Environmental Influences

External factors such as temperature and your own actions can affect the body. Not looking after your body appropriately, particularly in challenging conditions, can cause symptoms such as headaches, lethargy and and nausea. Dehydration, hyponatremia and overtraining are some of the conditions we look at, and we discuss how to identify, treat and prevent them.

Heat Injuries

There are several forms of heat injury which are usually caused by doing exercise in extreme heat or a lack of fluid intake (dehydration). Heat cramps, exhaustion and heat stroke are the most common of these and often invovle dizziness, nausea and headaches. Care should be taken in hot conditions to avoid these problems, with drinking plenty of water and staying out of the sun being key!

Hyponatremia is also known as fluid overload. This occurs in hot climates when the athlete consumes too much plain water. 'Drink as much water as possible' is a common piece of bad advice given to athletes. Topping up sodium levels is just as important as replacing water lost in sweat, as lack of sodium can cause cells to swell. This cen be particularly harmful for brain cells.

Overtraining is excessive high-intensity training and diminished rest periods. This may result in feelings of constant tiredness, reduced performance, neural and hormonal changes, mood swings and frequently poor health. Training too much without enough time to rest and recover can be detrimental and performances may start to suffer. Individuals will often need educating and help to recuperate and get back to full fitness.


Dehydration is an 'excessive loss of water from the body'. This can happen for numerous reasons, such as illness (through vomiting and diarrhea), diseases of the gastrointestinal tract, excessive sweating, and failure to take on a sufficient volume of fluid to replace that which is lost. Being dehydrated causes the blood to thicken which puts excess pressure on the heart and organs.