Andy Blow Is At The Forefront Of Sweat Science With Precision Hydration

Today’s guest is Andy Blow and he knows a thing or two about the science of staying hydrated during a run, so stay tuned for some serious sweat talk in today’s episode!

He is a former elite-level triathlete, with several top ten finishes in various Ironman races, and has an Xterra World Title to his name as well.

I am looking forward to trying to keep up with Andy Blow and diving into how he founded Precision Hydration.

Andy Blow

Better Without A Soccer Ball

Andy Blow grew up in the United Kingdom where soccer is the main sport for the majority of the country.

His father was a soccer ref and was struggling to keep up with the players on the field.

At around the age of 40, his dad took up running as a way to get in shape for being a ref.

Andy would often join his father and he quickly realized that he was much better at running when he didn’t have a ball at his feet.

That realization led to Andy joining the cross country team.

Andy had always been a swimmer as well.

In the early ’90s, Andy competed in some swim and run races.

Progression To Triathlons

Andy would eventually progress to competing in triathlons and as it turned out he was quite good.

He took triathlons the most seriously of all the endurance sports that he competed in.

Out of the 3 disciplines, Andy loves running the most and still does that more than the others.

In some ways, cycling and running do complement each other, but in many other ways, they also work directly against each other.

Andy has found that with multi-sport athletes there is always some tension in trying to get the sports to integrate.

In the time period when he had his best results, he was cycling through weeks where he would basically only focus on one discipline at a time.

The idea behind the philosophy was to see if he could make gains in one area while keeping the other areas at a certain level.

Out of the three sports, most injuries occur due to running.

Pushing Through Pain

Andy, like most athletes, has dealt with injuries.

In January of 2020, he tore his calf muscle.

This injury was a result of pushing through pain when he should have listened to his body.

Andy has a strong competitive drive and though it has benefitted him, it has also been what has led to burnout and/or injury.

While studying Sports Science at University, Andy joined an elite performance squad of triathletes.

This team gave him the opportunity to train and compete alongside some Olympic level athletes.

He was about 18 when he got this opportunity and that is when Andy started taking triathlons more seriously.

The Good And The Bad Of Elite-Level Training

During the years that Andy competed at a high level, he experienced first hand both the positive and negative aspects.

Training with teammates that were at a high level enabled him to push himself beyond what he thought was possible.

The flip side is that he often found himself pushing on days that should have been easy.

It is easy to suffer mental and physical burnout if you don’t approach training at a high level appropriately.

What separates the best from almost the best can often be attributed to mental strength.

The best athletes in the world typically have long-term vision and confidence in their ability to achieve that vision.

Raw talent alone will not get someone to the highest level.

Andy noticed a feedback loop where if an athlete performed well, they had more confidence and therefore believed they belonged at the top.

Dreams Vs. Reality

If Andy had his way, he would have made a living as a pro triathlete.

He knew his chances were slim to realize his first dream and he needed a backup plan.

During that time, Andy was working at an internship in the sports science field.

His boss was supportive and encouraged Andy to not give up on his dream.

He made allowances in Andy’s position for him to continue to travel and compete.

During this period is when Andy started to venture into a full Ironman distance.

Andy was able to combine all the sports science he had learned at University with his real-life experience.

Sweat Science

Through his own experiences, Andy had noticed a pattern of repeated failure of performance in hot weather.

In an effort to find a solution, he reached out to a friend that was a heart surgeon to try to gain some insights.

His friend began to break down the physiology of sweating and suggested measuring his salt/sodium loss.

Sweat rate along with sodium loss can vary a lot from person to person.

Andy arranged to have a sweat test done in a hospital and the results were clear.

He was losing more than twice the salt of the average person.

His repeated failure in performance was due to overdrinking and not ingesting enough sodium.

Going forward, Andy started to implement a much more aggressive strategy for replacing salt.

The Magic Bullet

Once Andy tried out his new strategy it was like day and night with his performances.

He was so impressed with the difference that he wanted to include sweat tests at the lab where he worked.

In an effort to do more research with athletes all over the world, he began to converse with others in various athlete forums online.

As he was able to test more people, he realized just how large the ranges of sodium loss were during endurance sports.

Andy was surprised that the science of sweat wasn’t more understood for the common athlete.

This realization led to Andy creating Precision Hydration.

Andy Blow

Precision Hydration

For quite some time, the sports hydration industry only offered one-size-fits-all- products.

Andy knew there was a need for a more individualized hydration approach.

He created a company called Precision Hydration that focused specifically on the best ways to support an athlete’s unique sodium needs.

Along with offering a variety of electrolyte products of various strengths they also have over 200 sweat test machines around the world.

Available on the website is a questionnaire that aids the user in determining how much sweat and sodium they’re losing along with what product may be best.

The website also offers tips on where to start and then from there it’s typically organized trial and error to find the ideal concentration.

Research has shown that an individual doing any activity lasting more than 90 minutes to 2 hours in hot conditions would benefit from electrolytes.

Salt is the electrolyte we lose the most of in sweat.

The Importance Of Salt

Our bodies cannot manufacture sodium in the body, so therefore we must meet our needs by ingesting it.

Most of our sodium needs are met through our diet.

That is typically not the case when it comes to endurance athletes coupled with hot conditions.

More sodium, up to a point, is usually better than less sodium when it comes to performance.

Andy encourages each athlete to experiment with a bit more sodium to find their ideal concentration.

Don’t ignore your body if you’re craving salt, learn to listen to the signals, and interpret them.

Sweat sodium loss is driven largely by genetics.

Risk factors with losing too much sodium increase in heat, but you should still pay attention to sodium consumption year-round.

A Sweat Solution For Everyone

A standard sports drink contains about 400 to 500 mg of sodium per liter.

Precision Hydration offers strengths ranging from 500 mg up to 1,500 mg.

Effervescent tablets and powders are available depending on the athlete’s preference.

The Precision Hydration website offers a variety of options to answer questions.

One on one video calls can be booked through the website if an individual prefers a consult.

Questions can also be sent through email at

Chances are that for most athletes upping their sodium content may positively affect their performance.

Precision Hydration is offering a chance to save 15% by using the code dizruns at checkout.

Mentioned In This Episode:

Stay connected to Andy Blow by following Precision Hydration on FacebookInstagram, and/or Twitter.

Andy Blow a former elite-level triathlete who is the founder of Precision Hydration. He is the expert on all things sweat and staying hydrated is literally his business. Share on X

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2 replies
  1. Marcel
    Marcel says:

    very very interesting. never thought about this in detail. and having tons of question now about my body’s behaviour and its salt consumption. definitively will deep dive into this! thanks.

    • Denny
      Denny says:

      Glad this one got you thinking, Marcel. Definitely something that can make a pretty big difference in performance and in how you feel during/after activity.


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