1 billion people on our planet are deficient in Vitamin D

Is that even possible? Being the geeky person I am, and even though I’ve been hearing about Vitamin D deficiency for years, I was still quite skeptical about this, so I dug a little: it turns out that there is plenty of evidence to support this claim!

Not 1, not 10, but dozens of studies over the past decades indicate that us Homo Sapiens have been becoming more and more deficient in Vitamin D over the past decades, with deficiencies currently at there peak.

But still, I was skeptical, and asked myself a few questions and set out trying to answer them:

• Who actually determines the level below which we are “deficient”?
• So what if we are deficient? We would see a lot of sick people if it is true that 1 billion people are deficient and if that deficiency presents hazards to our health and well-being.
•  What changed? Were human beings always deficient or is it a new phenomenon caused by our “way of life” in the 20^th and 21^st century?
• What are the symptoms of deficiency? What are the risks?
• And what can we do to remedy the situation?

Before I get started, a small disclaimer: while I did major in Biology and Physiology as a pre-med in college (BS in Biology), I am NOT a medical professional and my opinions are based purely on my education, my avid interest in all things health, medical and fitness related, and my ongoing studies in physiology and nutrition. Please do NOT take my writings as medical advice and seek a qualified medical practitioner for sound medical guidance.

Throughout this blog, you will see some paragraphs written in Italic. These indicate a “nerd alert!!!!” where I dig a little deeper into certain aspects. Those paragraphs can be skipped entirely without losing much to be honest!

Ok, here we go:

So what is Vitamin D and why should you care about it?

You see there are 2 types of vitamins: water soluble ones (such as Vitamins B and C) and fat soluble ones (such as Vitamin D, A, E and K).

Another major difference between them is that most of the Vitamin D that you need can actually be manufactured (technically synthesized) by your body. In fact, if you were to rely purely on ingested vitamin D (from foods or supplements), you’d pretty much have to eat oily fish and pop dozens of pills daily, not fun, sustainable, or healthy.

For the sake of simplicity, I’ll use the term VitD to refer to Vitamin D as well as its active and inactive derivatives and precursors.

Funny enough, VitD is not classified by the FDS as an “essential dietary vitamin”. The reason for that is NOT because it is not essential, but because the classification takes into account the fact the it can be synthesized by the body on its own.

Of course if the body is not capable of doing that adequately (due to limited sun exposure for example), then we’re in trouble and we have to get it from somewhere else.

We’ll come back to how your body manufactures this vitamin, but let’s talk a bit more about what it is and what it does first:

VitD is essentially a steroid hormone. Well technically, it’s a secosteroid, which is a molecule similar to a steroid molecule except that 2 of the carbon atom rings are “broken”.

The term Vitamin D generally refers to numerous forms of this steroid, but 2 forms are the most important for human being: ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3). Vitamin D2 is synthesized by plants. Vitamin D3 is synthesized by humans in the skin when it is exposed to sunlight.

Most of the active forms of VitD in the body are derived from Vitamin D3.

So what’s the big deal about VitD?

Hundreds of studies have been done on the functions of VitD and what we know is staggering:

• VitD regulates over 1000 different genes in the human body!
• Almost every cell in the human body has a VitD receptor! (not shocking given that VitD is a hormone and most cells have hormone receptors, but still…
• VitD is critical for bone health (density and mineralization):

VitD is a primary regulator of calcium (C) and phosphate (PO₄) homeostatis; it regulates the absorption of Ca and PO₄ in the intestinal tract and consequently its availability in the blood stream and to muscles and bones. It also indirectly regulates the rate of resorption in bone as well as the parathyroid hormone. Note that it is not the only regulator, but a primary one – other factors come into play.

Please contact me for additional readings on calcium sufficiency and supplementation.

