Social

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Subject: 6 Social

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Subject: 6.1 Bicycling in America
From: Jobst Brandt <jbrandt@hpl.hp.com>

(or How to survive on a bicycle)

In America, bicycling appears to be an unacceptable activity for
adults. It is viewed as a pastime reserved for children (people who
are not old enough to drive cars). Adults who sense that they are
violating this stricture, excuse their bicycling by representing it as
the pursuit of physical fitness. They refer to their bicycling as
training rides. Rarely do you hear a cyclist say "we were bicycling"
but rather "we were on a training ride". Certainly most of these
people never race although one might assume, by implication, that
their other rides are races. Some also refer to themselves as serious
cyclists, a term used to describe those who, typically, keep track of
pedaling cadence and other bicycling statistics, thereby giving proof
that they are not engaged in child's play.

In contrast, Europeans seem able to accept bicycling as a proper
activity for all ages. That is to say, motorists do not treat
bicyclists with apartheid and bicyclists do not feel the need to
justify their pursuit as anything other than bicycling, for whatever
reason. In Europe cadence on speedometers is an un-marketable
function for unexplained reasons, however, one could imagine that for
the average cyclist it is a useless statistic, except for those on
"training rides".

With this perception of bicycling in America, non cyclists and some
occasional cyclists are offended by others who bicycle on public roads
in the presence of automobile traffic. "Get the f#%k off the road!"
and similar epithets are heard from drivers, some of whose cars are
equipped with bike racks. It is similar to gay bashing; by expressing
public outrage they demonstrate abhorrence of unacceptable behavior.
The same is true of bicyclists who deride others in public for not
wearing a helmet. Aggressive self righteousness is probably a fitting
description.

Another motive behind such behavior may be a sense of dissatisfaction
with ones life. Anyone who is perceived as having fun, or at least
more fun than the subject, needs to be brought down a notch.
Psychologists who have interviewed youths that go "wilding" have
gotten responses to the effect that "my life is terrible and I can't
stand people who are having fun". So these youths attack others and
beat them bloody. In a manner that may not make sense to others, they
bring their victims down a notch to achieve parity.

There is little doubt that bicycling has its hazards. You can fall by
running into a pothole or an obstacle, by riding into a grating, or
falling on loose gravel or a slick manhole cover. There are enough
hazards without the threat of being run down by a car. However, the
whole sport loses its appeal when motorists, who believe that adult
bicycling is offensive, actively engage in making it a deadly
endeavor.

The scenario:

In a typical encounter a driver says to his passenger "You see that
guy on the bicycle? That's a dangerous place to ride." while slicing
within inches of the cyclist. The passenger is truly impressed with
the danger of bicycling, especially in the presence of this driver.

I don't understand how drivers justify such behavior but I think I
know what is going on.

Examples:

o The buzz and swerve routine:

A driver slices dangerously close even though there is no opposing
traffic. Then he drifts to the edge of the pavement to make clear how
far he went out of his way for the cyclist. The desired path was even
nearer the road shoulder than at the passing point. The buzz and
swerve is executed equally well consciously and subconsciously.

o Center court, extra point:

The car, on a visibly empty stretch of road, travels perfectly
centered between the median and edge stripes, even when this requires
passing within inches of a cyclist. It appears that the driver is
awarding himself points for not flinching when passing cyclists and
extra points for proximity. In the event of a collision it is, of
course, the cyclist who swerved unexpectedly. The precision with
which the driver executes this maneuver, in spite of the danger, makes
the center court game conspicuous. People generally don't drive
exactly centered in a lane, especially when there is an obstacle.

o Honk and slice:

The buzz and swerve or center court routine can be enhanced by honking
a single one second blast. This is usually done at a far greater
distance than a sincere warning toot; about 200 yards works best.
This is a great crutch for the driver who subsequently collides with
the cyclist. "But I warned him!"

o The trajectory intercept:

A car is traveling on a road that crosses the cyclists path at right
angles. The car and bike are equally distant from the intersection
but at different speeds. With skill, the driver of the car can slow
down at a rate that lets him arrive at the intersection at precisely
the same time as the cyclist. The bicyclist who has a stop sign may
now come to a complete stop and wait for the driver who is only
looking out for the cyclist's safety. If the cyclist doesn't stop,
the driver honks and yells something about breaking the law.

