity on BMD (bone mineral density), experienced decrease in femoral neck and lumbar spine regions (Rutt 521). Since movements result from the impacts of forces of gravity and the forces by muscles, reductions in both types of loading will result in atrophy and is readily seen in both in the bed resting state and in the weightlessness state in space visits.

 With marked muscles forces reductions, significant muscle wasting is witnessed. Implementing of measures which counter these effects have been selectively effective in minimizing the loss of muscles and bones during the two to four months period of bed rest. An example involves conducting exercises of resistance relating to lower and upper parts of the body. This was done using a horizontal machine of exercise and proved was effective to preserve the muscle mass and the BMD for a good number of body regions. With the same concept, exercises for pine endurance and lower extremities resistance were done using an upright stationed treadmill in the chamber of lower body negative pressure deteriorated .There was weakening of the lower extremities although it did not prevent BMD. There was a hip decline despite the preservation of the quadriceps muscles mass and an increase in the strength.

Infectivity towards preventing either cortical trabecular bone loss was also witnessed at the international space station exercise countermeasures. In relation to the outcomes and findings from the bed rest and studies of flights into space revealed that in regions or environments bearing lots loss of weight on the skeleton minus any effective exercises, it is somehow complicated and challenging to preserve BMD and elaborate outlines are needed to show the significant roles performed by the force of gravity in maintaining of skeletal integrity together with its mass.

Human brains have evolved and developed towards efficient functioning in the earth’s gravity. Several experiments conducted in the international space station depicts that human brains possess an internal model or concept of how the gravitational force works. This is the force that scientists and researchers normally apply in predicting the position of a ball when it is moved or caught while moving. In environments lacking weight, a ball moves in uniform or constant speed rather than constant acceleration and hence human reactions are normally slightly off. The same force of gravity similarly influences the flow of blood in and out of the brain or through it. Brains electrical activity is highly affected by accelerations exceeding five grams resulting to in the production of patterns resembling epileptic seizures.

When one intends grasp something, the brain usually gets ready earlier in preparation for the catch. Movements of the hands are then directed from by the brain. In less than a tenth of a second, the commands o from the brain to the hands are always received by the latter. The less than a tenth-second delay is often a requirement allowed by the brain in order to predict arrival time of the ball. This process is normally rendered complicated and complex as a result of the gravitational force that frequently makes the soaring ball speed vary or change. This phenomenon is normally achieved by the brain through the following concepts:

 In relation to Joe McIntyre, a neuroscientist at De France College, possession of an internal model of gravity by the brain facilitates or makes it very accurate. He further continues to suggest that the brain has got the capability to anticipate, calculate and eventually naturally performs a mechanism to compensate for the acceleration brought by force of gravity.  

The neuroscientist conducted an experiment and from the experiment, he derived his conclusions. The experiment was a ball catching experiment which was performed in space. The astronauts who participated caught balls which got released from a spring-loaded cannon. Unlike the situation on the earth, the balls moved with a constant and uniform speed but not constant acceleration as it would be experienced in case the experiment was conducted on earth. Motions of the astronaut's hands and arms were tracked through the use of cameras of infrared and electrical activities and efficiencies of their hands were measured and estimated by use of electrodes as the astronauts played the catch game.

The McIntyre experiment involved flying to the space for a duration of seventeen days in the year 1998 and he derived lots of science life lessons relating to the following. As the astronauts were flying to the space, they were in a position to catch the ball although they were somehow a little bit poor in with their timing. They tended to behave or react in a manner that suggested they were expecting the ball to be moving in a speed that was faster than it physically moved or in simple terms, in a way that the force of gravity of the earth was at its normal.

The same gravity force expectation from the astronauts was evidently ongoing as the astronauts persistently kept miss-anticipating the motion of the ball for about 15 days while conducting the experiment. It was witnessed thereafter that they began to adapt to this absence of gravitational pull. The point of concern was to the reason why the astronauts kept on anticipating gravitational force or impact.

A change in acceleration is normally well sensed by the astronauts who orbit the earth. For example the astronauts say when they start floating and then they have to continuously adapt to the weightlessness. This is done in a number of ways. After a period of about two to three days in space, motion sickness tends to normally disappear. For about a duration of 15 days, the astronaut’s brains experienced a consistent prediction that the balls would experience a similar acceleration as witnessed on earth even in the presence of conflicting evidence. The non-flexible mentality or behaviour is in full support of the idea and notion that the human brain is in possession of a built-in gravity model resembling a unique computer behaviour in the human head of calculating acceleration.

The neuro lab experiment of catching the ball had an aim of finding out or proving the newton’s motion equations contained in the brain of the human beings and it realized the reality and truth in it. This is further confirmed to be the reality under the hyper-physics concepts of speed, acceleration, and force of gravity.

