THE USE OF A BICYCLE VELODROME FOR PHYSICAL FITNESS IN LOW GRAVITY ENVIRONMENTS

It has been observed that low gravity environments have a
deleterious effect on physical fitness.  Exercise in a velodrome
track to induce artificial gravity could overcome this problem.

Numerous researchers have found that inactivity combined with
low gravity environments can lead to various health problems. 
Some of these are bone decalcification, poor muscle tone, loss
of muscle mass, and cardiovascular degeneration.

Exercising on a circular velodrome type track (constructed much
like a squirrel cage) will induce artificial gravity for the
subject by radial acceleration.  Jogging or cycling thus become
possible activities which could be beneficial in low G
environments.

There is a problem in starting from rest in micro-gravity
environments since the traction (coefficient of friction X
force) approaches zero.  This could be overcome by various
launching devices, including hand rails, mechanical assists,
velcro surfaces, etc.  Braking and cornering also become
interesting since the tire traction is velocity dependant.

The actual forces involved can be computed from basic equations
of mechanics.

1. a = v^2/r  where a = acceleration
		v = velocity
		r = radius   (^ is used to denote exponentials)
		(note on earth surface 1 G = 9.8 m/sec^2 = 32 ft/sec^2)

Table of track Radius (meters) vs. Velocity (Km/hr) and
corresponding lap time (seconds) for given accelerations:

Radius          Velocity - lap time@

		@0.5 G's                 @1.0 G's
2               11.2 - 4.0              15.9 - 2.8
4               15.9 - 5.6              22.5 - 4.0
6               19.5 - 6.9              27.6 - 4.9
8               22.5 - 8.0              31.8 - 5.6
10              25.2 - 8.9              35.6 - 6.3
12              27.6 - 9.8              39.0 - 6.9
14              29.8 - 10.6             42.1 - 7.5
16              31.8 - 11.3             45.0 - 8.0
18              33.8 - 12.0             47.8 - 8.5
20              35.6 - 12.6             50.4 - 8.9
		 
What does this mean in terms of practical performance
expectations?  A Carl Lewis performance of a 10 second 100 meter
dash equates to 36 Km/hr or about 1 G on a 10 meter radius track
or 0.5 G on a 20 meter track.  An Ed Moser record performance of
50 Kilometers in one hour is about 1.0 G on a 20 meter radius
track.  A recreational jogging speed of about 16 Km/hr is
typical, which requires a 4 meter radius at 0.5 G and a 2 meter
radius at 1.0 G.  A track of this size may feel like climbing 
the walls and be very difficult;  and a 2.8 second lap time may
be dizzying.  A recreational biking speed of about 32 Km/hr is
typical, which requires a 16 meter radius at .5 G and an 8 meter
radius at 1.0 G.  This is still a very small circle, but the
physics and economics of space construction prefer small
structures.  (The assumption was made that standard earth
surface air pressure is maintained and is thus a known
constraint on velocity through wind resistance.)

This raises the question of high G exercise in the earth
environment.  If too little gravity is detrimental then is
increased gravity beneficial?  What would be the effect of
periodic exercise at 2 G's?  A track could be constructed on
earth to test the results of high G exercise.

As points for further research:
What are the sizes of contemporary velodromes?
How many G's are generated?
Where is the smallest, steepest velodrome with the highest
possible G's?

In conclusion, biking in a velodrome track could be used in low
gravity environments to create artificial gravity and counteract
the harmful health effects of prolonged weightlessness. 
Velodrome racing may the sport of the future.

96/12/04 Richard Gray