Extra points are gained by offering the right of way to the cyclist,
in spite of moving traffic in the adjacent lanes.

o The contrived hindrance:

A driver refuses to pass a cyclist on a two lane road until the
passenger asks how much longer they must follow this bicyclist, or
until the following cars begin to honk. Then, regardless of
visibility or oncoming traffic, an inopportune pass is executed after
which each of following drivers makes it clear when passing that it
was the cyclist who was responsible for the near collision.

o The rear-ender:

While riding down a mountain road, the cyclist catches up with a car
that notices his rapid approach. If an oncoming car approaches the
driver slows down, obviously for safety sake, and then suddenly slams
on the brakes when there is no place for the cyclist to go. Bicycles
cannot stop as fast as cars since cars can safely skid the front
wheels but bicycles can't. This game is the more dangerous variation
of speeding up every time the cyclist tries to pass but to drive as
slowly as possible everywhere else.

One explanation for these maneuvers is that the driver recalls that
riding in the mountains was always too hard and riding down hill was
scary. This cyclist can't do what I couldn't do and I'll show him a
thing or two. Thus the driver proves to himself that not riding in
the hills was for safety's sake, it had nothing to do with physical
ability. It fits into the " I'll teach that smartass a lesson. There
is little risk for the car because in a rear-end collision the vehicle
behind is, with few exceptions, found at fault.

So why does all this go on and on?

It is not as though they are all hostile drivers; some are just
frustrated drivers. They may still be getting even for some bicycle
accident they had in their youth and don't want others to get off any
easier. Some are angry at having to spend the time behind the wheel
while other "irresponsible adults" are playing on their bicycles. I
believe the meanest ones are insecure people who don't feel as though
they are accomplishing what they expect of themselves and don't like
to see others have it any better. Many drivers believe that the only
part of the road to which a bicyclist is entitled is the road
shoulder, unless it occurs to the driver to use that part too.

A bike rack on a car may lead you to believe that the driver has a pro
bicycle attitude. Some people use bike racks to transport family
bicycles to a park where they can be ridden safely without venturing
onto dangerous roads; roads that are meant for cars. Among these
people are some of the strongest opponents of general bicycling. They
take refuge in the belief that, if they should run you down while
playing center court, it would prove that you should bicycle as they
do, and not get in the way of cars.

What to do? Don't fuel the flames. Don't return the rudeness that is
dished out. Take legal action where appropriate (and possible).
Don't posture in traffic drawing attention to some undefined
superiority to people who sit in cars. Don't balance on your bike or
ride in circles in front of cars waiting at a red light. Don't make
moves in traffic that are either discourteous, or at best, awkward but
legal. If you hear loud knobby tires coming, believe it! That guy in
the extra tall pickup truck with the all terrain tires, dual roll bars
and multiple searchlights is not a friend of yours coming close to say
hello. Give him room.

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Subject: 6.2 League of American Bicyclists
From: Erin O'Brien <bikeleague@aol.com>

The League of American Bicyclists, (founded as the League of American
Wheelmen) has been working to improve the quality of bicycling in America
almost as long as there have been bicycles.

In the 1870s the forefathers of bicycling banded together to lobby the
government for more paved roads and to put a stop to antagonistic acts from
other road-users. United in 1880 as the League of American Bicyclists, their
mission has carried on throughout the history of bicycling.