• Low levels of VitD have been associated with increased mortality
• Numerous studies support the hypothesis that VitD deficiency is linked to a number of diseases, including cardiovascular, neuromuscular, metabolic, digestive, and others (more on that later)
• Studies have shown that athletes and active people are at a higher risk of VitD deficiency than others – and many of the early symptoms of VitD deficiency (e.g. lethargy, muscle weakness) are incorrectly attributed to low iron levels – please see section below on VitD and Athletes

Below is a table in which I summarize the diseases and disorders linked to VitD deficiency:

DISEASES & DISORDERS RELATED TO VITAMIN D DEFICIENCY
Name of Disease	Disease Details	Scientific Evidence
Familial hypophosphatemia	Bone deformation in children caused by low phosphate levels	Strong
Fanconi syndrome hypophosphatemia	Kidney disease	Strong
Hyperparathyroidism	Overactive parathyroid glands regulating Calcium and Phosphate	Strong
Osteomalacia	Softening of bone and muscle weakness in adults	Strong
Psoriasis	Severe skin disorder	Strong
Rickets	Weakness and deformity in bones among children	Strong
Falls in Elderly	Evidence of VitD reducing incidence of falls among elderly	Good
Muscle weakness/pain	Evidence of VitD reducing muscle weakness among adults & children	Good
Osteoporosis	Reduced bone density and fragility in adults	Good
Asthma	VitD observed to reduce symptoms	Observed
Autoimmune diseases	VitD found to have anti-inflammatory and immunomodulating effects	Observed
Cancer prevention	Studies indicate inverse association btw VitD and colorectal, cervical, breast, and prostate cancers	Observed
Cardiovascular disease	Observed relationship with increased CVD occurences	Observed
Cognition	Better cognitive test results among elderly with VitD supplementation	Observed
Hypertension	Observed: low VitD levels linked to higher blood pressure	Observed
Mood Disorders	Low VitD linked to depression and PMS	Observed
Multiple sclerosis	Lower MS rates in greater sunlight and higher consumption of vitD rich fish	Observed
Type 2 diabetes	VitD shown to improve insulin sensitivity	Observed
Source: www.mayoclinic.com

So what level is considered “Deficient”

Well unfortunately, that’s not very clear. While dozens of studies have been done and conclusions have been reached that lower levels of circulating VitD can lead to numerous problems as listed above, there is no consensus on a threshold or range.

There are however some general guidelines put forward by a number of credible sources. Here is what is considered “sufficient”:

• The Vitamin D Council: 40-80ng/ml (based on over 1,000 studies reviewed)
• The US Endocrine Society: 30-100ng/ml
• The Food and Nutrition Board: >20ng/ml
• General laboratories: 40-100ng/ml
• Australian Family Physician journal: >40ng/ml

According to the Archives of Internal Medicine, over 70% of Americans have been found to have levels of circulating VitD below 30ng/ml, classifying them as deficient. (this study was published in 2009 and based on samples take between 2001 and 2004, but there are no indications that levels have recovered during the past 10 years).

(At the end of this blog, you will find a couple of additional examples of studies showing the correlation of low levels of VitD with certain disorders).

So did we like “wake up one day and realize we’re deficient”??

Well, not really.

Of course it’s hard to tell whether people before the 20^th century were deficient, but the data available to us suggests that we’ve been becoming increasingly deficient since the 1950s, decade after decade.

It’s hard to correlate that to specific phenomena, but obviously the human race went through a revolution of some sorts after World War II with a big acceleration in urbanization and industrialization. 

Here are some of the trends which could have contributed to increased deficiency in VitD:

• We collectively spend a lot less time outdoors
• The “scare” around skin cancer has caused an explosion in sun-screen products
• Our average “work week” has increased (in terms of number of hours)
• The frequency and duration of “vacations” have dropped
• The general nutrient-density of our diet has deteriorated (quality of foods we consume)
• Metabolic (obesity, diabetes) and digestive disorders are on the rise, increasing the demand for vitamins and minerals in our bodies

Ok, but that’s for the general population, what about us “athletes”?

Well there are 2 things to be considered here:

1. Are athletes generally more or less likely to be deficient?
2. Does VitD deficiency (and supplementation) impact performance?

Regarding question 1:

• Willis et al found in 2008 that 77% of German gymnasts had VitD levels below 35 ng/ml and 37% had levels below 10 ng/ml (clearly deficient)

• In study published in 2006 by the International Journal of Sports Medicine, the average VitD levels for cyclists in France was found to be 32ng/ml. This is surprising for a sport with so much sun exposure!

