For the Love of Salt!
You are an endurance athlete. You love being out there in all types of
weather for a LONG time! You have your ‘why’ and it fuels you; it gets you
out the door on days you may not always feel like it, but you know you will
feel better when you do. And that is the goal… to feel better when you
come back.
As a former Ironman athlete, I have had my fair share of times when I finished my training feeling depleted. As a Nutritionist who works with many endurance athletes, I have seen many reasons why this happens
including: poor training plans, lack of sleep, lack of calories, lack of water, and lack of sodium. It is the later that is the focus of this article.
Sodium.
Why we need it? How we lose it? How can we replace it? Sodium (Na+) is vital in maintaining body fluids and the proper functioning of muscles and nerves. As an endurance athlete, when your sodium levels
drop, this can affect training and racing results.
When we sweat we lose sodium, in addition to water and the other electrolytes that make up our sweat: potassium, calcium and magnesium. We sweat to help our bodies cool which is why we require more sodium
during our activities when it is hot.
Sweat is brought to the surface of the
skin and then evaporates allowing us to
cool. If you are exercising in a very dry
atmosphere, such as the desert, you
may not realize that you are sweating
as much as you are; your body is effectively cooling as the sweat evaporates. Consider when you train in a humid environment such as Hawaii or Mexico where the cooling effect is not as effective as evaporation is harder. Either way, you are sweating and hence you need to rehydrate with both
water and sodium.
So….why do athletes need it?
Why the focus on Sodium? Other minerals are important but to put it in perspective, in one litre of sweat loss, you can easily lose up to 2000mg of Sodium vs 150mg of potassium. Both during and post workout, sodium can rapidly become a limiting factor in overall performance and recovery. The more one sweats, the more your blood volume is reduced. The liquid portion of sweat comes from interstitial fluid that comes from blood plasma. When you have lower blood volume, your heart has to work harder to get oxygenated blood to your working muscles. Sodium helps maintain blood plasma volume by signalling your kidneys to retain more of the fluid you consume. Consuming only plain water may dilute your blood sodium levels. When this happens, you may find yourself needing to urinate more frequently as the water is not being absorbed and is in essence just flushing through you. Symptoms of low sodium levels also known as hyponatremia include: nausea, vomiting, headache, and fatigue. If not recognized this condition can become very serious resulting in seizures, coma and even death. It is for these reasons it is very important to replenish the sodium that you lose through your sweat.
The amount of sweat one loses is very personal as is the amount of sodium lost. You can do a simple test by weighing yourself pre-training effort and then again post-training effort to get an idea of how much fluid you are losing. One pound lost would be equivalent to 1/2 a litre of fluid.
If you go for a 2 hour run and you lose 6 pounds, this would be water weight you are losing not actual body weight *and the equivalent of 3 litres
of fluid. You can also check out your clothing; the white stains you see is sodium. Sodium on your skin feels sticky. If you get sweat in your eyes and it stings you have a higher amount of sodium in your sweat. Perhaps the best test of all if you are a dog owner is your faithful furry friend thinking you are the best salt lick ever!
If it is very hot (30+ C) even a short 30-60min run can benefit from sodium supplementation. Generally, I like to start with 400mg/hour. The hotter it is, the more you sweat, the saltier your sweat is the more you may need to consume. Up to 1000mg/hour is not unheard of.
I often get asked, “Can I take in too much sodium?”
If you are not sweating, then the answer may be yes. Daily, the average person takes in about 2500-3000mg/day. However, when you are exercising and sweating on a hot day, it becomes much harder hard to get too much sodium.
If you look at fast food such as a burger you will often get over 1500mg just for that burger! Add fries to that you are now over 2000mg for a meal without any exercise. If you tend to eat a diet low in processed foods and you make a lot of your foods from scratch, you will want to consider adding salt to your daily diet. 2500mg is equivalent to a tsp of salt. Consider the differences in salt between canned spaghetti sauce, a can of tomatoes and whole tomatoes from your garden when making a simple pasta dish:
1/2 cup of Paul Newmans Spaghetti sauce = 450mg
1/2 cup of canned diced tomatoes = 200mg
1/2 cup raw tomatoes = 5mg
If you find yourself craving salty foods, you probably need salt! I am a big xc skier in the winter months and yes, I do perspire but nothing like I do in the hot summer months. I also know I don’t crave potato chips (my personal fav is black pepper lime!) In the winter – but Wowza in the summer after a long hot effort – give me a party sized bag please and thank you!
In summary, for the love of salt, add it to your daily diet! During increased physical activity, take sodium either in the form of an electrolyte drink, or take salt tablets. How much you need can vary but practice and start with 400mg/hour and see just how good you can feel. I find that if you cannot taste the salt, it is likely you need it. Have you ever tried an electrolyte drink when you didn’t need it; it tastes super salty and possibly undrinkable. On a hot day, during activity, you don’t even taste the salt and in fact it tastes like the best drink EVER! After training or an event, enjoy salty foods… pickles, crackers, chips, olives, etc., there are so many delicious choices! Allow yourself to be the best you can be with a solid training plan, a good
overall nutrition plan and yes, add sodium!
Happy Trails!
* keep in mind from a body weight perspective 1 pound = 3500calories so
if you were to be losing actual body weight that would be 21000 calories
– NOT likely!!!
Please Note – this article is not intended for people who are dealing with hypertension or on blood pressure medication.