Fashioned after "The Good Roads Movement" of the 1880's, our current agenda
is embodied by the L.A.W. Safe Roads Movement, a comprehensive program that
aims to reduce the number of injuries and deaths to cyclists. Highlights
of this 10-pointaction plan include educating bicyclists and other road
users about thei rights and responsibilities to safely share the road, and
promoting the improvement of road design and maintenance to better
accommodate bicycles.

The League's Effective Cycling program is making great strides to advance
this agenda. Taught by certified instructors, it is the only national
bicycling education program that combines the technical training needed to
safely negotiate any traffic situation, with the principles of safe,
responsible riding.

L.A.W. sponsors National Bike Month (May), which serves to promote the
various aspects of bicycling. In 1992, L.A.W. founded The International
Police Mountain Bike Association (IPMBA) to address the growing need for
information, assistance, and training to start-up bicycle-mounted police
patrols.

L.A.W. played an instrumental role in the passage of the Intermodal Surface
Transportation Equity Act of 1991 (ISTEA), federal legislation allowing
both for increased spending on bicycling improvements and for bicyclists to
participate in local transportation planning. L.A.W. also publishes the
bi-monthly Bicyclist Advocacy Bulletin, which provides the most
comprehensive, bicycle advocacy and planning information and advice
available in the nation.

In between advocacy and education efforts, L.A.W. manages to find time to
enjoy bicycling. L.A.W.'s national and regional rallies bring together
members from all over the U.S.A. and Canada for great riding and
entertainment, daily workshops include, advocacy, safety, club leadership,
cycling techniques, and more.

Pedal for Power, another division of L.A.W., hosts Across America and
North-Southa rides that raise money for bicycling and various charities of
the rider's choice.

Eight issues per year of Bicycle USA magazine to keep members up to date on
League activities. Regular features include effective cycling tips,
Government Relations and Education columns, cycle news, and an event
calendar. Special issues include an annual Almanac and Tourfinder. L.A.W.
offers national touring services to members including Ride Information
Contacts in every state. While touring, members can also stay in the homes
of more than 600 fellow members, free of charge, through the Hospitality
Homes network.

League members can fly their bikes for free on TWA, America West, USAir,
Continental, and Northwest airlines when they make their travel
arrangements through the Sports National Reservation Center.

L.A.W. is a 501c-3 non-profit organization with membership of more than
24,000 bicyclists and 500 affiliated clubs and coalitions nationwide.
Individual membership costs $25/year or $30 for families. Advocacy
membership, which includes the bi-monthly Bicyclist Advocacy Bulletin costs
an additional $10/year.

To join the League of American Bicyclists send your membership contribution
to 190 W. Ostend St., Suite 120, Baltimore, MD 21230-3755, or call (410)
539-3399. For membership by phone call 1-800-288-BIKE. For a membership
form to pay by credit card see the "How to Join League" file.

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Subject: 6.3 Rules for trail riding
From: Roland L. Behunin <behunin@oodis01.hill.af.mil>

The Salt Lake Ranger District of the Wasatch-Cache National Forest has
some guidelines for trail riding in their district. Here they are:

1. Yield the right of way to other non-motorized recreationists.
People judge all cyclists by your actions. Move off the trail to
allow horse to pass and stop to allow hikers adequate room to share
the trail.

2. Slow down and use caution when approaching another and make your
presence known well in advance. Simply yelling bicycle is not
acceptable.

3. Maintain control of your speed at all times and approach turns
anticipation of someone around the bend. Be able to stop safely within
the distance you can see down the trail.

4. Stay on designated trails to avoid trampling native vegetation, and
minimize potential erosion by not using wet or muddy trails or
shortcutting switchbacks. Avoid wheel lockup. If a trail is steep
enough to require locking wheels and skidding, dismount and walk your
bike. Locking brakes contributes to needless trail damage. Do not
ride cross-country. Water bars are placed across to direct water off
the trail and prevent erosion. Ride directly over the top, or
dismount and walk your bike.