In my personal opinion, the increased metabolic and mineral demands in athletes justify an even higher threshold of minimum circulating levels of VitD.

I mean think about it: our bones are stressed, our muscles are stressed, we lose calcium and other minerals through sweating and metabolic needs and repair, and we are in a constant state of “inflammation”.

All of these factors justify the need for a higher minimum level of VitD than the average population to ensure proper calcium and phosphate absorption, bone density and mineralization, optimal digesting and endocrine function and reduced inflammation!

Regarding question 2 (performance):

An article published in May 2009 of the Journal of Medicine and Science in Sports and Exercise highlights observations from numerous studies:

• Positive relationship between UV-induced Vitamin D and athletic performance
• Physical and athletic performance is seasonal: peaking during high-UV periods and declines when UV-exposure declines
• VitD increases size and number of fast twitch fibers in muscles
• Improvement in athletic performance observed when levels go above 50ng/mL
• Longer recovery needed between workouts for athletes with lower VitD levels

There are also some seen but yet untested observations that low levels of VitD impact VO2max, so there you go! Who wants that!?

There are also some observations where VitD supplementation has been seen to reduce inflammation (faster recovery) due to lower cytokines and better production of anti-inflammatory cytokines. Again without getting too geeky, citokines are a group of hormone-like proteins and glycoproteins whose function is to regulate the body’s response to inflammation, infection, and other disorders.

BUT and it’s a big BUT: studies have shown that these positive effects only impact people who are deficient in VitD, and that “extra” supplementation in VitD if you are not deficient does NOT enhance performance (sorry to disappoint) - here that Lance?.

So how does our body manufacture VitD anyway?

According to the Journal of Nutrition (2003), between 10,000-20,000 International Units (IU) of VitD can be synthesized by human skin from 30min of UV exposure (sunlight).  

In fact, our skin uses a derivative of the existing cholesterol from our bloodstream to synthesize VitD - and that’s another side benefit ;-).

But that's something to keep in mind too: with the big scare around cholesterol levels, there are many people walking around on cholesterol medication who have artificially depressed levels of cholesterol. This doesn't just impact VitD production, but a wide array of cholesterol-derived hormones, such as testosterone.

Without getting too geeky about translating what this production means in terms of our daily needs, suffice it to say that this kind of sun exposure is sufficient to provide 90% of the daily needs for us humans.

HOWEVER:

• This assumes that we get 30min of exposure DAILY

• This assumes the quality of sunshine we get is good: i.e. that UV rays are not blocked by smog, pollution etc

• Sunscreen (even SPF8) will block UV rays and reduce VitD production by up to 95%!

• However burned skin from too much sun exposure has a similar effect: the skin would be so damaged that VitD production is almost completely impaired

• Glass partially blocks UV rays, so sitting behind a window does NOT count

• This assumes that our skin is “fair”: for really tanned people and individuals with darker skin, longer exposure would be needed as the darker the skin, the less UV rays reach the levels of the skin needed to activate synthesis of VitD

Note on sunscreen: there are some supplements (taken orally) that enhance your skin’s ability to protect you from the sun, which would still allow you to synthesize VitD from UV exposure without increasing the risk of melanoma (skin cancer). Contact me if you’re interested in finding out more.

hmmmm, but we live in Dubai, where’s it’s practically sunny year-round, so do we need to worry about this?

Well in my personal opinion, we absolutely must worry about this, and here is my reasoning as to why:

• We spend the vast majority of our time indoors or behind glass windows
• We (endurance athletes) tend to train either very early in the morning or late at night, and therefore we do not get optimal UV exposure
• Let’s face it: many days in Dubai suffer from smog/humidity/pollution, all of which significantly filter our the UV rays we need

Yeah ok fine, so what do we do about it?

Sucking on those UV Rays:

Well, tricky question: I could tell you to go sit in the sun for 30min every day, but that’s hardly a practical solution for any of us right? And even then, that’s what’s recommended for the average person – you would need more as an athlete. But then sitting in the sun for 60min without sunscreen brings on other risks: sunburn, melanoma (skin cancer), etc.

