High-Sugar Fueling: Longevity of the Endurance Athlete under threat?

High-Sugar Fueling: Longevity of the Endurance Athlete under threat?

In his late 60s, Professor Carey Stoneking just became the national 24Hr ultra-running USATF champion, by completing over 93miles. By the way he does it on very little carbs…

Will all endurance athletes be able to deliver a performance like this, when they hit their 60s?

I’m not so sure – and here’s why –

The rise of US triathlon race series in the ’80s was largely bank-rolled by the beverage industry. The leading sports drink of the time ‘ Gatorade’ and Bud-Light Beer were major players.  At that time products like Gatorade were the go to training fuel for athletes in many sports. Within a short time, came many emulators, producing similar products under various ‘…ade’ brands (amazing lack of brand innovation).  By 2014, the leading producers were selling more than 20 billion liters of sports-drinks globally and in the US alone, almost 1 billion liters. In 2016, the leading US sports drink brand earned a cool $3.3 billion dollars revenue (Statistica).

The usage of sports-energy drinks has not only grown beyond consumption by athletes, but they have also evolved from a ‘training-racing fueling product’, to a general consumption drink.  I’ll save my comments on this issue for another day,  but I do want to drill down on the pervasive-frequent use of sports-drinks by competitive endurance athletes – after all, they can be training (and drinking) upto and over 30 hours a week…hence the alarm bells.

At the highest level, endurance athletes are bifurcating between two fueling strategies these days,

A) the heavier carb/protein, little fat group, and,

B) the increasingly the high-fat low carb group.

I won’t go into the pro’s and con’s of each in this article, but suffice to say, the consumption of high-sugar refueling drinks are consumed by group A), and avoided by group B).

OK, so lets first put some context to hydration/fueling practices for your typical ultra endurance athlete.

  • 3-4 training sessions during week days – on average 4-12 hours per week,
  • 1-2 long training sessions on the weekend – on average 4-20 hours on the weekend
  • Typical fluid consumption patterns
    • In temperate/arid climates, fluid consumption in training is ~0.5-1.5 liters/Hour, depending on temperature.
    • In tropical climates, fluid consumption in training can be ~1-2 liters/Hour, depending on temperature

So based on this training load and these typical fluid consumption patterns, its not inconceivable that an athlete could be consuming between 4 and 20 liters of fluid, per week, in training. Now if that was water, with some electrolytes and whole-foods for fueling there would be no concern…but for a vast majority of athletes, this is not the case.

A 500-600ml bottle of sports-drink delivers somewhere between 30-40 grams of sucrose (which is fructose and glucose), the equivalent of around 8-10 teaspoons of crystallized sugar. Therefore, an endurance athlete repeatedly fueling with these drinks could be consuming somewhere between 60 and several hundred teaspoons of sugar in a single week.


Maybe you’re thinking, ‘this isn’t common’. We think you would be surprised just how common it is.  Also note, we’re only calculating the ‘fluid sugars’ here.  The total sugar load maybe even higher when you add high-carb energy bars (30-40grams) and gels (25-30 grams) commonly used.

Now you could write a book, on the broad health implications of all this sugar, but I wanted to focus on some recent research, looking at the consumption of high sugar-drinks  and its association with joint/muscle inflammation.

Published in the Journal of Nutrition and Diabetes last year, researchers found a strong association between joint (and gut) inflammation and arthritis. Prior research has linked the consumption of high-fructose corn syrup to arthritis, but there had not been research looking at the implications of soft drinks and fruit drinks (which generate excess free fructose) on joint/muscle inflammation.

It was found that young adults (20-30years of age) regularly consuming these drinks more than 5 times per week, were 3 times as likely to have arthritic symptoms, vs. non/low consumers.

Think about it for a moment, a 20-30 year old having arthritic symptoms – a condition historically akin to old age. The explanation behind this, was that the inflammation (from fructose/sugars) in the gut, triggered the formation of pro-inflammatory ‘advanced glycation end-products’, which once absorbed, find their way to structural tissues (muscles and joints etc.) to heighten inflammatory symptoms (pain, swelling,  reduced range of movement).

In his book ‘Sugar Crush’, neural surgeon Richard Jacoby walks through his experience and observations of how sugar triggers inflammation, and specifically its role in compression of neural tissue.

I had wondered about this 6 years back, when I began my fuel switch from carbs-sugars and began transitioning to a high-fat/ low-carb fueling approach.  For my longer training runs of 5-8 hours, I would have to take ibuprofen during-after these sessions to deal with the muscle-joint aches and pain.  Well now at 45, I use no anti-inflams in training. I am running faster than I have for 15 years, and without pain.  At the time, I made no connection to sugar-energy-drinks and  the gut formation of pro-inflammatory triggers.


And it’s not just the sugar-glucose that comes through the gut lining, and triggers this inflammation. There is a perfect-storm, where the heightened heat from sustained exercise, degrees of dehydration and simple sugars – particularly fructose that directly breaks-down the integrity of Gut membrane – resulting in liposaccharides (LPS), or endotoxins to enter the blood and further trigger systemic inflammation. We have written one article of the ‘Ultra Gut’, and a second on the Fructose – Maltodextrin concern.

So, coming back to the topic of ‘Longevity’ of the endurance athlete.  I’m going to put it out there, and that is,  I believe the longevity of the endurance athletes lifestyle  is being put at risk by, sugar – period, plain and simple.

In both model research organisms, multiple mammalian models, including human beings – there is a consistent thematic trend that high-calorie, free glucose diets are consistently associated with a shorter life-span. Conversely, calorie restriction, lower carb-sugar load, and physical exercise have shown to be associated with longer lifespans … that would be, longevity.

Now, as so many of us endurance athletes have come to know – this whole endurance thing is way deeper than a weekend recreational sport.  It’s a lifestyle, we value and cherish.  The freedom of running, or swimming or biking through the mountains, or oceans with some degree of ease, is rewarding and satisfying on so many levels. The relief it brings to the stress of life is palpable, and at times fundamentally therapeutic.  So having this ‘part of who we are and how we live’ taken away or shortened – due to pain, or aching muscles-joints and systemic inflammation – isn’t a nice thought.  But it’s happening, and I think it’s happening much more than everyone thinks. Many have  fallen into the trap of blaming ‘age’ to shortening their physically active lifestyles.  Our numerical age is just a number, and our lifestyle and health shouldn’t be dictated by a number.

If you value the lifestyle and state of well-being that endurance sport provides, then be careful and conscious on your fueling practices – here’s our QuickStart Guide to help you along.  How you fuel yourself, in training and racing over the years may very well dictate the longevity of your endurance lifestyle.

Go Longer.  All the best in the longevity of your ultra-lifestyle.

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