5. Do not disturb wildlife or livestock.

6. Do not litter. Pack out what you pack in and carry out more than
your share whenever possible.

7. Respect public and private property, including trail use signs, no
trespassing signs, and leave gates as you found them. If your route
crosses private property, it is your responsibility to obtain
permission from the landowner. Bicycles are excluded from designated
Wilderness Areas.

8. Always be self sufficient. Your destination and travel speed will
be determined by your ability, your equipment, the terrain, and the
present and potential weather conditions.

9. Do not travel solo in remote areas. Leave word of your destination
and when you plan to return.

10. Observe the practice of minimum impact bicycling. "Take only
pictures and leave only waffle prints."

11. Always wear a helmet.

12. If you abuse it-you lose it!. Since mountain bikers are
newcomers to the forests, they must prove to be responsible trail
users.

From personal experience, you may also want to add the following
information:

13. In National Parks and National Monuments bicycles are considered
vehicles and restricted to roads.

14. On BLM land - ride only on roadways, trails, and slickrock. The
desert crust (microbiotic crust) is fragile and takes up to 50 years
to recover from footprints, waffle tracks, etc.

15. When camping out of improved campsites camp at least 500 feet
off the road or trail. Try to leave no trace of your campsite.

16. Toilets in unimproved areas - move off trail, and dig a 1 foot
deep pit, cover after use.

------------------------------

Subject: 6.4 Commuting - Is it possible for me to commute by bike?
From: royce@ug.eds.com (Royce Myers)

Not everyone can commute to work on a bicycle. Some people can't cycle to
work in a reasonable time because of their fitness or because they live
too far away. Other people need their cars for their jobs, or take
children to school. Some employers frown on bicycle commuting, and don't
provide any facilities. All these obstacles can be surmounted.

If you want to commute by bike, you will find a way to do it.

A few facilities at your workplace can make commuting easier.

Minimally there should be racks in a well trafficked area. Some business
will let you park them in your cube, and others might provide a closet or
unused room to store them. My company provides enclosed lockers. If
theft is a significant danger, consider buying a second, inexpensive bike
to be used only for commuting.

If your commute is short, and the dress code where you work is relaxed,
you won't need to change or clean up after getting to work. The rest of
us need to prepare for work.

Every workplace has a bathroom where a sponge bath and change is
possible. If you're lucky (like me) there's showers and lockers. If your
ride makes you sweat a lot, and there is no way to take a shower at work,
look around for a nearby gym. Sometimes you can arrange to change and
shower there, then walk or ride slowly to work. If you want to get a
workout, but there's nowhere to clean up at work, try getting your workout
on the way home, making little or no effort on the way to work.

If your ride is too long for a round trip, and there's no place to park,
put your bike in your car and drive to work on Monday. Monday night, ride
home. Tuesday morning ride to work and put your bike in the car. If
you're tired Tuesday night, drive home. If there is a vanpool to work,
get the vanpool driver to mount racks. Then you can take the vanpool in
the morning and ride home in the afternoon.

Some people reduce the length of their commute by driving to a "park and
ride" area, then riding in from there. Another way to solve a long
commute is to find out about bicycle accommodation on buses or other
public transportation. Many people use a combination of bikes and buses,
subways, or trains to make a long commute possible.

Racks, bags and panniers: Some people drive in clothes once a week and buy
lunch at work so they don't need to carry much on their bikes. Others
need something to carry paperwork, lunch and clothes. A lot of commuters
use knapsacks rather than putting racks on a bike, but this raises their
center of gravity and increases wind resistance. Racks can be put on any
bike, and they come in handy for running errands, touring and unsupported
rides. If you're looking for a commuting bike, get one with rack eyelets
on the frame for convenience. Another alternative are touring saddle
bags, which are hard to find but are very handy on bikes without racks.

Get your bike in shape. Replace tires which have cracked sidewalls, or
worn casing. Carry a flat kit, a spare tube and enough tools to fix a
flat. If you're not mechanically inclined, have a bike shop tune up your
bike. Check every part of the drivetrain for lubrication and wear. Make
sure your wheels are true, and that the hubs are lubricated and adjusted
properly.