(in fact, technically, the optimal exposure timeframe is between 10:00am and 3:00pm as that is when UV rays have the optimal wavelengths, again hardly a practical solution for most).

Yeah so no, that doesn’t work.

For those who can afford the time and expense, you can however use a sunbed for 10min. There is evidence out there from a number of studies showing that exposure to UV rays from sunbeds are just as good at triggering VitD synthesis in the body as UV rays from sunlight. Also, such rays are more concentrated, so you need less exposure vs. sitting in the sun.

Ok what about Vitamin-D-rich foods?

Well again sorry to burst your bubble but there are no “Vitamin D-rich foods” per se. There are some which have more than others, and there are some “VitD fortified” products (if you’re into such products). But neither really help significantly in remedying a deficiency.

As a guideline:

• Vitamin D2: very hard to find in foods. There is some evidence pointing to Vitamin D2 synthesis in certain types of mushrooms when exposed to UV light, but I doubt that any of us are going to pick up a box of button mushrooms from Spinney’s and leave it outdoors (let me know if you attempt that J)

• Vitamin D3: fish liver oils, fatty fish (salmon, sardines, etc), eggs, beef liver – industrially manufactured Vitamin D3 is sometimes added to certain fortified products such as bread, milk, juices, etc.

Oh, and one more important thing about this topic:

• VitD is a “fat soluble vitamin”, so people with certain disorders such as Chrones Disease, Cystic Fibrosis, and Coeliac are at an even higher risk of VitD deficiency due to their impaired ability to metabolize fat.

Great, more pills to pop!!

Afraid so…

Outside of sitting in the sun, the only way to get sufficient VitD is through supplementation, and the best of the products out there is Vitamin D3: it is more readily absorbable and, in its existing form, it is more readily available to be “activated” in the body and start performing a number of functions related to bone health, immune system health, metabolic activity, etc.

So how much to take? Well there is no clear consensus once again, but here are some general guidelines:

• Vitamin D Council: 5,000 IU/day
• Endocrine Society: 2,000 IU/day
• Ben Greenfield (fitness guru): 5,000 IU/day
• FDA: 600 IU/day (but then again, typically all of their recommendations are quite low)

I personally take 4,000 IU per day split over 2 doses.

A couple of comments about these guidelines:

• These are recommendations for the general population, so I don’t see a risk with athletes abiding by them
• These recommendations are for “maintenance” of adequate VitD levels, and chances are we are all deficient – so it will take a while before we “replenish”
• Given the increased demands on our bodies from endurance training, I would suggest to combine supplementation with frequent exposure to UV (either sun or sunbeds)
• There are some liquid (spray) forms of Vitamin D3, which is more rapidly absorbed sublingually (under the tongue) when compared to pills/capsules which need to be digested

Too much of a good thing?

Healthcare professionals rarely advise people against “taking too many vitamins”. The reason for that is that most vitamins are water-soluble. In other words, your body will use what it needs and will get rid of the excess through urine.

HOWEVER, VitD is a “fat-soluble” vitamin. This means that you cannot excrete it through urine, and your body will have a hard time disposing of excess levels. (It’s an even bigger risk with fat-soluble Vitamin A).

Having said that, it’s “really hard” to reach such a level of VitD concentration where it becomes dangerous (technically it’s not the VitD concentration that’s dangerous but the associated increase in calcium concentration in the blood).

• Your body’s primary way of regulating VitD will be by reducing the synthesis of VitD in the skin – and since 90% of your VitD is produced by the skin, that plays a big factor in regulating concentration
• Studies have shown that it takes 20,000 IU to induce toxicity in rats, 3 million IU to be fatal in dogs! You do the math! Untested data point towards 600,000 IU to reach toxic levels in humans (trust me, that’s a lot of pills!)
• Both the Vitamin D Council and the Endocrine Society set upper limits at 10,000 IU per day (for an average 400 IU VitD pill, that’s 25 pills!)

