Fatigue and Motorcycle Touring
Don Arthur, M.D.
the sun sets and the miles pass, fatigue becomes our shadow but never our friend. The pleasures of a riding vacation can melt
into frustration if a rider pushes the day’s miles beyond his or her abilities. This article discusses the elements
of fatigue, how to recognize its subtle signs, and how to ride more safely.
brains are complex organs that fatigue during waking hours, accumulating a physiologic debt that is repaid only by sleeping.
During sleep, the chemical balance is restored in those areas of the brain which are required for conscious activity. This
cycle is normal and immutable. The exact mechanism has been extensively studied and is so complex that, for all practical
purposes, it could be called ‘magic.’
individual requires a specific, genetically set, amount of sleep. Most people require about 8 hours of sleep but the ‘normal’
range is somewhere between 6 and 10 hours. Einstein required 10 hours of sleep each night. Sleeping 2 hours less than required
significantly decreases one’s performance and alertness. These affects are cumulative – sleeping less each night
eventually results in a sleep ‘debt’ which must be repaid to return the brain to baseline function. The good news
is that the debt does not have to be paid in full hour-for-hour but it must eventually be paid by obtaining deep sleep, not
multiple short naps. Unfortunately, one cannot ‘bank’ sleep – accumulate sleep in anticipation of the need.
Our internal physiologic clocks regulate all of our body’s automatic functions – including
the sleep-wakefulness cycle. Each person is programmed with his or her own requirements and cycle times. This internal clock
tries to keep us on a ‘normal’ 24 hour sleep rhythm and is synchronized to light (day) and dark (night) cycles.
Traveling through different time zones shifts
the clock forward or backward, temporarily disrupting the normal circadian rhythm. In general, accommodation takes one day
for every time zone traversed.
deprivation at night has two effects. Our body’s sleep center interprets darkness as a signal to initiate sleep. Compounding
this circadian signal, the lack of stimulation and visual cues at night deprive the brain of the activity which would help
maintain alertness. Without the higher level of stimulation offered during daylight hours, our brains more easily slip into
the sleeping mode. Increasing external stimulation may help extend wakefulness by temporarily overcoming the circadian preference
to induce sleep. Studies have shown that physical fitness also seems to allow individuals to tolerate circadian rhythm shifts
have also documented a Drone Effect which describes individuals who become momentarily functionally
incapacitated, also known as “microsleeps.” These periods manifest as a few
seconds of open-eyed sleep, paralysis, blurred vision, or other effects of which the victim might be unaware except for a
vague feeling of having missed something – parts of a conversation or a section of highway. Traveling at 70mph (113kph),
a rider covers 103 feet (31 meters) per second – that’s the length of a football (football) field in just 3 seconds.
brains are marvelous computers but they grow weary of constant activity and must be refreshed. Much like an hourglass, our
mental processing power slowly ebbs as the fatigue debt increases. The transition affects all performance functions and occurs
in such an insidious, gradual manner that we are not usually aware of the decrement. This is especially true if we are engaged
in a high skill or high tempo activity where the activity distracts attention from the growing fatigue
responses to fatigue are individual, there are three common factors that seem to predicate one’s functional decrement:
(1) task skill level, (2) level of training, and (3) inherent
biological factors. The more practiced and proficient one becomes in a given task and the
more complex the task, the greater is the resistance to fatigue. Likewise, greater levels of training and experience seem
to have protective effects. We cannot control genetically imprinted biological functions but we can certainly affect skill
and training levels. In general, less experienced riders are at greater risk than
those who have built up their experience level, giving more credence to the wisdom of slowly building one’s riding limits.
Sleepiness. While it might seem obvious
that sleepiness would result from fatigue, we must keep in mind that our brains interpret fatigue as a signal to sleep. The
greater the fatigue, the stronger will be the sleep center’s inducement to sleep. This may trigger sleep even when unintended
– and unanticipated. Microsleeps are one manifestation of the body’s drive to
obtain the rest needed to reverse the effects of fatigue. Microsleeps may occur during periods of otherwise normal and highly
functional activity, causing unexplained variable and unpredictable performance. Concentration failures can occur during periods
of activity which appear otherwise normal.
may occur during periods of otherwise normal and highly functional activity, causing unexplained variable and unpredictable
can manifest as failure to recognize hazards, failure to take appropriate action in the face of an emergency, inability to
make decisions, inability to concentrate, loss of time, failure to negotiate a turn, forgetfulness, and many other symptoms
which can be disastrous to a motorcyclist. The greater the fatigue, the greater is our tendency to underestimate the fatigue
burden and magnitude of the drive to sleep. This adds to the danger of unrecognized fatigue effects.
