HSC PDHPE – CQ3 DP3 CQ3 – What role do preventative actions play in enhancing the wellbeing of the athlete?

What role do preventative actions play in enhancing the wellbeing of the athlete? Students learn about: Students learn to: environmental considerations temperature regulation (convection, radiation, conduction, evaporation) climatic conditions (temperature, humidity, wind, rain, altitude, pollution) guidelines for fluid intake acclimatisation evaluate strategies an athlete could employ to support the body’s temperature regulation mechanisms   analyse the impact of climatic conditions on safe sports participation

3. environmental considerations

3. environmental considerations

3. environmental considerations The environment in which an athlete trains or competes has a significant impact on their body’s ability to perform well. High or low environmental temperatures can have a significant impact on the body’s physiological structures, as the body tries to adapt and maintain its core body temperature (thermoregulation). Participating in particularly harsh environments, such as in snow or extreme heat, careful regulation of core body temperature is vital for the body to function effectively.

temperature regulation (convection, radiation, conduction, evaporation)

temperature regulation (convection, radiation, conduction, evaporation) The ability of the body to control its temperature is called thermoregulation. Major changes in the core temperature of the body can be extremely dangerous. Thermoregulation is achieved in the following ways: convection, radiation, conduction and evaporation.

convection Convection refers to moving currents of air. Body temperature is influenced by the flow of air across the skin, as in the cooling experienced from a fan. Cyclists gain a cooling effect through convection. In cold climates, strong air currents are a serious threat. This is commonly known as ‘wind chill’. If the air currents are warmer than body temperature, the body will gain heat.

convection

radiation Radiation describes the gain of heat from and loss of heat to the surrounding atmosphere. The body will lose heat when the atmosphere is cooler than the body; for example, in an air- conditioned room. The body will increase in temperature when the atmosphere is warmer than the body; for example, in a sauna or on a hot tennis court.

radiation

conduction Thermoregulation by conduction involves skin contact with an object of a different temperature. The body will lose temperature when in contact with a colder surface; for example, ice packs, snow, wet clothing or cold water. Conversely, the body will increase in temperature when in contact with a warmer surface; for example, a hot road, warm water or an electric blanket.

conduction

evaporation As sweat evaporates from the skin, a cooling effect is achieved, thus releasing heat from the body. Evaporation is the most important avenue for heat loss from the body.

evaporation

climatic conditions (temperature, humidity, wind, rain, altitude, pollution)

climatic conditions (temperature, humidity, wind, rain, altitude, pollution) The climate can also have an impact on sporting performance. With the use of a range of preventative strategies and actions most negative impacts can be minimised.

climatic conditions (temperature, humidity, wind, rain) Air temperature and humidity are vital factors in thermoregulation. If the air is dry and a breeze is blowing, sweat can easily evaporate off the skin. In these circumstances, the body’s cooling system works efficiently. If humid and sunny conditions prevail, however, sweat does not evaporate as readily. Sweat drips off the body, and the cooling effect is reduced. When air temperatures reach above 25°C, caution is needed when exercising. If air temperature is high, especially if accompanied by high humidity, more serious health problems can result, particularly when endurance performance is required.

climatic conditions (temperature, humidity, wind, rain) Because the body’s temperature-regulation mechanisms, particularly evaporation, might not function effectively in hot and humid conditions, hyperthermia can result. Hyperthermia is a serious condition in which the core body temperature has risen dangerously high. It is characterised by confusion, hot skin, headache, nausea and, in severe cases, collapse and coma. Urgent medical treatment is required.

climatic conditions (temperature, humidity, wind, rain)

climatic conditions (temperature, humidity, wind, rain) Establishing the wet-bulb globe temperature (WBGT) is useful when determining humidity levels. This measure is used at events such as the Australian Open Tennis in Melbourne. Problems can also occur when engaging in physical activity in cold and windy climates. If air temperature is cold, strong wind currents can contribute to the ‘wind-chill factor’. If appropriate insulating clothing is not available, this can produce a life-threatening situation. Extremely low core body temperature is called hypothermia.

climatic conditions (temperature, humidity, wind, rain)

climatic conditions (temperature, humidity, wind, rain) Being exposed to cold water for a prolonged time also poses a serious health risk. Compared with air, water is a more efficient conductor. The body thus loses heat more quickly when immersed in water. Immersion hypothermia can occur when the body is immersed in cold water for an extended time. Both hypothermia and hyperthermia are more likely to occur when there is a combination of extreme climatic conditions—heat and humidity (hyperthermia), or cold and wind (hypothermia).