Some other evidence were revealed by McIntyre in his study. These evidence included the following: a baby is positioned safely on a glass table in a way that he or she can see the floor underneath. It's As the baby realizes this, it suddenly develops fear. The fear develops in the baby as a result of belief of falling yet this baby lacks any previous experience of falling. This response does not require much to be elicited and it translate to a very significant and big hence a conclusion that a downward acceleration is expected.

Finally, the normally anticipated acceleration has a possibility of being changed to other values from the commonly norm on earth. In relation to the previous experiment, after the fifteenth day of the astronaut’s experiment of catching the ball, the ball was now being caught by the astronauts on the shuttle in a better manner compared to the previous occasions. The arm movements remained consistent as during the previous early days of the experiment though it grew smaller in amplitude. In addition, additional movements were witnessed to be added by the astronauts on the arms which occurred just a very short while before the impacts of the ball.

The researcher, McIntyre looked surprised with the speed at which the ball dropped when a similar experiment was repeated by the astronauts on the ground. It was concluded that the astronauts had adopted to 0-g and then later was readapted to 1-g. Nevertheless, there existed a possibility that various models of acceleration were learnt and retained by the human brain. In most distinct concepts and scenarios, the brain decided on which one it had to apply. That was the conclusion made by the researchers in explaining the outcomes.

In many significant aspects and concepts, the nervous system and the brain of human beings formed a puzzle. The safety of the experiment was facilitated through the mutual understanding by the astronauts on the self-adjustment mechanism to the movements of objects that were not expected in the space. Those on earth also achieved some benefits, a portion of them being that the experiment offered a unique way of exploring and utilizing the nervous system. A good number of brain damages and sickness affect the normality in timing mechanism of the brain just like it was experienced by the astronauts. This revealed how the work functioning of the brain and the nervous system, forms a significant grounds and methods or steps in finding a cure for the mentioned challenges or problems of the brain.

Sir Isaac Newton commenced understanding the roles played by the force of gravity in controlling and regulating the orbit of the moon during the event that an apple suddenly fell on his head and he immediately formulated the gravitational law. Despite this experience, Isaac Newton assumingly did not come to the knowledge of the effects and impacts of the force of gravity on the organs of the human body. Applying the concept that if the flow of water uphill can be highly prevented by the gravitational force then similarly blood in human bodies can also be stopped or prevented from flowing to the upper body parts. The force of gravity is thus negative. Eventually, it was clearly evident that gravity had lots of effects on the blood circulatory system and gave rise to concerns; it could easily result in blood circulation disorders such as:

1. Varicose veins
2. Swelling of the limbs
3. The decrease in scalp circulation

• Insufficient blood flow or circulation to important body organs such as eyes, ears, scalp, brain and skin.

Lots of factors exist that influences the heart rate. Illness, posture, stress, exercise, eating habits, breathing and medication might all lead to speeding up or slowing down of the heart rate. Most people do not normally tend to think or be concerned with variations in their heart rates. The concern only develops whenever the variations become of a higher magnitude in relation to the observable or experienced impacts on the person. Gravity subject human’s various parts to constant downward pull. Collectively, shoulders, chests, organs, backs, feet and legs are also subjected to the effects of this force. The common pain in the feet and legs are frequent experiences with most people mostly after standing upright for a long duration of time.  Gravity tends to be consistent, persistent and never discriminates.  As long as an organism is on the planet earth, old or young, athletes or couch potatoes, all organisms or bodies suffers or enjoys the observable effects of the force of gravity.

A body posture in the upright position is held in opposition to the force of gravity while either standing, sitting or even lying down laterally. A heart rate is the quantitative measure of the frequency in counts of number of times a person's heart contracts or beats in the duration of a minute (Brown 321). In consideration of the above descriptions or definitions, it is observable that posture highly influences or affects the heart rate of a person. When standing in an upright position, the heart rate increases to a significant level whereas lying down results to in a decrease in the heart rate.

In addition, chronic diseases relating to postural habits and poor slumping habits may also lead to increased heart rates (Booth 34). Eventually, it is worth concluding that the force of gravity also affects the heart rate significantly as gravity does not engage in the pulling of blood flow above the heart of a person. Flexibility and the strength of muscles used in achieving a certain posture also have significant impacts on the heart rate. Normal breathing too also should be obtained through the balancing of the upper backs and chest area. Faster pumping of the heart is normally facilitated by shallow breathing with the aim of receiving enough amounts of oxygenated blood to be distributed to all parts of the body (Convertino 322). This is thus avoided through the balancing of the chest and the back area.

