Environmental Effects on the Body Flashcards
What is a Contemporary example of Environment Effects?
- The Qatar World Cup
- The soaring desert heat meant competition was held within Nov/ Dec and games were played at night to avoid thermal strain
- SYNOPTIC- commercialisation and “Shop Window Effect” for Qatar- large investments into the games
What two factors affect the respiratory and cardiovascular systems the most?
-ALTITIDE AND HUMIDITY
Define altitude?
The height of elevation of an area raised above sea level where there is a lower PARTITAL PRESSURE of oxygen and a decrease in BAROMETRIC PRESSURE
Impacts on the Respiratory System due to Altitude?
-reduction of pp of 02
-decreased rate of diffusion within the alveoli
-decreased saturation of haemoglobin
-decreased transport of 02 to the working muscles
= decreased diffusion into the muscle cell (EXTERNAL RESPIARTION)
-EXPAND= quicker onset of OBLA
=faster lactate build up
=decreased quality of game play
Impacts on Long Distance performers of Altitude?
- decreased VO2 max= reduction in AEROBIC CAPAICTY
- performance of endurance athletes becomes harder= MOTIVATION
- demands of aerobic energy systems increase
- EARLY FATIGUE
“for every 1,000m above sea level, VO2 max drops by around 8-11%”
What is “Hypoxia”?
Altitude Sickness
Define Altitude acclimatisation?
The process whereby an athlete GRADUALLY adopts to a CHANGE in their environment= essential for endurance athletes who rely on 02 transport for effective performance
What are the positive effects of Acclimatisation to altitude?
- release of ETHRYOPOEITIN which increases red blood cell count naturally
- increased 02 transport in the blood = increased consumption in muscle cells
- breathing rate and ventilation stabilise but remain elevated at rest
- SV and Q decrease as 02 transport increases
At what height does altitude start to have an effect?
1,500 m
What are the overall benefits of acclimatisation for CV system and respiratory systems?
Increased RBC count due to increased ERYTHROPOETIN
Breathing rate and frequency can stabilise and remain elevated at rest for a short period
SV and Q reduce as 02 extraction and transport becomes more efficient
Symptoms of Hypoxia/ Altitude Sickness?
- Reduced ability to sleep/ restlessness
- Breathlessness
- Poor sleep
- Lack of appetite
Evaluate Altitude Training?
+increased RBC production due to release of EPO
+increased concentration of haemoglobin
+increased 02 transport
+will last up to 2 weeks = useful pre competition
- expensive to set up due to travel and accommodation
- altitude sickness
- training is tough and requires high levels of MOTIVATION
- LOST FAST
Define Thermoregulation?
The process of maintaining a performers core, internal body temperature
=37 degrees celcius
How does thermoregulation work?
- THERMORECPETORS detect changes to the temp of a performer
- MEDULLA OBLONGATA detects changes to initiate regulation
- Blood is sent to the surface of the skin
- Vasodilation of blood vessels near the skin allows for convection and evaporation of heat
How many litres can an athlete loose of fluid/ hour?
2-3 litres of fluid per hour
What is the effect of dehydration?
Impairs the bodies ability to thermoregulate and core temp will rise
The rate of heat loss through sweat depends on HUMIDITY
LOW HUMIDITY= INCREASED SWEATING
HIGH HUMIDITY= DECREASED SWEATING- sweat has a harder time evaporating into the air
Define humidity?
The amount of water vapour within atmospheric air
Affects the amount of heat lost through sweating
Define Hyperthermia?
An increase in core body temp by SEVERAL degrees Celsius due to an inability to THERMOREGULATE
What three factors cause Hyperthermia?
- High and Prolonged Exercise Intensities
- High Air Temps
- High Relative Humidity
Define CV Drift?
The upward drift in Heart Rate during sustained, steady exercise associated with an increase in body temp
- SV PLATEUS SOONER
- the redistribution of blood flow to the skin for cooling limits the blood flow to the muscles
- rising temp also alters the function of proteins such as ENZYMES= chemical reactions
Effects of CV Drift?
blood plasma decrease
blood viscosity increase
venous return decrease
stroke volume decrease
Effects of CV drift on the Cardiovascular system?
Dilation of arterioles and capillaries increased blood flow and POOLING
Decrease in VR, SV and HR increases to compensate for the STRAIN
Effects of CV Drift on the Reparatory System?
Dehydration and drying of airways= increased mucus production
Increased constriction of the airways
What should a coach do pre- comp and during comp to reduce thermal strain?
ACCLIMATISE TO HEAD- 7-14 days to allow adaptation to heat
-cooling aids-ice vests
Pacing Strategies
Suitable, breathable clothing
ISOTONIC drinks to replace the fluid, glucose and electrolytes of a performer