ADDITIONAL READINGS

UK study January 2009 on 1414 caucasian females

• Significant correlation between levels of VitD and (i) sunbed exposure and (ii) long holidays in sunny climates. Higher correlation for holidays vs. sunbed exposure
• Negative relationship between sunburn and levels of VitD. Sunburned people tend to have lower VitD (body unable to synthesize VitD from UV rays)
• Positive correlation between tanned skin and VitD levels in Caucasians
• Studies have shown that overall Vitamin D levels are lower among ethnic groups with darker skin (e.g. African and Sub-Continent) but this does not neccesarily affect bone-health: studies have shown that African-American women have higher bone density due to other genetic factors
• Studies have shown higher incidence of osteoporosis among women in North Europe and UK vs. Southern Europe

August 2012 published 10-year observation of 9146 individuals in Denmark

• Significant correlation between VitD levels and death caused by certain diseases:
• Respiratory diseases
• Digestive diseases (e.g. liver and kidney disease)
• Endocrine diseases
• Nutritional and metabolic diseases (e.g. obesity, diabetes)
• Cancer
• Cardiovascular diseases
• Mental disorders (e.g. dementia, depression)
• VitD essential regulator of Calcium homeostatis and bone minerlization – it is hormonally active
• It is metabolized in the liver and kidneys to its active form, a steroid hormone

Physically active children better academic achievers?

Interesting new study showing a clear improvement in cognitive function in children (age <10) when physically active compared to regular non-active studying.

http://www.plosone.org/article/info:doi/10.1371/journal.pone.0072666

My thoughts:
- Study clearly shows that active children outperform non-active children regardless of study method
- It would be interesting to explore the relationship between "level" of activity and "cognitive function" - this would allow us to provide feedback to schools and parents as to whether school-based activities are sufficient?
- With the ongoing epidemic of childhood obesity globally (and especially in the GCC), I would like to work with groups willing to actively engage with schools and communities in the UAE to encourage physical activity in children

Tony

The Injury Cycle

This was originally published on June 2, 2013

A couple of days ago, I was sought for advice by a fellow triathlete:

After 4 years injury-free, he's come down with multiple injuries over the past 4 months. This has lead to frustration, forced training leading to more injuries, and a loss of love for the sport.

I sat down with him and went over his training, life etc. By the end of the conversation, the answers were clear to me:

- That athlete got into triathlon at a "relaxed" time of his life: comfortable job, with good pay and decent hours, no kids

- He's been training between 15 and 20 hours a week for 3 years, with no problems

- Over the past year, he changed jobs into a much more demanding role, had a baby, and increased his travel frequency

- He wanted to stick to his training schedule. With life and work demanding more hours, he started cutting corners: less sleep, less body maintenance, etc.

- He would pile on the stress when a workout was missed or delayed

So, something had to give, the body and mind just said: enough! I need a break, and since you're not giving it to me, I'll make you... and the injuries started coming...

---------

For newcomers and experienced athletes alike, dealing with burnout and injuries is probably the most frustrating experience in endurance training and racing. But it does not need to be the case.

Very few among us are genetically gifted with resilient bodies that can take a pounding day in and day out and remain injury fee. 

Professional athletes have the advantage of time: they allocate most of their day to recovery and treatment of any biomechanical inefficiencies. They also benefit from being surrounded by sports medicine and therapeutic professionals.

Most amateur endurance athletes have full-time jobs, family responsibilities, and daily stress. These things conspire against us and increase the risk of fatigue and injury when training and racing. It could be as simple as sitting in an office chair for hours, leading to compression of the spine, weakness in neck muscles, etc. 

If such increased risk factors are ignored when training, we expose ourselves to the risk of overloading these areas, pushing them to the point of injury.

The result? We end up in a continuous cycle of: train - get injured - stop training - recover - train - get injured, etc. A very frustrating experience I've heard only too often (and experienced myself when I first got started in triathlon).

While consistency is an endurance athlete's best friend, such a boom-bust cycle is its worst enemy.

This is one of the main reasons why I strive to get to know my athletes well beyond the training: I need to familiarize myself with their daily lives, home requirements, work demands and conditions, history of injuries or weaknesses, etc. I then integrate all of that input into the training program, rather than forcing a rigid training schedule onto life.