As our ‘computing’ power and speed decrease when fatigued, our ability to gain and process new information becomes
impaired. The slower we receive and appreciate information, the more delayed our responses become. This is manifest in slower
decision- making and longer reaction times. Overall, this reduces our vigilance and increases our risks.
common symptom of profound fatigue is traveling at a much slower than normal speed. This happens because the brain is processing
riding information (apparent speed over the road, scenery passing, motorcycle vibration, wind pressure, etc.) more
slowly. Thus, a slower speed may take up the same amount of available brain computing power as normal speed does when the
brain is rested. The speeds feel the same to our fatigued brain.
and other effects are exacerbated at night. As our darkened surroundings provide fewer clues to reality, our mind has less
data with which to make proper decisions. As fatigue increases and cues decrease, judgment becomes increasingly faulty. Our
minds may ‘fill in’ our perception gaps, causing us to perceive things which are not real. Mistaken perceptions
– even hallucinations – are possible as our minds fill in the picture or our surroundings when real data are unavailable
or are missed.
� SYMPTOMS OF FATIGUE WHILE RIDING
Slow reaction time
Braking hard to avoid a hazard
� Spilling drinks
slower than normal
Being surprised by a passing car
seeing deer or other road hazards
a gas stop when low on fuel
your wallet after fueling
your spouse’s birthday call
� Impaired decision-making
Not stopping to rest when tired
Taking an inappropriate route
to choose from a diner menu
Loss of situational awareness
to recognize a stop sign or signal
Not putting the kickstand down
Failing to put feet down when stopping
in a high gear
to ‘go’ when light changes
Inserting eye drops while wearing glasses
Inability to calculate purchase amounts
Inability to formulate routing plans
to communicate with riding buddies
Fixating on a task
impairs memory – our ability to store new information and retrieve old information. Stories abound about riders who
are critically low on fuel but ride past an open filling station, ‘forgetting’ to stop. Unfortunately, these lessons
wait to be learned again and again, even by experienced riders.
dangerous and insidious effect of fatigue is refusal to recognize the need for sleep and inability to take effective action.
information processing becomes more difficult, our tendency is to choose options which require the least efforts or have the
least risk even if the choice has a lower probability of success than one which is more complex and requires greater thought.
We can become fixated on a task and be unable to resolve conflicting thoughts or decision criteria. This could result in effective
immobilization, loss of situational awareness, or skipping critical safety actions.
Psychological changes. As fatigue increases,
sleep becomes an increasingly prominent focus, both consciously and subconsciously. Mood
slowly degrades, interfering with socialization functions. This further adds to one’s stress and compounds the difficulty
in communicating with others.
also affects one’s motivation as the brain increasingly focuses on satisfying the
fatigue debt. This decreased motivation may result in a change in other habits such as eating and drinking less. This can
be disastrous if dehydration is added to fatigue.
we become increasingly unable to perform tasks normally and inhibitions wane, we can become impatient, frustrated, and angry.
dangerous and insidious effect of fatigue is refusal to recognize the need for sleep and inability to take effective action.
are several things you can do to prepare for a period when you expect less sleep than normal:
Don’t start a fatiguing activity in a sleep deficit. Obtain your normal rest for several days prior to the activity.
If you’re going to start an activity early in the morning, try to phase your sleep so you get your normal rest time
before awaking. In other words, if you require 8 hours of sleep but will start an activity at 6 am, try to be asleep at 9
pm the prior evening and give yourself time to awaken and prepare for the day’s activities.
Proper nourishment and hydration is an important preparation. Eating three small meals each day is preferable to having one
or two larger meals. Your brain needs the energy sources food supplies – so breakfast is important. Because the body’s
circadian rhythm produces a natural drowsiness in mid-afternoon, a protein and carbohydrate snack can help stave off this
not overeat. Large meals are hard to digest and shunt blood and energy away from the brain. Many small meals are better than
a few large feasts.
Put your mind at rest.