Contributors:
[I did not retain the mail address of contributors who posted to the group
without a sig; also, I may have missed some posts that weren't emailed to
me]

drobinso@mendel.une.edu.au
ilana@niwot.scd.ucar.EDU
burrows@bcu.ubc.ca
jlbell@presto.eecs.umich.edu
jones@greg.cs.usu.edu
banders@netcom.com
curt@cynic.portal.ca
doosh@netcom.com
"td"
"Robert"
ae505@yfn.ysu.edu
cs4601ah@coral.cs.unm.edu
tbd@dfw.net
timlee@netcom.com

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Subject: 6.5 Commuting - How do I choose a route?
From: royce@ug.eds.com (Royce Myers)

According to the U.S. Uniform Vehicle Code, drivers of bicycles have the
same rights, and the same responsibilities, as drivers of other vehicles.
This means that commuters may use any road, street or highway they want,
and that they must obey traffic laws. Some states vary from the UVC, and
of course, some countries treat bicycles diffently than the US does.

John Forester, in his book Effective Cycling, suggests that all cyclists
use the following traffic principles:

"1. Ride on the right-hand side of the road, not on the left and
never on the sidewalk.

[Note: this is specific to those countries which drive on the right hand
side of the road, like the US. In countries like the UK, you should ride
on the left side of the road.]

2. When approaching a road that is larger than the one you are on, or
has more or faster traffic, you must yield to traffic on that road.
Yielding means looking and waiting until you see that no traffic is
coming.

3. When preparing to move laterally on a roadway, you must yield to
traffic in that line of travel. Yielding means looking forward and
backward to see that no traffic is in that line of travel.

4. When approaching an intersection, you must choose your position
according to your destination. Right-turning drivers are at the curb, left
turning drivers are at the center, while straight-through drivers are
between them.

5. Between intersections, you choose your position according to your
speed relative to other traffic. Parked ones are at the curb, medium-speed
drivers are next to them, while fastest drivers are near the center of the
road."

Transportational cyclists want to maximize safety and minimize time.
Usually the most direct route between the cyclist and work will be the
best choice, but other factors may come into play.

Facilities: Multi-use paths (trails shared with bicycles, pedestrians,
skaters and sometimes horses) are less safe than the road, according to a
recent study published in the Institute for Transportation Engineers
journal; this kind of facility is more likely to send cyclists to the
hospital than comparable streets. Pedestrians, pets and skaters are
unpredictable and require more skill to pass safely. Sidepath
intersections are very dangerous because motorists don't expect vehicular
cross traffic.

Roads with wide curb lanes are safer than narrow roads, but narrow roads
may be ridden safely by using an entire lane. Bike lanes may be as safe
as the same width roads without lanes as long as the rider is competent to
avoid their dangers (e.g., they direct cyclists into right turn lanes,
when the cyclist should normally ride to the left of the right turn
lane). In California, cyclists traveling at less than the speed of
traffic must remain in the bike lane unless preparing for a left turn or
avoiding a hazard, like parked cars, a slower cyclist, rough pavement or
debris.

Traffic: even though arterials usually faster and more convenient than
side streets, riding on side streets may be more enjoyable due to lower
traffic noise and better scenery. Some cyclists are willing to ride the
Huntington Beach multi-use path during the summer even though the fastest
safe speed is 5mph. The view is very nice.

The compromise among pleasure, safety and time is yours.

Once you set your priorities, scout a few routes. Get the best street map
you can find and highlight streets that you like. US Geological Survey
maps (1:24000 scale) also show the hills, which is handy. They're
beautiful maps, too. They look nice on a wall.

