As we are constantly reminded by sports clinicians, nutritionists and physicians abut the importance of water, forever telling us the vital importance of staying hydrated, we can’t help but wonder why. What are you selling? In fact not going back to far in the annals of exercise and sports history the relevance of water was viewed as not very important. Even up to 30 years ago in pure marathon not only was drinking fluids frowned upon, but it was considered as a form of cheating! In the 1970’s, research came to prove that not only are the appropriate fluids exceedingly important in the view of maximum performance, but also in the prevention of serious illness caused from dehydration and other heat disorders.
Even at 5% dehydration we see a decrease in exercise and work performance especially in those with a history of heart disease. For the athlete and working individuals remember the body’s natural thirst response does not kick in until after you are dehydrated. If you are thirsty, it’s already too late. In fact, during prolonged activity the body can lose up to 1 to 2 litres per hour! This equates to 2 to 4 lbs. of body weight. Here is the problem: for every litre lost the heart must work 8-10 beats more per minute than it normally would. The healthy or worse, diseased heart consequently receives 1 litre less blood per minute to power your working body.
This in when we see the resultant Heat Cramps or perhaps Heat Syncope (passing out) or Heat Exhaustion (elevated heart rates, cease to sweat, fatal in the elderly or those with heart disease) or to the worst degree, Heat Stroke (fatal even if treated). All these causes are exacerbated in the unfit.
Ideally consuming fluids at the same rate as you are losing them would be the greatest plan. If you weigh yourself before and after working or training outdoors and weight lost will be from fluids. Replenish them!
Do not start hot weather work down in fluids. Decide what you are going to drink. Some sport drinks have proven effective in prevention of dehydration and also improve performance in exercise or work lasting more than 1 hour. Start to drink 15-20 minutes before the event.
After the event or long day in the hay, drink until you feel all the fluids have been replaced. Use your weight as a gauge.