Have all your pre-ride preparations done before retiring the night before a long ride. Tie up the loose ends which might interfere
with your ability to rest.
Many studies have shown that people who are physically fit are more able to tolerate the effects of fatigue. A long-standing
daily routine should maintain tone and endurance. Carrying less weight will also reduce riding fatigue.
Prepare your ride.
Your motorcycle should be configured to increase your comfort and decrease the work of riding. Make sure you have a routine
and all your equipment is thoroughly road tested. Your bike should fit you, not vice versa.
are some important aspects of ride preparation:
� PREPARING YOUR RIDE
riding suit, boots, gloves
and cooling aids
lip hydration and sun protection
Ergonomics – your bike must fit you
fitted and comfortable seat
foot peg and control locations
in the same place every time
used things on top
to find everything in the dark
� Repair kits
tools you’ll need
Pack a tire
repair kit and means of inflation
to use them!
Communication – your link with others
CB or FRS
– for when you’re stopped
Caffeine can be useful in helping extend fatigue tolerance. But, its effectiveness is greatly enhanced if used sporadically.
If you rely on caffeine every day, your body will expect its normal supply. If you don’t consume your ‘normal’
amount of caffeine, you will likely experience fatigue sooner than someone who seldom drinks caffeine. This is one stressor
you don’t need while riding.
you are unaccustomed to caffeine, consuming some can help stave off some of the effects of fatigue.
Alcohol and riding don’t mix and should be avoided for several days prior to a ride. The toxic products of alcohol metabolism
adversely affect brain activity long after the noticeable effects have disappeared. Alcohol also interferes with the body’s
ability to properly process other nutrient sources.
and caffeine are also diuretics – they cause increased urination. This has two negative effects for riders. Most important,
it causes dehydration which can adversely affect performance and increase susceptibility to fatigue. Also, increased urination
means more frequent unscheduled stops.
Motorcycle and equipment. As just described,
your bike should be configured to produce the least fatigue. Put another way, you should eliminate those things which increase
the ‘work’ of riding or contribute to developing fatigue. Your motorcycle and all its equipment should be second
nature to you – as familiar in the dark and rain as in your garage.
windshield sufficient to significantly reduce wind pressure and deflect rain will considerably increase fatigue tolerance. Fatigue ensues much
more rapidly when a rider is continually bracing against wind pressure, using torso and leg muscles to remain upright and
arm muscles to grip the handlebars. Rain adds another significant level of stress that a good laminar flow windshield will
alleviate. Laminar flow windshields direct air up and over the rider and are designed to minimize a motorcycle’s aerodynamic
how the constant din of road noise can induce fatigue. Hearing protection significantly
decreases this stress. Although not intuitive, most disposable hearing protection cuts out the background noise of the road
while allowing conversation and other meaningful sounds to be heard more clearly. They will also decrease the long term hearing
loss associated with exposure to constant environmental noise.
The ride. There are many aspects of
the actual ride which can affect the accumulation of fatigue debt. The more challenging the ride, the more fatiguing it will
be. Some riding factors which most quickly produce fatigue are:
- Severe time constraints
- Bad weather
- Excessive heat or cold
- Unfamiliar roads
- Monotonous scenery
- Extended night riding
- Increased threats – wildlife and traffic
- Riding conditions beyond the rider’s ability
- Complex tasks required while riding
- Distractions – mechanical or family problems
Although many of these
factors cannot be totally avoided, their impact can be somewhat controlled. Severe time constraints can be minimized by properly
planning one’s route. Don’t bite off more route than you and your bike can swallow. Leave a time and distance
cushion toward the end of your route. Know your limits ahead of time and stick to them.
Make a promise to yourself and others… write it down. Plan your ride, then ride your plan. Don’t try to extend
the ride on the fly, when fatigued.
most effective ‘nap’ is one which lasts at least 5 minutes but not longer than 45 minutes.
