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1. Introduction:
Australian conditions in summer months can and often do, see the
thermometer climb to high temperatures. Motor sport often sees
participants, be they drivers, crews or officials exposed to the
elements and therefore the familiar “slip, slop, slap, sunscreen,
shade and drink adequate amounts of water to remain hydrated” mantra
is well impregnated in our culture. The practice should be
encouraged for all persons and be adapted as appropriate for motor
sport participants.
2. Objective:
This paper provides a general guideline for all participants
involved in motor sport during ‘extreme heat’ conditions.
3. What is Heat Illness?
Heat illness in sport manifests itself as heat exhaustion, or the
more severe heat stroke, both of which have possible dire
consequences due to the loss of normal functioning and skill.
Symptoms for both are characterised by:
o
High heat rate,
o
Light headedness, dizziness
o
Headaches
o
Loss of endurance, skill/clumsiness
or unsteadiness,
o
Confusion,
o
Nausea,
o
Aggressive or irrational behaviour,
o
Collapse
o
Ashen pale grey skin
Any driver or official showing signs of confusion, loss of skill,
co-ordination etc. should be stopped and removed from the event and
medical attention should be sought immediately.
4. Hydration & Diet
Plain water is generally considered to be the most appropriate fluid
to drink however in the unlikely event of extreme or chronic
dehydration, some sodium based drinks may be beneficial.
Insufficient hydration before, during and after an event can lead to
dehydration which can make a driver more susceptible to fatigue and
reduction in performance which highlights not only a safety risk to
the driver but to all other competitors and officials at the event.
Therefore adequate hydration PRIOR TO COMPETITION is the easiest and
simplest manner in which a person can overcome dehydration.
Do not wait until you feel thirsty before you drink as thirst is an
indicator that you are already becoming dehydrated.
5. Expert Information.
Please note: these are direct quotes from the organisations noted.
They may not be entirely appropriate for your particular area of
participation in motor sport and should be considered to be used as
a guide.
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FIA |
SPORTS MEDICINE AUSTRALIA – SA BRANCH |
AUSTRALIAN INSTITUTE OF SPORT |
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NB: these
recommendations, originally intended for F1 drivers taking
part in Grands Prix (2 hours of intense physical & mental
stress in high temperatures), should be adapted to the type
of activity concerned.
“The loss of
liquid through sweating can reach between 0.5 & 1 ltr per hr
of driving, depending on the subject & the outside
temperature. This loss may lead to a notable reduction in
the performances of drivers & greatly jeopardise their
safety”. |
NB: these
recommendations were prepared based on ‘athletic’ based
sports. Consideration must also be given to cabin
temperatures and climatic conditions inclusive of
environmental i.e. location – say Indy 500 factors include
enclosed track – concrete buildings on all sides, bitumen
etc. exacerbates heat.
Dehydration will
make an athlete more susceptible to fatigue & muscle cramps.
Inadequate fluid replacement fluid replacement before,
during & after exercise will lead to excessive dehydration,
which may lead to heat exhaustion &/or heat stroke.
Even small
degrees of dehydration can cause a decrease in exercise
performance:
o
Physical & mental performance deteriorates at even 2% of
body weight loss (e.g. 1.5kg for a 75kg person).
o
If
you lose 5% of your body weight (e.g. 3.5kg for a 70kg
person) then serious heat injury can occur.
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A document was
put together in 2004 by a AIS Dietician, CAMS Senior Sports
Development Officer & Sports Dieticians Australia based on
V8 Supercars (as I understand it for the development camps
held in Canberra).
“Dehydration of
1.5-2% (1.1-1.5kg for a 75kg driver) can significantly
affect both physical & mental performance. Hot cabin
conditions are exacerbated by the triple layered fire-proof
suit, fireproof underwear, gloves, socks, helmet and boots
that drivers must wear. In long races, fluid losses are
likely to be very high. Studies of relatively short races
with Supercar drivers in hot conditions show cabin
temperatures above 50o C, with average sweat
losses resulting in a 3% loss of bodyweight. To offset large
losses of fluid that are likely to occur in the race,
drivers need to have a plan for hydration.”
o
Drink sufficiently in the days leading up to the race to
maintain hydration. Aim to drink with all meals & snacks
throughout the day. In hotter conditions, additional drinks
between meals may be required. |
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How Much Fluid do
I Need?
