7 Ways MAS Flush Helps Runners Fuel Better

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7 Reasons MAS Flush Helps Runners Fuel Better & Prevents GI Disasters That Derail Your Race

MAS Flush is the only probiotic that contains the specific, research-backed strains that increase glycogen stores by 41%, help you absorb gels 18% faster, and reduce GI distress by 73% so you can fuel your race without your gut fighting back.

You have done everything right. The long runs. The speed work. The days spent dialing in your fueling plan.

But one gel that doesn’t sit right at mile 20 undoes all of your hard work.

And no amount of practicing or switching gel brands will fix this. It is a physiological problem that requires a physiological solution.

The problem is that during the race, blood flow to your digestive system drops by 60 to 70%.

Your stomach essentially shuts down.

The gels you need for fuel just sit there unabsorbed. They either trigger the GI disaster you have been dreading or leave you with nothing in the tank when you need it most.

Luckily, recent research gives us an answer.

Multiple studies show that specific probiotic strains can strengthen the gut lining, improve carbohydrate absorption by 18%, and reduce GI symptoms by 73%.

The catch? Most probiotics are not built for this. They are designed for general digestive health, not for absorbing 60 plus grams of carbs at race pace.

But MAS Flush was formulated exactly for this. Here are 7 ways MAS Flush helps runners fuel better and prevent GI disasters that derail your race.

Gels and other carbohydrates are not efficiently processed in the stomach when racing.

That’s because blood flow to your stomach drops by 60 to 70% when running at marathon pace.

This leads to them sitting in your stomach and pulling water into your intestines, which triggers GI issues and it also means they can’t be used to fuel your muscles.

This is where the probiotics found in MAS Flush change the equation.

In a randomized, placebo-controlled trial, probiotic supplementation increased carbohydrate utilization by a whopping 18%.

This happens because probiotics increase both the abundance and activity of specialized glucose transporters called SGLT1.

These SGLT1 transporters act like toll booth operators, so more transporters working harder means faster processing of the glucose you consume.

This means instead of absorbing 60g of carbs per hour, you absorb closer to 70g.

Over a 4-hour marathon, that is an additional 40g of usable fuel for your muscles that isn’t just sitting in your stomach waiting to cause GI issues.

That is not a marginal gain. That is the difference between a new PR and another race you would rather forget.

0 %

Increase in carbohydrate utilization

0 g

of additional usable fuel for a 4-hour marathoner

Another way to avoid hitting the wall is to simply have more glycogen stored.

The typical runner stores about 300 to 500 grams of usable glycogen in their liver and muscles. That’s enough for about 90 to 120 minutes of running.

The Bifidobacterium longum found in MAS Flush has been shown in research to

Increase glycogen stores in the liver by 33%.
Increase glycogen stores in the muscles by 41%

That means adding MAS Flush to your nutrition arsenal can help you store an extra 200 to 300 grams of usable glycogen on race day.

This is a significant increase and can help you drastically improve performance and reduce the chance of hitting the wall.

Helps produce enzymes that breakdown difficult to digest foods

Reduces the stress placed on the stomach so there is less chance of GI distress

Most runners don’t realize that performance begins to decline well before you’re in danger of hitting the wall.

In fact, studies show that performance begins to deteriorate once the brain senses glycogen stores are at 30 to 35% capacity.

This causes the familiar feeling of heavy legs and decreased motivation that happens late in races that makes it hard to pick up the pace.

However, the probiotics in MAS Flush help increase absorption of the gels you consume, which causes the body to instinctively uses these first, sparing stored muscle glycogen.

This helps prevent reductions in performance that result when the body senses glycogen levels depleting.

No matter what products I tried, I just couldn’t seem to deal with all that sugar. They all tasted okay and seemed to go down okay, but my stomach would always be on the edge of throwing up 20 minutes after. I found MAS Flush from a podcast I listen to and thought maybe it would help. It worked almost right away, I was a little surprised. I’m still cautious, but this seems to have done the trick.

A landmark pair of studies by Pugh et al., demonstrated that supplementing with the specific combination of probiotic strains Bifidobacterium and Lactobacillus significantly reduced the severity, frequency, and duration of GI symptoms during and racing.

The combination works by strengthening the cellular seals between your intestinal cells that break down during hard running due to lack of blood flow and stress.

When those seals fail, endotoxins leak into your bloodstream, triggering the nausea, cramping, and urgency that derail your race.

This is often known as leaky gut.

Runners with elevated endotoxin levels are 4x more likely to experience GI symptoms.

MAS Flush addresses this at the source by strengthening the gut lining to prevent these inflammatory compounds from entering the blood stream.

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The ingredients in MAS Flush don’t just help you fuel better and have less stomach issues, they also directly improve performance by…

Reduced Fatigue Markers (-20-30%) by slowing the build-up of creatine kinase, inflammation and oxidative stress. These are all markers of muscle damage and metabolic stress that contribute to feeling fatigue late in races.
Time to Exhaustion (+37%) by improving metabolic efficiency, which means you can maintain your race pace effort for longer before fatigue limits performance.
Lactate accumulation (-20%) and increased clearance of lactate so you can sustain a higher percentage of your maximum heart rate without reaching the "heavy legs" sensation that causes you to slow down.