Contributors:
[I did not retain the mail address of contributors who posted to the group
without a sig; also, I may have missed some posts that weren't emailed to
me]

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Subject: 6.6 Commuting - Do I really need to look that goofy?
From: royce@ug.eds.com (Royce Myers)

Before I started cycling I had no idea why cyclists wore such silly
looking clothes. Now I know why, but I still think we look silly. The
value of using cycling clothes on a commute depends on the length of the
commute. It is hardly worth it to ride 1 mile to work in cycling clothes
and then change to regular clothes at work, but 20 miles is a different
story.

How to dress for the road, from the ground up:

1. Shoes: if you have a short commute with little climbing, virtually any
kind of shoes and socks will do. I have seen commuters wearing cowboy
boots moving at around 15 mph. If you expect to exert yourself for any
length of time, some trade-offs should be considered. Socks made of
cotton will retain moisture, while polyester type socks (e.g., Coolmax)
will wick moisture and encourage it to evaporate. Cycling shoes are
stiffer than casual or dress shoes, so transmitting energy to the pedal is
more efficient. On the other hand, they are not comfortable to wear off
the bike, so a change of shoes is necessary at work. For most of us, this
is not a problem because shoes take up little space and can be left at the
office. There are a range of options in cycling shoes, depending on your
pedal choice.

A note about pedals:

- Flat pedals allow easy on-off and may be used with any shoes. If you
hit a bump your feet may leave the pedals, which can result in loss of
balance and a crash.

- Toe clips and straps keep your feet on the pedals. They are designed to
be used with cycling shoes, either touring shoes, which have a sole
designed to hook onto a pedal, or racing shoes, which have cleats that
lock the cyclist to the pedal and improve efficiency. Many people
consider clips and straps to be obsolete, but they are a low cost way to
improve your efficiency. They will work adequately with street shoes and
hiking boots, which some people consider an advantage.

- Clipless pedals attach your shoes to the pedals similar to the way skis
attach to boots. With practice you can step in and out of them as easily
as flat pedals, but they are more efficient than toe clips. These pedals
require shoes that are compatible, and are much more expensive than toe
clips. I use the SPD style of clipless pedals, which has a recessed cleat
allowing you to walk around off the bike. I wouldn't recommend extensive
walking in these shoes, but they are perfect for what I need.

- Some pedals are flat on one side and clipless on the other, which allows
the rider to choose to wear cleated shoes for performance or regular shoes
for utility trips.

- An adapter is available for some clipless pedals that will turn them
into flat pedals with toe-clips.

2. Shorts: Casual cyclists ride at low speeds, at low RPMs, for short
distances so no special shorts are necessary. If you ride for any
distance you will need to develop a high RPM (80 - 110) for efficiency.
When your legs are moving that fast, baggy clothes will chafe, as will the
the seams in ordinary underwear, so you'll need something clingy like
lycra. And if you exert yourself, you will need to have some kind of
liner in these shorts to wick moisture from your privates. Bicycle shorts
are meant to be worn with no underwear; they are usually made out of lycra
and are lined with wicking pads. A good pair of bike shorts makes long
rides a pleasure; in fact, I never get on my bike without them.

3. Jerseys and shirts: Cotton retains moisture, so if you sweat, cotton
will keep it next to your skin, making you feel sticky and soggy. Yecch.
Polyester fabrics are designed to wick moisture away from you and allow it
to evaporate quickly. Bicycle jerseys are made out of polyester, and are
cut longer in the back because cyclists usually ride leaning forward to
reduce air resistance. Also, jerseys normally have two or three pockets
in the back, handy for carrying a handkerchief, banana, etc. When I take
my kids on rides I'll wear a tee shirt because I'm not going to sweat
much, but I always wear a jersey on my commute. Some people like cotton
and other natural fibers because they don't retain odors as much as the
polyester fabrics. In cool weather, wool is ideal.

4. Gloves: gloves will make your commute much more comfortable, and will
offer some protection in a crash. Long fingered gloves really help you
stay warm when it's chilly.

5. Eyewear: If you are commuting at dawn or dusk, you should consider
wearing clear glasses to protect your eyes from debris kicked up by cars
and wind. In daylight, sunglasses are a necessity to protect against UV
as well as road hazards.