You can assess
how much fluid you need by weighing your self before & after
an event.
o
1kg
lost = 1 ltr fluid deficit
o
2kg
lost = 2 ltrs fluid deficit etc.
o
Sweating & fluid loss continues after exercise. Aim to
replace at least 1.5 times the amount of fluid deficit,
measured at the end of exercise.
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How much fluid do
I need?
Drink 400-600ml
of fluid 2-3 hrs before the race, providing adequate time to
urinate any excess. |
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What to Drink
For races of 2
hrs or less, non-aerated water is recommended. With water,
fruit juice may also be drunk.
Hydration
Routine:
Up to 5 ltrs of
liquid may be consumed on the day of the race, depending on
climatic conditions:
- 1ltr in the
morning before the race
- 2 ltrs during
the race
- 2 ltrs after
the race |
What to Drink
Although water
replaces fluids, sports drinks (containing 4-8% carbohydrate
& small amounts of electrolytes) provide:
o
Additional energy from carbohydrate which can delay fatigue
& enhance performance, especially during prolonged events
o
Salts (electrolytes) which aid the rehydration process.
o
Even if you do not need the extra fuel, flavoured drinks
such as sports drinks encourage fluid consumption more than
plain water, and therefore lead to improved fluid balance.
Hydration
Routine:
o
Athletes drink approx. 500ml (2 glasses) in the 2 hrs prior
to exercise.
o
Athletes exercising for more than 60mins 500-700ml (2-3
glasses) of cool water or sports drink. This should be
sufficient for most types of exercise.
o
After exercise, fluid deficits should be replenished to
ensure athlete is rehydrated and not over-hydrated.
However “Drink
Up’ Brochure says:
o
Drink at least 500ml (2-3 glasses) ½ to 1 hr prior to
exercise.
o
Drink at least 200ml (1 glass) every 10-15mions during
exercise.
o
After exercise drink 11/2 times your fluid
deficit to ensure you are fully rehydrated. |
What to Drink
Ideally, choose a
fluid that contains sodium (sports drink) or consume this
drink with some food.
Hydration
Routine:
o
Drink 400-600ml of fluid 2-3hrs before the race, providing
adequate time to urinate any excess.
o
Drink 200-300ml of fluid immediately before the race.
o
Use
a fluid delivery system to drink regularly throughout the
race. Ideally you should determine a plan based on your
usual fluid losses.
Fluid loss can
usually be determined by pre and post event body weight.
Each kg of weight loss is equivalent to 1 ltr of fluid loss.
Begin drinking
early in the race and in small amounts, to ensure your fluid
intake matches your fluid loss.
o
Using the pre & post body weight rationale will help
determine quantity – however generally drivers will need to
drink 150% of any post race fluid deficit.
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To be Avoided
-
Aerated drinks
- Coffee, tea,
depending on the sensitivity of the individual.
- Large
quantities of fruits
- Large amounts
of confectionary.
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Recommended:
- Non-aerated
water, fruit juice energy drinks
- Sugars absorbed
slowly (pasta, rice, bread)
- Food absorbed
quickly & with a high calorific value (dried fruit) |
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Recommended:
A drink which
contains sodium e.g. sports drink.
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Suggested Menu
for the Day of the Race
Breakfast:
Large. Drink as much as desired, in small quantities.
Before the Race:
a
small meal if necessary, e.g. bread, cheese, ham, mixed
salad or even pasta, 1 piece of fruit, include a few
biscuits.
Drinks:
about 1
ltr, in split quantities (2/3 water, max. 1/3 fruit juice),
spread over the 2 hrs before the race.