The hearts of the astronauts became very spherical and took a decrease in muscle mass during their expenditure of time in space for a longer duration of time. This lead to a fear of suffering from potential cardiac problems. The health of the astronauts deteriorated as a result of variations in the physiological conditions as they conducted a mission to the planet Mars and in space.

Astronauts who have been on various missions into space have reported that they did suffer from balance issues and to some extent did experience illusions that are perceptual when they were in microgravity whenever onboard the international space station. A research carried out by a team of researchers led by Rachael D. Seidler was to conduct brain imaging assessments as well as behavioural valuations on a number of astronauts (Edgerton 422). The astronauts were asked to finish obstacle courses while being timed as well as examine their ability to identify and manipulate a 3-dimensional object mentally before the space missions and after they were back on earth.

The same examination was also performed when the astronauts were on board the international space station. The brains of the astronauts were studied using the structural and functional magnetic resonance imaging before and after the space mission hence the researchers were able to define the link between physical changes in the brains of the astronauts and also in their behavior. The illusions that are perceptual which are witnessed by the astronauts are as a result of a lack of gravity. At some point, it leads to struggle in directing the eyes and head movement.

The loss of muscle mass was caused by the heart not working as hard as it would of in on the presence of the gravitational of force of gravity on the earth. As suggested by studies and observations made by Thomas James, cardiovascular imaging and lead scientist for the ultrasound at NASA, he expected the astronauts to experience a lot of problems and challenges on upon their immediate return to earth. He further looked into measures that could be adopted with an aim of countering the expected effects and challenges (Perry 310). The latter included the following:  an immediate change in the shape of the heart at the end of the diastole compared between on earth’s gravity and microgravity. With a mention of a few effects, constant exercise for the astronauts at the in space would keep them healthy at the almost or zero gravity. A similar activity of exercise should be adopted by people on earth who have heart limitations and disorders in order to keep them healthy (Perry 201).

During the study, Thomas and the research team conducted a training of twelve astronauts to get a picture of their hearts through use of an ultrasound machine or equipment on the station of the international space. Pictorial images were taken before, during and after the time spent by the astronauts in the space. In space, it was observed by looking at the images that the heart became more spherical by a percentage of nine in comparison to its size and shape on the earth (Simmons 300).  Mathematics models suggested that it was almost an exact prediction. It was hence suggested by Thomas these models, would provide doctors with an improved understanding of the conditions of the heart on earth.

The spherical shape or nature of the heart implied that the heart functioned in a less efficient manner. This condition appeared to be provisional or temporary.Upon their return to earth, the shape of the heart returned back to its normal shape (Caiozzo 601). The scientists had no idea whether there could exist effects as a result of the change in the hearts’ shape.

The astronauts experienced being light-headed or passing out as a result of a spontaneous drop in pressure of the blood on standing up on an immediate return to the earth. This condition is commonly known as orthostatic hypotension (White 405).  Travel to space is also common to causing irregular heartbeats. In addition to this, the increase in radiation experienced in the space may also result in speeding up of the arterial hardening or atherosclerosis (Covault 901).  The researchers are currently compiling and adjusting their models in relation to the conditions that include disease of the coronary artery which forms the most frequent fatal disease of the heart experience in the entire world (Iwasaki 345). Besides the coronary artery disease is the hypertrophic cardiomyopathy which relates to the heart muscles thickening and eventually leads to the limitation of the heart ability and efficiency in pumping blood.

The force of gravity poses several impacts on the normal flow of blood in human body. These effects are both negative and positive on human blood flow.

Complications of gravitational force on blood flow

The force of gravity forms a barrier to the flow of blood to the various body parts through arteries. This barrier formed by the force of gravity is thus always broken through arterial blood pressure which normally overcomes the fluid gravitational pressure (Iwasaki 321). For example, whenever one stands, the difference in pressure between his or her heart, level of reference, and the veins in the leg is normally the pressure as a result of the column of the blood that is a little denser than that of water and is approximately a thousand  millimeter tall similar to about 70mmHg. Similarly, the resting blood pressure of systolic is roughly 130mmHg. In addition, when one is the right way up, the brain receives blood from the heart through systolic pressure of approximately 50mmHg. Eventually, even when one stands on the head, the heart can facilitate blood to all parts of the body (Connors 301).

