We get asked all of the time about whether electrolyte replacement (particularly sodium) can help with athletes who get cramp. It is always frustratingly hard to explain why sometimes electrolyte supplementation can be like a complete miracle cure for cramps in certain people, however for others it does not help much at all....

We believe it is likely to be because although electrolytes are implicated in some instances of muscle cramping, many other factors such as fitness level, fatigue and the type of movement patterns being undertaken can also be the cause.

In terms of our own experience in the field with 1000's of athletes we tend to find that a more tailored approach to sodium replacement (with drinks closely matching sweat composition, taken to thirst) reduces incidences of cramping in those who tend to suffer cramping late on in endurance events or in competitive games/matches/tournaments after prolonged periods of sweating. This effect tends to be magnified in hot weather or when intensity is very high, and is more pronounced in athletes with high sweat sodium concentrations and/or very high sweat rates. We have also noted some anecdotal experiences of athletes who used to suffer with cramps when taking in high volumes of plain water or low sodium fluids (because they were scared of becoming dehydrated) - and these athletes often see a reduction in cramping when they have either reduced total fluid intake to more normal levels or taken in additional electrolytes with fluids (or a combination of the two). 

Results with athletes who cramp at seemingly random times tend to be less positive (when using sodium supplements alone) - however programmes of targeted stretching, sports massage, more progressive training overload and general dietary improvement can be helpful in reducing the likelihood of cramping occurring in these individuals.

Because of all this we thought we'd share a review article that does a very good job of explaining the possible links between cramping/fatigue and sodium depletion - and it is well worth a read if you are interested in finding out more about the topic as a whole.

The reference is: 

Bergeron, Michael F. “Muscle Cramps during Exercise V Is It Fatigue or Electrolyte Deficit?” Current Sports Medicine Reports: Supplement-Sodium Balance and Exercise 7.4 (2008)

And the full article can be read of downloaded from this link

A genetic reason for why some people lose more salt in their sweat than others?

We recently came across an interesting study from the USA which offers a very good explanation of why some people are high salt sweaters and others low or normal.  This group in question biopsied the skin of 3 groups of people - those with cystic fibrosis (known to have high levels of sodium and chloride in their sweat), those with high sweat sodium levels but not CF sufferers and those with normal sweat sodium levels.  Those with CF and high salt sweaters had a lower abundance of a protein called cystic fibrosis transmembrane conductance regulator (CFTR).  This protein is responsible for absorption of chloride and sodium in the sweat gland so a lower level means less is absorbed back into the blood and more is excreted out in sweat.  

Ref:

Brown MB.  Low abundance of sweat duct Cl⁻ channel CFTR in both healthy and cystic fibrosis athletes with exceptionally salty sweat during exercise.  Am J Physiol Regul Integr Comp Physiol. 2011; 300: R605–R615

More Evidence For Drinking To Thirst, as well as consuming electrolytes, especially if you lose a lot of salt in your sweat....

Reading Tim Noakes' book "Waterlogged" does make you think hard about whether one should simply respond to their thirst stimulus rather than try to replace lost volume. I generally do agree with this idea (it seems quite a lot of athletes make the mistake of drinking too much pre, during and post exercise) although do disagree with his observation that sweat sodium levels do not very dramatically between humans. There is in fact plenty of evidence that there is a massive variation (infact in a later blog I will describe the genetic basis for the variation that results in lower number abundance of a protein called CFTR).
Just recently while trawling the sea of evidence related to this topic I came across a study done in Georgia, USA in 2011.  The group looked at thirst responses in cystic fibrosis (CF) suffers, non-CF active people with high sweat sodium levels ('salty sweaters') and controls with average sweat sodium levels. After forcefully dehydrating them by 3% of their body weight in a heat chamber they showed that thirst responses were equal across all groups.  They concluded that the thirst mechanism is maintained despite the large variation of sweat sodium losses, blood osmolality and plasma volume between the groups.  They concluded, relevant to our fundamental principle of sweat sodium replacement, that "....sweat Na⁺ losses observed in SS (non CF but high salt sweaters) and CF provide empirical support for models and recommendations for consuming electrolytes during prolonged exercise to guard against the potential for hyponatremia in salty sweaters..."

So in agreement with Noakes, drink to thirst. No matter what your sweat sodium losses your thirst appetite will be preserved.  But drink what you lose.

Dr Raj Jutley. 

Ref: 
Brown MB et al. High-sweat Na⁺ in cystic fibrosis and healthy individuals does not diminish thirst during exercise in the heat.  Am J Physiol Regul Integr Comp Physiol. 2011; 301: R1177–R1185

I would be interested in your thoughts on the lack of need for hydration products as currently proposed by Tim Noakes. He says there is no need for anything like this. He also says that sweat with high levels of sodium are just because of high intakes of sodium and to cut this out also means that the sodium levels in sweat will in turn drop. I went to the talk at all 3 motion and have been using your products and have got on fine so far but I’m wondering if this is placebo or not?

Our response:

Thanks for your email.

It's a very interesting question, one that we're being asked more and more here is our take on it: 

We thought we'd share this one. 

We hear of people using H2Pro Hydrate tablets in some creative ways from time to time; adding them to carbohydrate drinks to boost the sodium content or mixing them in 50/50 with flat coke and water to create a very effective caffeinated, carb drink for racing. But this is definitely the most sophisticated use we've come across so far. 

What's more it's from a very well respected source in the world of nutrition; Barbara Cox, CEO of Nutrichef (who incidentally you can follow on twitter @NutriBarbara), and she's been adding it to her smoothies....Thanks for the heads up on this Barbara....

