How To Optimize Nutrition with Angie Asche

As a sports dietitian working with elite athletes and high-performing executives, Angie Asche has seen the same pattern over and over: people train hard, but are still under-fueled.

In her conversation with WHOOP Global Head of Human Performance, Principal Scientist Dr. Kristen Holmes, Angie Asche explains why eating “less” isn’t the answer, how nutrient timing can make or break your performance, and what truly supports long-term metabolic health.

Why You Might Be Under-Fueled (Even If Your Weight Is Stable)

Most people assume under-fueling only happens when you’re losing weight. Asche disagrees.

“Technically, even if you're maintaining your weight or even if you're gaining weight, you can actually still be under-fueled,” says Asche. “It's really just a matter of that nutrient timing and not fueling your body in key moments when it needs it most.”

Under-fueling isn’t just about how much you eat — it’s about when and what you eat. You can hit your calories by the end of the day and still show up to practice, games, or workouts on empty. 

Common ways high performers end up under-fueled:

• Skipping or skimping on breakfast
• Training fasted or with minimal carbs
• Relying on coffee instead of food
• Eating most calories late at night

Over time, consistent under-fueling can wear down your performance, recovery, and overall health.

The Aesthetics Trap: Leaner Isn’t Always Better

Asche sees a powerful myth in sport and fitness culture: the leaner you are, the better you’ll perform. She describes working with pro-athletes whose sole goal was to get under 10% body fat. 

To get lean, athletes often cut carbs and fat, while keeping protein high. On paper it looked “disciplined.” In reality, they were chronically under-fueled. Instead of a successful season, they felt worse and their performance dipped. 

For female athletes, the cost of under-fueling and low-fat diets can be especially high with risks like: 

• Loss of menstrual cycles
• Hormonal disruption
• Poor bone health risk over time
• Brain fog and mood swings

Asche emphasizes that eating healthy fats and strength training are crucial for women’s overall health.

How Under-Fueling Shows Up in Your Body

Under-fueling doesn’t just leave you hungry. It changes how your body responds to training and stress.

It can cause:

• Higher perceived exertion: The same workout feels much harder
• Persistent fatigue: You’re “gassed” halfway through a long season
• Sleep issues: Trouble falling asleep or staying asleep
• Mood and focus changes: Irritability, brain fog, and poor concentration

WHOOP can help you see this pattern in your own data through lower Recovery, elevated resting heart rate, and lower Sleep Performance when you’re not fueling enough.

Gut Health, Tests, and What Actually Helps

Microbiome and stool tests often end in generic advice: “Eat more fiber, consider a probiotic.”   Asche prefers assessing overall diet quality and basic labs, and tracking how often an athlete gets sick or has GI symptoms.

What she trusts for gut health: 

• A diverse, fiber-rich diet
• Fermented foods like yogurt and kefir
• Strategic probiotics when warranted (e.g., travel, specific GI issues, or under guidance)

Short-Term Performance and Long-Term Metabolic Health 

It’s easy to focus on game day or next week’s race, but Asche also likes to focus on long-term metabolic health.

Her recommendations:  

• Daily movement matters. Consistent walking and everyday activity helps improve insulin sensitivity and overall health.
• Lift something regularly. Muscle acts like a glucose sponge and supports metabolic health as you age.
• Cook more real food. Many people don’t cook because they don’t have the time, but even just thirty minutes of  basic meal prep (chopping veggies, assembling yogurt bowls, prepping grains) can radically improve your diet quality.
• Prioritize fiber. Focus on fruits, vegetables, legumes, whole grains, nuts, and seeds.

With WHOOP, you can zoom out and connect these choices to long-term patterns in your sleep, strain, and recovery — not just how you feel on any one day.

The Bottom Line

Angie Asche’s approach to nutrition is grounded and sustainable: stop holding your performance back, and start fueling to support your body and long-term health. 

The key takeaways: 

• Under-fueling is more common than people think — even in athletes who look strong or maintain their weight. Under-fueling can cause energy, performance, recovery, and sleep to take a hit. 
• Getting carbs and protein in before, during, and after training helps athletes see better energy, recovery, and sleep almost immediately.
• Long-term health isn’t complicated: move daily, incorporate lifting, eat plenty of fiber, and rely less on ultra-processed foods. Small, repeatable choices make the biggest impact over time.

To hear the full conversation and learn more about smarter fueling, tune into the WHOOP podcast.