A successful athlete is one who arrives at the race fit, race-ready, and fresh / injury free.

Don't fret! You will be training hard, sometimes quite hard, but you'll also recover well and let your body and mind absorb all of that training, getting ready for the next round!

Take a look at the link below, it presents an interesting illustration of the injury cycle.

http://www.tptherapy.com/unlock-your-body-injury-cycle.html

Train smart!

Tony

Hydration for hot weather training

Update dated: 24 April 2014

It's been almost a year since I published the article below, and I've done a lot more research as well as a lot more experimentation since. When you read my conclusions and recommendations at the bottom of this blog post, please bear in mind these "new" views:

Electrolytes

I've come to the conclusion that it's virtually impossible to completely deplete yourself of minerals during a single training session or single-day race. I've raced an Ironman without electrolytes, I trained through the summer without electrolytes, and I raced the scorching hot Abu Dhabi Tri in March (report here) again with no electrolytes, and I never suffered any cramping issues whatsoever.

Cramps
I've done a ton of research on cellular biochemistry and behavior among athletes, I've experimented on myself extensively, and I observed athletes I work with even more extensively, and I'm firming up my opinion on causes of muscle cramps in endurance sports, ranked by order of incidence: (i) dehydration, (ii) muscle fatigue (iii) Glycolysis.

(i) Dehydration: as I explained in last year's post below, dehydration may be caused by insufficient water intake and / or stomach contents having a high concentration of dissolved solids (e.g. electrolytes or food, gels, etc).

(ii) Muscle Fatigue: of course the obvious one would be insufficient training. However I think the more overlooked aspect is rather insufficient event-specific training: if you've trained "long and slow" for months (along with appropriate nutrition), you are likely to have developed a good fat-burning metabolism and an abundance of slowtwitch muscle fibers. 

But if you never incorporated much strength training and / or speed/tempo work into your training, your muscles are likely to have relatively low numbers of fast-twitch fibers. 
No matter how hard we try, we always push "a little extra" in races, regardless of distance. The higher the intensity, the more fast-twitch muscle fibers we're recruiting. If we haven't trained to adapt to the specific demands of a race, the effort is likely to overwhelm and exhaust our relatively fewer fast-twitch fibers pretty quickly. 

Furthermore, a lack of sufficient race-specific adaptation in training will also lead to a drop in mitochondrial density within each cell of those fast-twitch fibers: this means that not only do we have an insufficient number of them, but also that the energy being produced by each cell is far below its potential.

Mitochondria are the "power stations" of cells: they produce ATP, the fuel utilized by cells to allow muscle contraction (among other physiological functions).

(iii) Glycolysis: those who train with me know how much I emphasize specificity in training and nutrition: each session is designed to cause a specific adaptation in your body. I've come to realize over the past year that metabolic inefficiency is likely another root cause of cramping among athletes, even at perceived "low intensities" (long-distance triathlon for e.g.). 

Let me try to explain this succinctly without getting too technical: your primary sources of fuel when exercising are fats and glucose (either from stored glycogen or intake of carbohydrates). (I talked extensively about this here). 

As the intensity of the exercise increases, the "choice" of fuel starts shifting from fat towards glucose. Glycolysis (burning of glucose for fuel) results in an increase in the level of acidity in the muscles, and when a certain threshold is reached, the muscle's ability to contract is compromised, causing cramps. (people inaccurately believe that it's the build-up of lactate which causes the cramps - lactate actually helps buffer and lower acidity in muscles, until it's unable to do so anymore and the muscle becomes acidic).

Here's the thing though: the "point at which your body switches from fat to glucose for fuel is different from person to person and can be manipulated through training and nutrition. I will talk extensively about how to go about doing that in my next blog post, but suffice it to say that the less "fat adapted" you are, the "earlier you will switch to glucose along the intensity spectrum", the earlier your muscles will become acidic, and the earlier you will suffer from cramps. 

In other words, a well fat-adapted individual will need to push harder to get into glycolysis and increase muscle acidity, while a non-fat adapted athlete (lower metabolic efficiency) is likely to start building muscle acidity at relatively lower levels of intensity.