H2Pro Smoothies:

Dissolve 1 table in 500mls water

Add 1 banana

Add handful of strawberries and blueberries

1 tbsp Chlorella (sea algae for protein)

1 shot wheatgrass juice (I use live frozen wheatgrass shots)

Whizz all together in the blend and voila….gorgeous!

The Patrouille Des Glaciers (PDG) is one of the worlds toughest ski mountaineering races. Held every 2 years in the Alps near Zermatt, Switzerland it is an event with military origins and in 2012 a group of British soldiers headed out to take on the challenge - using H2Pro Hydrate to keep their fluids and electrolytes topped up in a very harsh, unforgiving environment. This is what they had to say about their experience:

"Despite having limited time to prepare we used H2Pro during the flight to Switzerland 48hrs prior to the race which undoubtably helped with our basic hydration. During our training day before the race we tested the race concentration to confirm suitability. Not only did the product keep us hydrated during a long and arduous day but I'm convinced it helped us adjust to the altitude and acclimatise quicker. Although the race was stopped due to avalanches I am sure H2Pro mitigated our lack of environmental training and acclimatisation."

Hydration at high altitude can be an issue due to the dryness of the air and sweat losses whilst ski mountaineering can be very high as it requires a lot of clothing to be worn to protect against the elements yet work rates are very high. Having H2Pro Hydrate in the water they were carrying also helped to stop it freezing up in sub zero temperatures.

We will be supporting the British team in 2 years time when they will get a second chance to take on the PDG - hopefully this time without the avalanche risk that cut this years race short. 

Lee Shannahan with his H2Pro Hydrate and the Matterhorn in the background:

We were interested to read an announcement that someone in the US has created the "ultimate sports drink" with its own spin on the ideal electrolyte mix

The Malaysian Formula 1 GP is considered to be the toughest race on the F1 calendar with the heat and humidity taking its toll on the drivers and race crew. Not surprisingly, according to a recent press release Lucozade prepared a special race formulation drink specific to the Mclaren drivers Button and Hamilton http://paddocktalk.com/news/html/story-186284.  Helen Cowie, Technical Director, GlaxoSmithKline Research & Development admits that '....drivers can lose up to three kilos in sweat – roughly five per cent of their body weight......' But  as the drivers are restricted to 1 litre of drink in the cockpit it is imperative that every drop contributes to performance.  

Although the article is based upon science and supports the basis of what we do at Precision Hydration, it fails to mention that Button and Hamilton (and for that matter every single F1 driver on the start grid) have sweat sodium losses that are genetically determined and vary upto 8-fold. Getting this sodium content in the drink is important as sodium is what determines retention of water in the body.  Bespoke hydration in motorsport is not exclusive to Lucozade either as at Precision Hydration we've been doing it since 2009.  In fact our very first client was an endurance rally driver from Kenya who would typically almost pass out on Day 2 or 3 in the heat despite drinking litres of water.  He was tested using the Precision Hydration sweat sodium analysis system and found to be a very high sodium sweater.  With drinking water alone he would dilute his blood sodium leading to water intoxication (mild hyponatraemia).  On bespoke sodium replacement drinks he is now extremely competitive. Since his success our regular clients include Tuthills Porsche Team, David Brabham (ex-F1 and Le Mans winner) and Bradley Smith in Moto2 as well as numerous drivers in GT racing and rallying where the cockpit temperatures can be incredibly high. 

Taken from the Telegraph 26th March 2012:

Since writing this post the following email landed in my inbox. It seems the Consumer Law Group (CLG) have filed a suit against a coconut water company for making claims that it is a good substitute for a sports drink:

Consumer Law Group files lawsuit against Vita Coco

I felt compelled to post this in response to an article I saw entitled:

DITCH THE SPORTS DRINKS: COCONUT WATER IS NATURES WAY TO REHYDRATE.

See http://frugivoremag.com/2012/03/ditch-the-sports-drink-coconut-water-is-natures-way-to-rehydrate/ 

We're seeing coconut water touted as 'natures electrolyte' more and more often I'm really not sure about this! The article does make some valid observations about the high energy/sugar content of some sports drinks not being needed when you are not training hard but the comments on electrolyte balance are not completely accurate.

While coconut water may be natural I'm not convinced that its the best way to hydrate before, during and after exercise.  For very gentle sessions perhaps it might be ok once in a while but I certainly wouldn't be telling anyone to ditch the sports drinks as recommended by the author.  The article does advise against drinking too much to avoid over-hydration and hyponatraemia (low blood sodium) which it admits can be life-threatening (very true).  However, coconut water typically contains only 160mg sodium per litre which is much less than the average sweat sodium losses in humans of around 920 mg per litre so the issue of hyponatraemia is not really avoided by using it.  Then there's the high potassium content (Potassium is not a bad thing in reasonable quantities in protecting against diabetes and high blood pressure) but one litre of coconut water contains over 60% of your daily potassium requirements.  In long hot events if used as a primary hydrator, even with 3 litres the total potassium load will be 1.8 times the daily requirement plus whatever is taken via sports gels and normal food intake. I use Potassium to stop the heart during cardiac surgery so would be extremely hesitant in advising people to drink large volumes of a potassium rich drink when exercising hard or sweating a lot.

The bottom line is that sodium, not potassium, is the key electrolyte you need to replace when sweating and this is summed up nicely with the quote below:

"The only electrolyte added to drinks consumed during exercise that is known to confer physiological benefit is sodium.”

Report of the Scientific Committee on Food on composition and specification of food intended to meet the expenditure of intense muscular effort, especially for sportsmen. 2001. 

Dr Raj Jutley. CMO Precision Hydration ltd.