During the Race:
it
is desirable, depending on the duration of the race, to fit
a liquid dispensing device, the quantity of liquid to be
consumed during the race being 1 ltr of water which can be
mixed with low-sugar fruit juice (less than 25gr. per ltr),
or an energy drink.
After the Race:
drink plenty of liquid. The addition of a little salt to
food to compensate for any loss. A quarter ltr of fruit
juice replaces the quantity of mineral salts lost in 2 to 3
ltrs of perspiration, that is to say, the maximum lost
during the race. Tomato juice has the same properties.
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Suggested
selections Prior to an Event
o
To
ensure food is digested prior to competition, eat a meal
2-4hrs before or a lighter snack 1-2hrs before competing.
o
Choose carbohydrate-rich foods that are low in fat to avoid
abdominal discomfort .e.g. Plain pasta & tomato sauce, white
toast & jam, low fat creamed rice, plain breakfast cereal &
skim milk.
o
Choose foods you are familiar with & plan ahead.
After an Event
Consume a
carbohydrate-rich drink or snack immediately after exercise
particularly if there is a short recovery time between
sessions.
Nutritious
carbohydrate foods that also contain moderate amounts of
protein may help recovery by speeding muscle repair &
assisting immune function.
Continue to drink
until fluid deficit is replaced.
There is an
example of snack foods for recovery listed if feels
necessary.
Generally, a
meal that is carbohydrate based, with moderate protein and
provides additional nutrients is recommended.
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Suggested
Selections:
2-3 hrs prior to
race:
Generally, a meal
that is carbohydrate based, with moderate protein and
provides additional nutrients is recommended.
1-2 hrs prior to
race:
A light snack can
be consumed prior to race based on individual choices.
Drivers who suffer from nerves or poor appetite prior to
racing may find liquid meals or a series of smaller snacks
more suitable than a meal.
Breakfast:
Cereal, toast & juice, Baked beans on toast & juice, Fruit
salad & yoghurt, poached or scrambled eggs on toast plus
fruit, crumpets and a banana smoothie, pancakes with fruit &
yoghurt.
Lunch:
Sandwiches & juice, pasta with low-fat sauce & fruit, home
made pizza with low-fat toppings, rice or noodle dishes,
home made burgers.
Snacks:
Sports
drink, juice, fruit, sandwiches, yoghurt, cereal bars,
packer soup & bread, hot chocolate & marshmallows in hot
environs.
Suggestions for
those who can’t eat a
Solid Meal
Pre-Race:
Smoothie
with your favourite fruit, liquid meal drink (PowerBar
Protein Plus, Sustagen Sport), a banana juice and a couple
of cereal bars, sports bar (PowerBar Performance Bar) and
sports drink.
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6. Environmental Factors
Obvious as it may sound, the major factor which leads to heat
illness is the temperature on the day! ‘Normal’ temperatures vary
from state to state so therefore it is difficult to place arbitrary
limits on what temperature should be chosen in order to undertake
extra preparation for protection against the possibility of heat
illness. It is suggested that if a persons duties will place them in
a situation where their normal environmental temperature is
increased significantly, then preparation against heat illness is
recommended.
7. Duration &
Intensity of an Event
The combination of extreme environmental conditions and sustained
vigorous exercise is particularly hazardous. The greater the
intensity and duration, the greater the risk.
By way of example, cabin temperatures in race and rally vehicles,
in hot ambient conditions have been shown to reach up to 60 degrees
C. Studies of relatively short races with V8 Supercar drivers in hot
conditions show cabin temperatures above 50 degrees C, with average
sweat losses resulting in 3% loss of bodyweight.
In such conditions, extra attention to the benefits of
appropriate hydration is considered to be essential to the continued
well being of participants.
