G-Force and Our Bodies

Posted in Active Bites |
Key Facts: 
  • Our bodies are designed for and require movement: without it, our health becomes compromised
  • What else our bodies require is interaction with gravity: without it, our muscles waste - which compromises bone density and strength
  • The good news is that gravity is a free commodity!
  • Just being more active, on your feet, throughout the day will get you back in touch with gravity and back on the road to health

G-Force on the brain

Our bodies are designed to be in constant motion and our muscles understand how to be lean and strong when they exert effort against gravity.  Muscles can only grow and rebuild themselves if there is gravity, and when leg muscles, bones, the brain and the spine are no longer needed for holding us up and making movements, they become obsolete.  Sitting in a chair at a desk all day has the same effect on our bodies (ie. sends the signal to our brain that gravity is no longer involved) as being up in space does on astronauts' bodies.

Our ancestors relied on gravity to live and survive in a challenging world.   They moved their physical bodies constantly, to find food and shelter, migrating to follow seasons and animal herds, and to avoid danger or to defend themselves.  Our bodies, and our genes, evolved long ago to be in a state of perpetual motion.  We thrive on activity and movement and we age rapidly and get sick from being sedentary.

Our relationship to gravity is so inbuilt that our brain automatically calibrates the amount of G-force and makes the necessary miniscule changes to our balance to ensure we move smoothly and efficiently.  Remember how you ran down stairs without looking, jumped gracefully on a trampoline or balanced effortlessly on tree limbs when you were a child?  This is because a child is so active and their relationship to gravity so constant that their nervous and muscular systems are firing exactly as nature intended.  Our balance is controlled by our inner ears, but this fine mechanism is also something that quickly becomes obsolete in astronauts.  Living in weightlessness means there’s no need for balance in a world with no up or down.

Just like the activities that astronauts returning from space have to practice, we can recover our connection and response to G-force by developing repetitive habits of gentle movement and activity throughout our day.  In case you’re seeing visions of Lycra and treadmills, we can assure you that the type of movement we refer to is very different from the usual exercise associated with gyms!

Increasing the effects of G-force

Our bodies respond to gravity’s stimulus best when:

  • the signals are frequent
  • the activity is low intensity
  • there are stop/start movements
  • the movement is experienced throughout the day and kept constant
  • they are active all day in small ways
  • there is a variety of movement that stimulates more muscles
  • the movements are vigorous e.g. trampoline/skipping/climbing/abseiling/etc
  • they have fun
  • and, when they carry out simple activities and habitual or routine movements e.g. gardening, chopping wood, vacuuming.

Getting into the usual gym-based exercise is not always the best way to engage G-force because the exercises are often geared to strengthen mobilising muscles, capable of force, and not stabilising muscles (your core).  Skeletal muscles are basically either postural to maintain structure (known as stabilisers), or those that move the body (known as mobilisers).  Frequent, low intensity movement and stimulation all day long is what we all need to strengthen our core.  These muscles work well for long periods without switching off, but become weaker when they are not challenged by gravity.

Postural muscles (stabilisers) are easily forgotten because we’re not aware that they’re busy holding our spines straight or keeping our heads up on our necks – until they can’t anymore.  They rely on slow and sustained effort that may or may not result in movement.  But the only way that this sustained effort can be energy efficient is for there to be large numbers of mitochondria (the energy powerhouses) in our muscle cells.

Inactivity reduces the number of mitochondria and muscles weaken as a result.  This in turn disturbs the cellular metabolism of oxygen, leading to more oxygen peroxides (free radicals) being produced in the body, of insulin utilisation causing insulin resistance, and of too many fatty triglycerides accumulating in our muscles because they’re not being used as fuel.

Getting G-force aware

Here are some examples of activities that interact with G-force and enhance the stabiliser muscles:

Standing (frequently), jumping, hopping, skipping, squatting, bending, lifting, carrying, stretching, stretching upwards, climbing stairs, walking up hill and down, getting dressed or undressed, gardening, playing an instrument, dancing, stirring a pot, and small habitual movements like waving hands when speaking, crossing and uncrossing legs, even fidgeting.

Swimming, cycling (great for increasing G-force too), walking and exercises such as yoga or tai chi are also excellent for building strength in core muscles and increasing stamina and bone density.

Sitting is probably the worst crime you could commit against your body because it dramatically reduces the effect of G-force.  Standing, on the other hand, is actually more effective for stimulating health than some forms of exercise because of all the changes required for regulation of blood pressure and blood volume.  The heart is required to pump more blood up to the head and almost every nerve is stimulated too. 

Standing often for short periods of time, especially if seated for most of the day at the office, will ensure the bodily processes are stimulated and that G-force is employed.  If you’re office bound, what about investing in a standing desk?

People who keep moving and maintain levels of activity in later years live longer lives than those who lead sedentary lives.  Why not activate your body’s natural inclination to thrive right now by changing some of your old habits for new ones?  May the G-force be with you!



Sitting Kills, Moving Heals - Joan Vernikos, PhD

Date: 17 October 2014