6. Helmet: A helmet offers some protection in a crash, but the best way to
survive a crash is to learn to avoid falling in the first place. I wear
one, but I don't think it's some kind of magic talisman.

7. Other equipment: If there are unpredictable rains in your area, carry
rain gear. The articles on riding in the winter are availble through ftp
from:

ftp://draco.acs.uci.edu/pub/rec.bicycles/wintertips
ftp://draco.acs.uci.edu/pub/rec.bicycles/wintertips.pam

If you might work late, carry a light. Articles on lights are available
through ftp from:
ftp://draco.acs.uci.edu/pub/rec.bicycles/arnie.light
ftp://draco.acs.uci.edu/pub/rec.bicycles/lights
ftp://draco.acs.uci.edu/pub/rec.bicycles/lights2

Contributors:
[I did not retain the mail address of contributors who posted to the group
without a sig; also, I may have missed some posts that weren't emailed to
me]

------------------------------

Subject: 6.7 Commuting - Do cyclists breathe more pollution than motorists?
From: royce@ug.eds.com (Royce Myers)

The sources for this information vary in credibility, but most of it comes
directly from published studies or other reputable sources like the
Berkeley Wellness letter.

1. Exercise will extend your life by about the amount of time you spend
doing it. So if you spend an hour on your bike, you've added an hour to
your life.

2. Drivers of cars are exposed to up to eighteen times more pollution
than "ambient air", approximately 300 feet from the road. Cyclists share
the road with cars, but they do not trap pollutants, and they take air in
at a much higher position than cars (assuming a diamond frame) so...

3. Cyclists breathe approximately 1/2 as much pollution than cars (this
appears to be _per breath_).

4. Over _time_, a cyclist will breathe much more than a sedentary driver,
since the cyclist is using more than twice as much air. Athletes appear
to be very sensitive to foul air.

5. In general, cycling takes longer than driving, so the bike commuter
may be exposed to pollution for longer periods of time.

6. A UK study found that cyclists had 1/2 the blood level of CO that
drivers did after traveling along a ten mile stretch of congested road.

7. CO blood levels may be less of a problem than inhaled particulates,
which are much harder to measure. Masks make breathing difficult if they
are properly sealed, and are ineffective if they are not sealed.

As a result, the health advantages of commuting by bike depend on several
key factors:

1. Would you exercise anyway? That is, would you drive to the gym and
ride a stationary bike in relatively clean air if you weren't commuting in
traffic.

2. How hard do you ride? The harder you ride, the more air -- and
therefore pollution -- you take in. But then the better the training
effect will be, so if you don't do any other exercise, this is a wash.

3. How long is your drive compared to your ride? If it takes
significantly more time to ride, you may be exposed to more pollution.

4. What kind of car? An open air Jeep would take in and trap less
pollution than a sedan.

The health effects of exercise far outweigh any additional health dangers
from pollution. If you would exercise anyway, though, commuting may not
in your best interest. If you commute on low volume side streets, or on
sidepaths, pollution might not get you, but other hazards might.

Here is a rationalization for those of us who want to believe that
cyclists get less pollution than motorists:

One thing I've noticed about my commute: when I drive, I am _always_
surrounded by traffic. All us cars meet at the light and move from light
to light more or less together. When I ride my bike, I meet cars at
lights, but I don't spend a lot of time around them when they're rushing
past me to get to the next light. The vast majority of time is spent
between packs of cars, without much motor traffic. Since I'm not around
cars very much I can believe:
- I am breathing more garbage than a motorist when I'm in traffic
- I am breathing less garbage than a motorist when I'm not in traffic
- I am not in traffic far more often

Therefore: I am probably getting less pollution on the bike than in my car!

Contributors:
[I did not retain the mail address of contributors who posted to the group
without a sig; also, I may have missed some posts that weren't emailed to
me]