In contradiction, the force of gravity is of importance during the return of blood from the head or brain to the heart and other lower parts of the body. Parts of the body on the lower end hence possess an opposite challenge in comparison to the first scenario since the force of gravity attempts to pull down the blood in venous vessels and the pull, when one stands, is always higher in comparison to venous pressure (Woodard 402). The inner veins of the lower limbs normally possess an adaptive feature of enabling the leg muscles to perform the pumping role through utilization of valves. The veins are thus squeezed by the contracting of the leg muscles hence blood strictly flows towards the direction allowed by the valves, the heart in our case. On the relaxation of our muscles, the veins are filled with blood from the capillaries. The squeezing of the muscles normally do not occur in situations where one is seated or stands on a long duration of time and occasionally feet swells since fluids pass out of the transportation vessels into the space of interstitial (Burton 521).

In relation to the similar concept, arm veins also have valves through the blood flow and balance idea is achieved on its own and not exactly through squeezing. Whenever the arm is raised or lowered, blood is moved out of the arm through force of gravity when the arm is raised but its backflow is restricted in the occurrence that it is lowered (Vil-Viliams 233).

In the absence of the force of gravity in relation to blood and fluid acceleration, there exist crucial and variations that are observable in the system of blood circulation. These vibrational impacts can either be on long term or short-term basis. Gravitational force absence may cause and result in elimination or removal of hydrostatic gradients from the body leading to shifts and shortages of thoracic fluids (Hargens 200). Economics, fluids amounting to two litres shifts to the head and chest from the lower parts of the body which is frequently referred to as bird legs or puffy face resulting to the swelling of the face and neck. This due to protruding of veins at the neck and the skinning of the legs. With time, adjustments are made by the body and the distribution of fluids are brought back to normal and uniform. This is achieved through pressure of the venous as it equalizes across all body parts and reflects the desired pressure in the arteries (Vernikos 780).  

Increase in fluids at the head normally brings about the nasal congestion, frequent headaches and changing eyesight prescription brought about by increased pressure on the eyes. This changes eventually lead to body systems strains in order to adjust the body back to its normal functioning environment during alteration of normal variables. They include baroreceptors which play the role of performing adjustments mechanisms of pumping of blood in regards to current prevailing pressure readings of the body (Zhang 200). For example, under gravity, the heart should possess higher pressure in comparison to the sensors in our sinuses hence whenever the body is the inexperience of the opposite, signals are sent by the baroreceptors for an immediate correction and less functionality by the baroreceptors under no or limited gravity.

 The insufficient gravitational force also results in changing in components of blood. The mass of red blood cells is usually lost due to the frequent blood shifting to the chest from the legs which mislead the body to believe their availability of more than enough blood (Sasaki 300). This eventually leads to the kidney releasing limited erythropoietin hormones which concurrently encourages making of few red blood cells in the bone marrow (Young 201). In addition, plasma volume reduces as a result of an increase in permeability of the capillaries. These will occasionally result in limited oxygen in the blood due to a reduction in oxygen carried within the blood hence leading to increasing blood viscosity. 

Gravity is very significant in the flow of blood in human as discussed above, in a case where the gravity is low or there in no gravity there are some complications which affects the brain and heart as aforementioned. Some of these complications includes becoming very spherical and took a decrease in muscle mass during their expenditure of time in space for a longer duration of time. The legs as well will appear very heavy after standing for a long period of time. Exposure to no gravity has been proven to have some harmful effects on human health. Humans are well-adapted to the physical conditions at the surface of the earth, and so in response to weightlessness, various physiological systems begin to change, and in some cases, atrophy. Though these changes are usually temporary, some do have a long-term impact on human health.

Short-term exposure to microgravity causes space adaptation syndrome, a self-limiting nausea caused by derangement of the vestibular system. Long-term exposure causes multiple health problems, one of the most significant being loss of bone and muscle mass. Over time these deconditioning effects can impair astronauts' performance, increase their risk of injury, reduce their aerobic capacity, and slow down their cardiovascular system. As the human body consists mostly of fluids, gravity tends to force them into the lower half of the body, and our bodies have many systems to balance this situation. When released from the pull of gravity, these systems continue to work, causing a general redistribution of fluids into the upper half of the body. This is the cause of the round-faced 'puffiness' seen in astronauts. Redistributing fluids around the body itself causes balance disorders, distorted vision, and a loss of taste and smell.

And some of the newest advantages regarding medical application are as follows, the increase in the volume of fluid in the chest as a result of absence or limited force of gravity sometimes leads to a decrease in the anti-diuretic hormone and simultaneous release of aldosterone that concurrently brings about the production of more urine and a thirst decrease. Muscles of the heart do not necessarily need to performer excessively during this situation of limited or complete absence of the force of gravity (Clement 212). Normally, shrinking of the heart is experienced, the volume of blood and other fluids reduces and eventually pressure of the blood decreases. This has helped doctors in determining the roles played by the force of gravity on the diseases such as postural orthostatic tachycardia syndrome.

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