Preparation & Hydration
Last post we talked about how our bodies can adapt to these conditions. Acclimatization is not a silver bullet, so we must also prepare our body everyday. Alcohol, illicit drugs, and some supplements may increase our risk of heat susceptibility. So we must make smart nutritional choices and couple them with great recovery behavior.
The average person will require 1.5 liters of water a day to sustain physiological function. (Letner C., 1981) by that token, hydration should be continuous and should never involve what is referred to as “forced hydration”. Typically you should be consuming a small amount of water continuously throughout your day to avoid symptoms of dehydration. Which is considered severe when a loss of 3% body weight occurs due to sweating. (Kolka et al., 2003) The US Navy and Marine Corps use urine color as an indication of hydration status.
- Clear lightly colored urine in large volumes will indicated a proper level of hydration,
- Dark colored urine, with strong smell, and low volume will indicate a need to consume fluids.
- Marines are recommended to begin hydration 24-48 hours before heavy physical training that will last for extended periods of time. (NMPM, 2009)
For a more detailed suggestion, the American College of Sports Medicine recommends drinking, SLOWLY, 5-7 ml/kg of body weight 4 hours prior to your training session. If you do not produce urine or have dark colored urine, then consume 3-5 ml/kg per body weight for the next 2 hours. (Stand P., 1996) Being properly hydrated prior to training will be your best bet, while we do exercise at a high intensity, the length of time actually training is relatively low.
More is not better in terms of hydration. During exercise we may find a need to consume water, but excessive drinking can lead to a life threatening condition known as HYPONATREMIA which causes swelling of the tissues surrounding the brain. This condition is otherwise know as water intoxication which stems from drinking large amounts of water coupled with a large loss of sodium (salt). This creates an imbalance in the way your cells retain salt and water. This condition is rare; essentially, any workout under 15 minutes will likely not require large amounts of water intake.
(1) Avoid stimulants and diuretics, while research is not 100% conclusive on their effect during exercise, if you don’t normally take something don’t experiment with it during an excessively hot day.
(2) Get a full night of restful sleep, Navy standard is 6 hours and National Athletic Trainers’ Association is 7 hours, so lets call it a solid 8 hours of sleep to be at our best.
(3) Ensure that you are properly hydrated every day, utilizing the guidelines above.
Do I consume more than 36oz of water each day?
More than 64oz?
More than 128oz?