There is no substitute for sleep in paying the fatigue debt. Once fatigued, functional ability must be refreshed by
replenishing the brain’s nutrients and restoring its very delicate chemical balance.
an hour-for-hour sleep payback isn’t required. But prolonged, solid sleep is necessary to bring the brain back to a
pre-fatigue level of function. Repetitive sleep deprivation has a cumulative effect; the longer you wait to repay the debt,
the more sleep will be necessary.
sleep is better than no sleep but merely resting is no substitute for sleep. Performance tests have shown improved mental
and physical function even after very short naps regardless of whether a person notices the difference. Research has shown
that any amount of sleep over 5 minutes is helpful and will have a cumulative effect. The more naps taken, the better. Waking
from a nap longer than 45 minutes but less than 2 hours can cause “sleep inertia”, a state of groggy disorientation
which lasts 15-20 minutes. Thus, the most effective ‘nap’ is one which lasts at least 5 minutes but not longer
than 45 minutes.
hours of continuous sleep ensures a complete sleep cycle. Therefore, one should sleep for at least 2 hours if choosing to
nap for more than 45 minutes.
body’s normal circadian sleep rhythms tend to favor sleep between 2 am and 8 am as well as between 2 pm and 5 pm. Therefore,
timing naps to coincide with the internal circadian clock will allow you to fall asleep more quickly and will enhance the
naps are taken, you should seek a comfortable location which will allow uninterrupted sleep with minimal external stimulation.
is perennial debate about whether to combine gas, meal, and rest stops. Many experienced riders advocate taking gas and meal
stops separately from rest stops to decrease fatigue by breaking riding time into manageable segments. A converse argument
can be made that, since meaningful rest cannot be accomplished without sleeping longer than 5 minutes, separating rest stops
from gas/food stops doesn’t truly decrease one’s fatigue debt. It’s your ride; you decide.
cannot overcome fatigue! You must learn to recognize it and take effective action – REST! No ride is worth your life!
Socialization. Maintaining interactive
contact with others is a way of increasing wakefulness in the short term. Since language is a very high intellectual function,
talking with someone (even on the CB) is often helpful in maintaining wakefulness. However, if profoundly fatigued, one will
be even more prone to falling asleep immediately after the conversation ends.
Exercise and other external stimulation. Walking or performing exercises will help increase alertness because the physical activity requires
concentration and increases blood flow. However, vigorous activity may only increase fatigue by rapidly depleting nutrient
stores and adding muscle fatigue to existing body stress. Standing on the motorcycle’s foot pegs, letting the wind hit
your face, eating hot candy, and the many other ‘tricks’ only serve to temporarily increase wakefulness. Their
effects are very short-lived and do not remove any of the fatigue debt. Rest is still the answer!
Nutrition and hydration.
Maintaining proper hydration is essential in staving off the effects of fatigue. Dehydration can be deadly when combined with
the summer heat and insensitive (non-sweating) water loss which occurs while riding. Dehydration significantly decreases mental
and physical functioning and can accelerate fatigue and dramatically magnify its effects. Symptoms of dehydration include
headache, nausea, dry lips and mouth, muscle weakness, and decreased concentration. Many of the symptoms of dehydration are
the same as those of fatigue.
Solution: Stay ahead of hydration needs.
Drink beverages which will add to body water reserves. Plain or flavored water drinks as well as ‘electrolyte’
drinks (such as Gatorade�) will suffice. Don’t get behind. If you have a headache, you’re already
behind and will need to drink at least a quart (liter) immediately. Many riders carry a convenient water delivery system which
includes a hose from which the rider can drink while riding.
Caffeine. Caffeine can be helpful in
improving wakefulness. However, people who drink caffeine regularly are less sensitive to its effects. To gain maximal effect
from caffeine, a rider should stop ingesting caffeine for several days prior to the time when it’s to be ‘needed.’
use can be strategically timed for maximum benefit. Caffeine is most effective in improving mental awareness in the 100-200
mg (4-8 ounces of coffee) range. It takes approximately 30 minutes to have a peak effect and the effects last 3-4 hours (although
significant amounts of caffeine remain in the blood for many more hours).
caffeine within 8 hours of sleep since it will make falling asleep more difficult, shorten the duration of sleep, and disrupt
the military has experimented with a variety of stimulant drugs, none has reduced the body’s fatigue debt or its need
for rest. They may improve performance and wakefulness for very short periods but do not enhance long-term (days) performance
and can significantly decrease performance after the first dose has worn off. There is no place in
any sport for stimulant drugs, period.
Note: Opinions expressed herein are those of the
author and, although based on scientific facts, should not be construed as guidance and do not substitute for an individual
rider’s judgment. All rides are different and all riders are unique. You should ride your own ride, well within the
limits of your training and experience.