Even more directly, researchers at Liverpool John Moores University split marathoners into two groups, one receiving probiotics and the other a placebo.

The probiotic group maintained better running pace in the final 9 miles while the placebo group faded.

Same training. Same course. Different probiotics. Different finish.

This could be the difference between negative-splitting your race and watching your Boston qualifier slip away because you could not keep fueling.

I’ve had some of my best races ruined when I took a gel in the middle of the race and couldn’t seem to keep it down. I wasn’t sure how a probiotic could really help with that, but I gave this a shot anyway. My last two races I haven’t had any issues even though my last race was pretty warm. Feels good to have the confidence I might have kicked this issue.

An often overlooked challenge of racing longer distances is the stress internal and external heat places on the digestive system.

Recent research has identified that when your core temperature reaches 38.5°C (101°F), which happens to 70% of runners during a marathon, intestinal permeability increases.

This further slows the digestive system and significantly increases nausea, stomach pain and GI issues.

Luckily, there is an innovative natural ingredient found in MAS Flush that can mitigate this: New Zealand blackcurrant.

New Zealand blackcurrant extract is rich in anthocyanins and has been shown in research to strengthen the gut lining, mitigating heat stress and improve thermoregulation.

In one study, participants who supplemented with New Zealand blackcurrant for 7 days and then raced in hot conditions experienced a 40% reduction in heat-induced cell damage and “leaky gut”.

In a separate study, blackcurrant was shown to reduce total gastric distress symptoms in runners by 73%.

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Reduction in leaky gut when racing in hot conditions

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total reduction in GI distress symptoms in runners

The fuel you need to train and recover often comes from difficult-to-digest foods such as plant fibers, complex carbohydrates, and proteins.

The endurance-focused digestive enzyme blend found in MAS Flush is specifically designed to help your body naturally digest the foods you need to fuel your training.

These digestive enzymes also improve your gut microbiota to create a more favorable environment in your stomach.

The enzymes in MAS Flush have been shown in research to…

Help you break down food and extract nutrients, making it easier for the body to absorb.
Improve the integrity of the gut lining, which helps prevent the leakage of undigested food particles (often called leaky gut) and enhances nutrient absorption.
Reduce gut inflammation to increase the absorption of micronutrients like calcium and iron.
Cultivate and prime virus fighting cells so your body is more capable of fending off the increased chances of getting sick that accompanies hard training.

This means MAS Flush supports your performance every day, not just on race day.

What Does This Mean For Your Spring Training?

Give Yourself Every Advantage on Race Day & Don’t Leave Fueling and Stomach Issues to Chance.

You’ve just learned how MAS Flush tackles the exact stomach, absorption, and fueling challenges that derail so many runners.

Not just in theory, but in real, research-tested physiology that matters on race day.

The question is not whether you can run the race without addressing these challenges. The question is whether you want to leave it to chance.

Think about what a preventable GI disaster actually costs you.

Not just the race itself, but the 16 weeks of training that led to it.

The early mornings, the long runs, the workouts you pushed through when you did not feel like it.

All of that preparation, compromised by a problem that could have been addressed weeks earlier.

That is the real cost of not doing everything you can to fuel better and stop GI issues before they start.

20% OFF for a Limited Time

Take advantage of our Spring race training sale before it’s too late.

513+ Athletes Trust MAS Flush

Try it risk-free for your training block with our 90-Day Moneyback Guarantee

Hundreds Have Experienced Real Relief, Peace of Mind and Results

I tried this product during the beta launch because I really struggled with stomach pain when racing and even after hard workouts. There were times after hard workouts that it would take hours for my stomach to feel normal. MAS Flush changed everything. I’ve been using it for a month and I haven’t had any stomach pain after workouts. I’m so glad I found this.

Gels gave me horrible stomach cramps on three different occasions so I was desperate to try anything. I used Flush on every long run for my build up for Chicago and had no issues. Race day was the first marathon I had where my stomach wasn’t churning in the final miles. Really happy I found this!

How to use MAS Flush

MAS Flush isn’t just a race day hack...it’s a fueling strategy that supports every phase of your training.

Remember that probiotics aren’t a magic pill. Research shows that probiotic benefits begin after about 2-4 weeks of supplementation.

That’s because it takes time to clear out bad bacteria and heal your stomach so you can train, race and fuel better.

The sooner you start, the more time you give your gut to adapt.

7- 14 Days

The probiotics in MAS Flush go to work healing your gut.

Remove the toxic bacteria in your gut
Begin healing the gut lining to prevent endotoxins entering.
Start making bathroom visits more consistent

2 Weeks

Fewer GI issues& better digestion

Practically eliminates the potential for runner's trots
Better digestion and absorption of the foods you eat.
Less stomach and GI issues after hard, strenuous workouts.

Week 3

You'll begin to notice you're more fueled for workouts.

Stored glycogen levels begin to increase
You can consume more gels and fluids during training runs.

Week 4

Ready to hit the starting line fully fueled and ready to race your best.

Your stomach is prepared for the challenge of running hard
Experience fewer GI issues late in the race and on warm days.
Better absorption of the gels you need to fuel your race.

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