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Today’s Health Upgrade
Like blood doping…but legal
The anti-frailty diet
The problem with most protein bars
The brain fog breaker
Arnold’s Podcast
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On Our Radar
How To Boost Endurance Like You’re Blood Doping
File this one under — it sounds too crazy to be true…but it might be true.
Researchers explored how holding your breath underwater before your workout can affect performance. The protocol might sound weird, but the results were surprising.
Scientists found that holding your breath under water before a workout can delay fatigue and improve endurance.
It’s not the pre-workout routine you imagine, but the odd technique enhances your body's oxygen utilization, similar to what blood doping accomplishes.
Scientists have been studying how breath improves performance. When you hold your breath underwater, it triggers the “mammalian diving reflex.” That’s a fancy way of saying your body goes into “don’t die” mode, blood flow and oxygen changes, your heart rate slows down, and your spleen stores extra red blood cells to give you oxygen when needed.
In blood doping, athletes will inject themselves with extra red blood cells, which allows them to have more oxygen to their muscles, which can help improve endurance and aerobic capacity.
When you hold your breath underwater, your spleen provides extra oxygen, giving you a workout boost, such as improving VO2 max.
Other research has identified ways that breathwork can help, but it hasn’t unlocked the same performance benefits of blood doping — until this new study added a twist.
The participants held their breath while dunking their heads into cold water (not your typical pre-workout routine). They did this five times, and each time, they performed a cycling test. The average across all 5 “reps” of submersion was 70 seconds, but — even after the first breath hold (which lasted an average of 40 seconds) — the participants experienced a small but significant improvement in their performance.
Participants saw increased red blood cells, indicating improved oxygen-carrying capacity and the muscles used oxygen more efficiently. Not only that, but it took longer for fatigue to kick in, and there was a shift suggesting improved aerobic metabolism.
Pre-exercise breath-holding may enhance endurance by increasing the circulation of reserve red blood cells and improving oxygen delivery to muscles. These findings could be particularly beneficial for athletes seeking to optimize performance without relying on supplements or other interventions.
Now, this was just one study. And, dunking your head underwater for a minute isn’t necessarily as safe — or as practical — as pre-loading some caffeine. So, why did we share?
Because even though more research is needed, it hints at the power of breath. Learning how to manage your fatigue and your breath — even without going for a pre-workout dunk — could help you push yourself a little harder and prevent premature fatigue.
Nutrition
The Anti-Frailty Diet
Protein might be having its moment, but it’s not the only food that plays a role in longevity.
New research found that certain fruits and vegetables might help fight frailty, keeping you younger and less likely to experience a sharp decline as you age.
The study spanned 15 years and analyzed the dietary habits of more than 40,000 people.
The scientists found that citrus, melons, berries, and dark green vegetables can significantly lower your risk of frailty.
Foods with vibrant colors (like berries, citrus, and leafy greens) are high in antioxidants like vitamin C, beta-carotene, and polyphenols and loaded with vitamins and minerals like potassium, magnesium, and vitamin K. These compounds combat oxidative stress and inflammation, both of which are linked to muscle weakness, poor mobility, and frailty. They also have unique phytochemicals (e.g., flavonoids) that support cellular health, improve circulation, and may enhance physical performance.
If you struggle to eat enough, sneak fruits and vegetables into meals you love. Make a protein smoothie with a serving of fruit and two handfuls of spinach to cover two daily servings. Try soups or sauces, sneak vegetables into eggs and sandwiches, and find ways to add what you need to your favorite foods.
Together With David
The Problem With Most Protein Bars
Protein bars are a convenient option, but let’s be honest: Most protein bars are marketing masquerading as nutrition.
Here are four reasons we tend to limit or stay away from protein bars:
Low protein: Many bars don’t even hit the 20-gram mark needed for muscle building and recovery.
High sugar: Some have as much – if not more – sugar as a candy bar.
Poor protein quality: Many spike their protein content with incomplete sources, making it look better on the label but worse for your body.
Too many calories: Bars that clock in at 300–400 calories often leave you unsatisfied.
David is different. It’s a protein bar that fixes the flaws of the category while delivering superior nutrition that works for any health goal.
Higher protein: Each bar packs 28 grams of protein—75% of its calories are protein. That’s 50% higher than most protein bars.
Complete amino acid profile: David achieves a perfect 1.0 PDCAAS (Protein Digestibility-Corrected Amino Acid Score) thanks to a blend of high-quality protein sources, making it ideal for muscle building and overall health.
No wasted calories: With just 150 calories and 0 grams of sugar, David helps you hit your protein goals without loading up on unnecessary fillers.
Whether you’re traveling, need an on-the-go option, or struggle to get enough protein in your diet, David delivers everything you need and nothing you don’t. This is protein done right.
Mindset
The Brain Fog Breaker
Feeling stuck at work? Instead of powering through, try a less is more approach. Research shows it’s one of the simplest ways to recharge your brain and boost productivity.
Research suggests a quick, intentional break every few hours can clear brain fog, reduce mental fatigue, and spark creativity.
The secret is that the break should be shorter than you think and happen more often than you might be comfortable with.
If you want to boost work well-being and productivity, all you need is a 10-minute break. But, it’s important to take a few per day, not going more than 2 to 3 hours without a short mental refresh.
While hustle culture gets all the attention, your brain isn’t wired to stay in overdrive. Innovative ideas often surface when you let your mind wander—it’s why your best thoughts might come in the shower or during a workout. Breaks create the space for fresh insights to emerge.
And there’s another thing to remember: what you do during your break matters. Scrolling social media? Not so helpful—it’s mentally draining. Instead, step outside for fresh air, watch something funny, listen to your favorite song, or dive into a hobby. These activities are proven to refresh your focus and energy.
Taking breaks isn’t slacking—it’s working smarter. Try building a few into your day and see how much more you accomplish. You’ll feel better, think clearer, and burn out less.
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Publisher: Arnold Schwarzenegger
Editors-in-chief: Adam Bornstein and Daniel Ketchell