The rest of the recommendations in last year's blog post remain valid.

Originally published on Monday, May 6, 2013 at 8:35AMTriDubai

*** thanks to Ian at TriDubai for the graphics! ***

I went for a run a few nights ago and could barely keep my heart rate under control:  the Dubai summer is officially here:  heat, humidity, smog, and the perils of air conditioning.

This coincides with a number of questions I've received recently from beginner as well as "elite" amateur endurance athletes regarding the optimal nutrition and hydration strategy for hot weather training.

After all, who among us hasn't suffered through heat-induced cramps, stomach problems, bloating, and bonking when training / racing in the sandpit summer?  I know I have! And I still make mistakes with that...

Let me start with a small reminder from basic school biology: do you remember the process of osmosis?  You get 2 liquids, separate them with a membrane.  Add some some salt or any other mineral to one.  So now one of the liquids has a higher concentration of minerals than the other.  As time passes, the "clean" liquid will pass through the membrane into the "concentrated liquid", until both liquids have equal concentration.  How cool is that??!  Ok, now keep that in mind, we'll come back to it later...

Water serves 3 main functions for the endurance athlete:

1.  Temperature regulation

2.  Maintaining cellular chemical balance

3.  Aiding in digestion (to be addressed in separate article)

1.  TEMPERATURE REGULATION

Mechanism:  sweating. Yes, not pleasant, but that's why we can outrun a gazelle over a day-long run...

Sounds simple enough, no?:  When sweating, the water evaporating from the skin cools the skin down, hence cooling the blood in the tiny blood vessels (capillaries) under the skin, and hence cooling the rest of the body.

Not so fast.

This works great in mild and dry weather, where the humidity in the air isn't low.  Remember that school biology lesson we started with about osmosis?  Well when humidity is high, the air is "concentrated" with water molecules, and "doesn't want to take more", this slows down dramatically the evaporation of sweat off your skin. Result:  less cooling.

Your body's reaction:

• Stage 1: uh oh, this sweating thing isn't working very well, let's try and sweat some more --> you start sweating more, so this means losing more and more water, which needs to be replaced

• Stage 2: dammit! Even this higher level of sweating is not cooling me down! That's it! I'm shutting down non-essential units.  HELLO CRAMPS!

This scenario is not uncommon among athletes, even smart ones. They say things like:

• I ran with a fuelbelt and was drinking water all the time!"

• "I took electrolytes all the time" (more on that later)

• But I was still cramping and my heart rate was going through the roof! What's going on??"

Make sure you hydrate properly...

Well, a couple of things are going on:

a.  Yes you're drinking more and more water, which is replacing the sweat you're losing.  So your problem is not getting dehydrated by loss of water.

b.  The water you're drinking from your fuelbelt is warm and getting warmer by the minute by being in the sun/heat and / or close to your body, so effectively you're warming your "insides" with every sip of water, thereby negating any benefits you're getting from sweating.

c.  Yes you're taking electrolytes, which is great since they are essential for your muscles to function, and you're losing them when sweating... but the question is, are you taking too many electrolytes?

This is a good time to talk about how water helps in maintaining your cellular chemical balance.

2. MAINTAINING CELLULAR CHEMICAL BALANCE

a.  Some essential minerals (and water) are needed for our muscles to function properly (won't go into cellular chemistry here, email if you want to know more!).

b.  Those minerals are lost with sweating.

c.  Cells (nervous and muscle fibres) are sensitive to swings in their cellular chemistry (including availability of those minerals).

d.  Replacing those minerals is simple enough: taking electrolytes during hot weather training/racing.

So what could go wrong? Why do athletes suffer from cramps even when taking electrolytes (I'm guilty too, check out my Abu Dhabi race report!!).

Well there are 2 scenarios:

Scenario 1: Not taking any electrolytes

• You sweat, losing water and minerals;

• You drink tons of water to replace sweat;

• Your stomach fills with nice clean water.

RESULT: Remember that osmosis thing?