8. Local
Environment
Radiant heat from surfaces such as black asphalt and or concrete
can exacerbate hot weather conditions. When such an external
environment, together with a relatively ‘enclosed environment’, e.g.
a street circuit such as the Clipsal 500, and also when coupled with
the enclosed interior environment of a race or rally car, is
considered, it is easy to see how the intensity of heat can be
dramatically increased (over that which exists on a relatively cool
day).
CAMS recommends as good practice that at all events, comments on
hydration should form part of the drivers/officials briefing.
The FIA has recognised both the
issue of dehydration as well as high temperatures in the cockpit as
being worth of further comment.
On the issue of dehydration a
document which was drawn up in 1982 by the French doctors Richelet
and Bertrand has been adapted and included into the Drivers Safety
Guide of the FIA Institute of Motor Sport Safety (exerts of which
are shown in the table above (on pages 2,3 & 4), and are in draft
format).
The issue of cabin temperatures has also been
addressed by the FIA. Upon further investigation by the FIA Closed
Car Research Group, concluded that in a hot environment, the maximum
recommended body temperature (39o C) can be reached after
only 40 minutes of racing but was not specifically related to the
wearing of heat/ flame resistant long underwear. For events taking
place in extreme heat, the FIA recommended that a cooling system be
used (connected, for example, to the underwear designed for such
purpose) which has been homologated to FIA Standard 8856-2000.
Substances which may circulate in any cooling
system worn by a driver are restricted to water, or air at
atmospheric pressure. Water systems must not require the saturation
of a garment in order to function (as per Minutes of the FIA Safety
Commission Meeting held on 19 October 2005).
Adequate airflow in cars should be considered as it decreases
heat stress.
Any persons who may be affected by drugs or alcohol are also
possibly at extreme risk of heat illness.
9. Specific information for
Officials
Officials are often exposed to the possibility of heat illness
not only by the temperature of the day but by factors such as:
·
Length of exposure.
·
Intensity of the sun (UV Index).
·
Physical intensity required by their task.
There are a number of OH&S & Worksafe guidelines for employees
working outdoors and in hot conditions which it is considered are
appropriate for officials who perform ‘trackside’ or ‘stage side’
duties.
The following suggestions may assist to reduce the onset and effects
of heat illness.
·
Provision of rest breaks.
·
Provision of adequate supplies of cool drinking water.
It is suggested that the consumption of 100-200ml of water at
frequent intervals is of benefit.
·
Provision of shade.
·
Provision of suitable personal protection equipment
e.g. wide brimmed hat with neck guard, sunscreen, sunglasses
·
Spray bottles.
·
Rotation of officials e.g. changing of tasks at point
where possible and practical without causing disruption to the
event.
·
Removal of personal protective equipment (balaclavas,
heavy protective clothings etc) when appropriate at events e.g.
between races
·
Wearing of loose clothes may be beneficial.
It is considered that it is the responsibility of the officials
to discuss any concerns they may have with the organiser of the
event.
10. Conclusion
·
Heat illness can be significantly
reduced or prevented by the simple action of consumption (drinking)
of adequate amounts of appropriate fluid (water) prior to, during
and after competition or officiating duties.
·
The risk of heat illness is
significantly greater when participants are exposed to an
environment where they experience hotter conditions than they are
used to.
·
Such conditions may be exacerbated
by not only heat increase, but by the length of time undertaking a
task, length of time in an unprotected (non-shaded) environment and
lack of cool drinking water.
·
The most effective way of reducing
the risk of heat illness is to drink adequate amounts of appropriate
fluid (water) before an activity.
·
The hotter the day; the more
exposure to a heated environment; the longer you are ‘at a task’,
the greater the amount of fluids which should be consumed is
necessary.
References and
further information
www.ais.org.au/nutrition/HotTopics.asp
www.sma.org.au/information/resources.asp
www.smartplay.com.au/national/doclib/xpub/docliball
www.sportdieticians.com
www.ais.org.au/nutrition/documents/FactFluid.pdf
Document
Name: IP Hot weather participation
Date of
Issue: 20 November
2006
Contact:
Leanne Glascott
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