Environmental factors affecting Exercise Flashcards
Which system is affected during stressful climates?
Cardiovascular system
How does our body dissipate heat? where does the heat come from?
The heat comes from the metabolism of metabolic fuels to provide energy for our active cells. Blood is then brought to skin transporting the heat to be evaporated to surrounding to dissipate the heat.
Moreover, our body releases water through sweat glands to be evaporated, cooling the body even further.
Does heat increases our heart rate? Why does sweating also cause increased HR?
Yes due to the blood being sent to the skin instead of circulating and returning as venous blood to maintain stroke volume, hence, to increase our cardiac output, HR is needed to increase.
Sweating increases HR due to the same reason, to increase cardiac output. Sweating results in excessive lost of body fluids which results in dehydration which decrease blood volume and thus decreased venous blood.
Why is overhydration as dangerous as dehydration?
Overhydration results in water intoxication which is dilution of sodium and other electrolytes, leading in swelling of the cells including the cells in the brain, hence can lead to life threatening or permanent brain damage conditions.
What causes altitude sickness? How long does it take to get used to altitude?
There is lesser availability of oxygen in the air and lesser pressure to drive oxygen into blood as it passes through the lungs, resulting in lesser oxygenated blood. This leads to altitude sickness which causes headaches and lightheadedness. It takes about 2 weeks to get used to it, but a few months to be fully acclimated.
Why should you avoid exercising in air-polluted areas?
The air pollutants will irritate the airways and decrease the oxygen-carrying capacity of the blood, moreover, it assist in producing cardiac or pulmonary conditions. Prolonged exposure to air pollutants can also lead to ischemia and angina.
How long do we preserve our performance and ability to exercise?
Our ability to perform at high levels can be well preserved into our 30s, however, there is an inevitable decline in performance after 60 regardless of frequent training.
What is the danger behind sedentary middle-aged individuals planning to begin exercise? How do we avoid this danger?
They risk cardiovascular diseases, and triggering myocardial infarction during unaccustomed heavy lifting. To avoid this, they should not do high-intensity training for the first several weeks of exercise as in not exceeding the VT1 threshold and only extending duration not intensity.