climatic conditions (temperature, humidity, wind, rain)

climatic conditions (altitude) Exercising at altitude can also affect the well- being of an athlete. Millions of people live with no apparent difficulty at altitudes greater than 3000 metres above sea level. They are able to work and exercise comfortably because they are accustomed, or acclimatised, to the conditions. At altitudes of around 1500 metres above sea level the ability to perform physical work is affected; and the higher the altitude the more severe the effect.

climatic conditions (altitude) Short-term anaerobic work is not affected by altitude, but longer-term aerobic performances are diminished in high altitude. This is due to hypoxia, which is a condition where an inadequate supply of oxygen is available to the body. At higher altitudes, atmospheric pressure decreases. The air is less dense; that is, each litre of air contains fewer molecules of oxygen. In technical terms, this is described as a lower partial pressure of oxygen. In this situation, a person would require more air in order to obtain the same amount of oxygen as would be obtained at sea level.

climatic conditions (altitude) Max VO2 decreases with increasing altitude. Up to moderate altitudes (less than 4000 metres) this is believed to be due to a decrease in the arterial oxygen content, because of a decrease in oxygen partial pressure. At higher altitudes, the decrease is explained by a decrease in cardiac output. Lower humidity and air temperatures at altitude also create temperature-regulation problems in the body. It is recommended that athletes who need to perform at higher altitudes undergo acclimatisation to altitude to promote their well-being.

climatic conditions (pollution) The effects of air pollution on the well-being and performance of athletes can be viewed as detrimental. Few studies have been undertaken to determine these effects, however, and so many scientists remain unsure of the exact effects of air pollution. Lung function is particularly affected by air pollution. The pollutant carbon monoxide (found in car exhaust fumes) potentially reduces the delivery of oxygen to working muscles, which depend on oxygen to function efficiently. Polluted air inflames and irritates the respiratory system, which triggers asthma attacks, and high levels of pollutants can lead to respiratory illnesses.

climatic conditions (pollution)

guidelines for fluid intake

guidelines for fluid intake Exercise leads to fluid loss. Maintaining hydration levels is important to the well-being of participants in physical activity. Thirst is a poor indicator of when fluid should be consumed. When we are thirsty we are well on the way to dehydration. If not hydrated adequately participants run the risk of becoming dehydrated.

guidelines for fluid intake

guidelines for fluid intake Dehydration impedes performance, contributes to fatigue and can lead to other heat-related illnesses, such as heat stress and heat stroke. Water is an excellent source of fluid replacement. Consumption of sports drinks containing carbohydrates and electrolytes should be considered in endurance-style events.

acclimatisation The hypoxia produced at altitude stimulates physiological adaptations that improve tolerance of the changed conditions, both at rest and during exercise. This process, by which the body adapts to the effects of altitude, is called acclimatisation.

acclimatisation The immediate responses to exercising at altitude are: hyperventilation (increased ventilation) — occurs within a few hours upon arrival at higher altitude, and stabilises after about one week increased cardiac output — due to changes in heart rate, not stroke volume (that is, the heart beats faster, rather than each beat pushing out more blood) increased blood pressure.

acclimatisation The longer-term adjustments involve: increase in the number of red blood cells and haemoglobin (in the first weeks) re-establishment of the acid-base (pH) balance of body fluids (in the first few days) changes to tissues and cells (after some time).

acclimatisation The longer someone stays at high altitude the better the person’s performance becomes. When athletes who normally train or compete at sea level go to a higher altitude they will usually spend some time acclimatising before competing. The number of weeks spent acclimatising depends on the altitude. It is best done as a gradual process, with the athletes progressively moving to higher altitudes only when they feel comfortable to do so.

acclimatisation For the first few days at altitude (above 3000 metres) many people will suffer from ‘mountain sickness’. This usually results from ascending too quickly, rather than acclimatising gradually. Some people never acclimatise and continue to suffer from mountain sickness at altitude. Symptoms of mountain sickness include headache, nausea, vomiting, loss of appetite, loss of vision and insomnia.

acclimatisation https://www.youtube.com/watch?v=i0wxmsPDN08

acclimatisation Descent to lower altitudes will help, but if the person remains at high altitude and the illness continues, even light exercise can be intolerable. The person may experience pneumonia-like signs and symptoms, such as breathing difficulties, headache and loss of appetite. In some cases, the disease can be fatal.

acclimatisation Most people do not suffer extreme difficulties and instead gradually acclimatise. The benefits of acclimatisation are lost within 2–3 weeks after returning to sea level. Acclimatisation will not solve all the problems associated with exercising at altitude. For example, max VO2 will increase for some people, and decrease for others, after training at altitude.

acclimatisation Many people believe that training at altitude can improve aerobic performance at sea level. This claim has not been fully supported by research. Some athletes show improvements, whereas others do not. The main problem is that the intensity required to improve aerobic capacity at sea level cannot be comfortably maintained at altitude.