{water in stomach, low concentration} ==> ||Stomach Wall/Membrane|| ==> {blood, high concentration}

Your stomach wall is the "membrane", on one side you have a "low concentration liquid, the water in your stomach", and on the other you have a "high concentration liquid, your blood".  Because of osmosis, water will move through the stomach wall into your blood stream. This causes your blood to get diluted (becomes lower concentration).

Now you have:

{diluted blood, low concentration} ==> ||Cellular/muscle Wall/Membrane|| ==> {Cells in muscles and nervous system / high concentration}

So what happens now, is water will Flood the cells, diluting the minerals. Cells are now hit with a "double whammy": they're losing minerals from sweating, and the flooding of water is causing whatever minerals are left to get diluted further!  They start shutting down or "mis-firing". HELLO CRAMPS!!!

Ok, so you say, fine, I'll take as much electrolytes as I need. Well yes, but again, not so fast, because there is such a thing as taking TOO MANY electrolytes! It's not easy to keep a balance.

Scenario 2: taking too many electrolytes

• You're smart / experienced enough to know that water alone doesn't work

• You start popping salt tablets like crazy

• Yet you still cramp!!! WTF!!!!???

Well here's "WTF":

Remember that osmosis thing?  Now imagine the situation we have in Scenario 1 above is reversed. You take SO MANY electrolytes that the water in your stomach now is higher in concentration than your blood.

{water in stomach, high concentration} <== ||Stomach Wall/Membrane|| <== {blood, low concentration}

So what do you think happens now?  That's right!: the higher concentration in your stomach is drawing water out of your blood and into your stomach!!! By the same token, now your blood is super concentrated, and draws water out of your cells! and that, ladies and gentlemen, is how one can get dehydrated even when drinking water... when you overload with electrolytes, it's no longer water, it's highly concentrated liquid that's actually pulling water out of your entire body and into your stomach!

Result: cramping, and bloating (ugghh hate that feeling!), liquid sloshing around your stomach... not fun, especially on the run.

CONCLUSION

Well that's all well and good, but what do I do about it??  Well, a solution isn't really a workable solution unless it's simple right? There is no "fool proof" method, but here are my suggestions:

• #TIP1:  Don't overload on salt the days before training / racing. Here's a tidbit: our typical diet (even healthy ones) have 5x to 8x the recommended daily salt intake. AND, our body does store a lot of that.

• #TIP 2:  be careful when taking electrolytes: you want to take in the minimum to maintain osmotic balance. So start with 1 tablet / hr, then increase.  It's a learning process, and eventually you'll find the right balance for you (each body is different).

• #TIP 3: chose a balanced electrolyte: some products out there have way too much salt compared to other minerals.  What happens is that even if you take a tiny bit, and the concentration of minerals in your stomach is "balanced", you will have such a high concentration of "salt" that it creates an osmotic imbalance and draws water out of your blood/cells.

• #TIP 4: be aware of your drinks! Remember, sports drinks (Gatorade, etc) are by design concentrated (due to sugar contents), and by having them in your stomach you're increasing the concentration. If you want to drink them, just be aware of that when taking electrolytes on top. My personal strategy is to drink only water when racing / training - I take my calories and electrolytes separately.

• #TIP 5: drink cold water: whenever you can.  Drinking cold water cools you from the inside, cools your blood and organs.  This is even more critical on humid days where the sweating mechanism isn't doing much to cool you down.

• #TIP 6:  do NOT overhydrate!  On very hot days, it's tempting to guzzle down cold water.  Remember, you need to keep the liquid in your stomach balanced.  Too much water causes an imbalance (see Part 2/Scenario 1 above) - do a "Sweat Test" to determine your sweat rate (call/email for details).

• #TIP 7:  don't forget to hydrate while swimming in the summer.  While you may think that you're not sweating, you are! and you're losing minerals too! So for hard/long swims, replace those lost fluids/minerals

• #TIP 8:  hydration doesn't stop when you stop training. Stay well hydrated throughout your day, before and after training to maintain that infamous osmotic balance...

Happy Training,

T

Article originally appeared on TriDubai - a triathlon club in Dubai (http://www.tridubai.org/).

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