Hypergravity is defined as the condition where the force of gravity exceeds that on the surface of the Earth. This is expressed as being greater than 1 g. Hypergravity conditions are created on Earth for research on human physiology in aerial combat and space flight, as well as testing of materials and equipment for space missions. Manufacturing of titanium aluminide turbine blades in 20 g is being explored by researchers at the European Space Agency (ESA).
All of this is of extreme importance because human physiology and materials are used to build planes, spaceships and structures, which are all accustomed to Earth’s normal gravity. NASA scientists have recently been looking at meteorite impacts, and after testing certain strains of bacteria, they discovered that most strains were able to reproduce under pressures exceeding 7,500 g’s.
Recent research carried out on extremophiles in Japan involved a variety of bacteria including Escherichia coli and Paracoccus denitrificans being subject to conditions of extreme gravity. The bacteria were cultivated while being rotated in an ultracentrifuge at high speeds corresponding to 403,627 times "g" (the normal acceleration due to gravity). Another study that has been published in the Proceedings of the National Academy of Sciences, reports that some bacteria can exist even in extreme "hypergravity." In other words, they can still live and breed despite gravitational forces that are 400,000 times greater than what's felt here on Earth. Paracoccus denitrificans was one of the bacteria which displayed not only survival but also robust cellular growth under these conditions of hyperacceleration which are usually found only in cosmic environments, such as on very massive stars or in the shock waves of supernovas. Analysis showed that the small size of prokaryotic cells is essential for successful growth under hypergravity. The research has implications on the feasibility of existence of exobacteria and panspermia.A concern of this practice is Rapid spinning. If you move your head too quickly while you're inside a fast-moving centrifuge, you might feel uncomfortably like you're tumbling head over heels. This can happen when balance-sensing fluids in the semicircular canals of your inner ear become "confused." Some experiments using centrifuges often include devices that fix the subjects' heads in place, just to prevent that illusion. Traveling through space, however, with your head fixed in place is not practical.
In order to understand and describe the influence of gravity in systems, the observation of behaviour in microgravity and at 1g (where g is the gravitational acceleration at the surface of the Earth) is not sufficient.
Researchers calculated from a weight loss experiment that using 5 lb. ankle weights and 2.5 lb. wrist weights would have a 14% improved NEAT calorie burn while doing household chores. Track and basketball primarily plyometric) metrics improved by 8-25% mostly depending upon if the subjects used weighted vests all day or only when training, but the effect disappeared after a month of not using Hypergravity Training.
Hypergravity effects on rate of aging of rats Ever since Pearl proposed the rate of living theory of aging numerous studies have demonstrated its validity in poikilotherms. In mammals, however, satisfactory experimental demonstration is still lacking because an externally imposed increase of basal metabolic rate of these animals (e.g. by placement in the cold) is usually accompanied by general homeostatic disturbance and stress. The present study was based on the finding that rats exposed to slightly increased gravity are able to adapt with little chronic stress but at a higher level of basal metabolic expenditure (increased 'rate of living'). The rate of aging of 17-mth-old rats that had been exposed to 3.14 times normal gravity in an animal centrifuge for 8 mth was larger than of controls as shown by apparently elevated lipofuscin content in heart and kidney, reduced numbers and increased size of mitochondria of heart tissue, and inferior liver mitochondria respiration (reduced 'efficiency': 20% larger ADP: 0 ratio, P less than 0.01; reduced 'speed': 8% lower respiratory control ratio, P less than 0.05). On the other hand, steady-state food intake per day per kg body weight, which is presumably proportional to 'rate of living' or specific basal metabolic expenditure, was about 18% higher than in controls (P less than 0.01) after an initial 2-mth adaptation period. Finally, though half of the centrifuged animals lived only a little shorter than controls (average about 343 vs. 364 days on the centrifuge, difference statistically nonsignificant), the remaining half (longest survivors) lived on the centrifuge an average of 520 days (range 483-572) compared to an average of 574 days (range 502-615) for controls, computed from onset of centrifugation, or 11% shorter (P less than 0.01). Therefore, these results show that a moderate increase of the level of basal metabolism of young adult rats adapted to hypergravity compared to controls in normal gravity is accompanied by a roughly similar increase in the rate of organ aging and reduction of survival, in agreement with Pearl's rate of living theory of aging, previously experimentally demonstrated only in poikilotherms.
- "Specialty Definition: Hypergravity". Websters Online Dictionary. Retrieved 29 April 2011.
- Than, Ker (25 April 2011). "Bacteria Grow Under 400,000 Times Earth's Gravity". National Geographic- Daily News. National Geographic Society. Retrieved 28 April 2011.
- Deguchi, Shigeru; Hirokazu Shimoshige, Mikiko Tsudome, Sada-atsu Mukai, Robert W. Corkery, Susumu Ito, and Koki Horikoshi (2011). "Microbial growth at hyperaccelerations up to 403,627 xg". Proceedings of the National Academy of Sciences. Bibcode:2011PNAS..108.7997D. doi:10.1073/pnas.1018027108. Retrieved 28 April 2011.