Engineering Metabolic Health: Dylan Winters on Building a Better Engine, Not Buying Better Fuel

Everybody talks about metabolism. Almost nobody can explain what it actually means for everyday life. In this HatchPath summit, Jordan Dunin sat down with Dylan Winters, Director of Corporate Development at OVAL, the metabolic health platform HatchPath has partnered with to bring science-backed metabolic testing and resources to members. Jordan had just completed his own OVAL test, and what he learned on the bike changed how he trains, how he eats, and how he reads his own body. This is the conversation that closes the gap between the lab and real life.

Fat or Carbs? Start With How the Body Was Designed

The question of whether it is better to burn fat or burn carbs has fueled decades of dietary argument. Dylan's starting point is simpler than the debate: we are designed to use both fuels interchangeably, and we should be able to switch between them based on the demands we are facing.

For sitting in a chair, having a conversation, or taking a light walk, we should be primarily fat utilizing creatures. Carbohydrates are meant for the moments beyond that: intense exercise, fight or flight situations, anything that requires energy right now. The trouble is that as we get older, and as the stresses we are exposed to stack up, that ability to switch becomes reduced. We become more and more dependent on carbohydrates for most things instead of moving freely between the two.

The Fireplace: Fat Is a Log, Carbs Are Paper

Fat is energy dense. It takes longer to convert into the energy currency the body actually uses, which is exactly why it works so well for low demand activity: it is the log on the fireplace that burns low and slow all night.

Carbohydrates are not nearly as energy dense, but the conversion to usable energy is much faster. That is the crumpled piece of paper tossed onto the fire. There is a big plume of flame and then it is gone. When your body says it needs energy now, it leans on carbohydrates, because there is no time to convert fat into fuel. Both systems matter. The problem is when you lose the ability to choose between them.

Your Metabolism Is Your Body's Operating System

Dylan's favorite analogy for metabolism is the operating system on a phone. Whether you carry an Apple or an Android, there is a platform underneath every app you run, and that platform supplies the power. Nutrition, immune function, hormone production, the way your body expresses the genes you carry, the way it communicates with itself: all of these are applications running on your metabolism.

Just like a phone's operating system, yours can become outdated or underpowered over time. You can run the best nutrition app in the world, but if the system underneath it does not have the power to run it, you hit a ceiling quickly. The encouraging part, and the reason Jordan wanted this conversation on the calendar, is that there is a high degree of reversibility to that erosion. You simply cannot see where you stand, or what to do about it, without measuring.

The MetFlex Score: From Guesswork to Strategy

Jordan went through the OVAL test himself before this conversation. On the bike, with an ear prick at each interval, OVAL measures blood lactate to identify exactly where his body switches from burning fat to burning carbs. The result is a MetFlex Index, where MetFlex stands for metabolic flexibility: a single score that says where your metabolic system currently stands.

Jordan scored in the high thirties. The target is above forty. The value of the number is not the number itself, it is what comes with it: individualized guidelines for training and lifestyle that cannot be extrapolated from general advice, because they were measured on you.

For someone who spent a lifetime training to maximum output, the takeaway landed hard. As Jordan put it, the simplest version of the lesson is do more but go less. His coaches had always told him to train until he was tired and then go harder. Science says the opposite: there is a specific zone where the adaptation actually happens, and blowing past it is not effort, it is noise.

Why Harder Is Not Better: The Goldilocks Zone

Dylan uses strength training to make the point. Nobody can hand you an arbitrary weight and expect you to get stronger. It has to be appropriate for your current strength. Too light and your body has no reason to adapt. Too heavy and you either get hurt or simply fail to progress. Metabolic training works the same way, and your test exists to find the weight that is right for you.

The opportunities to improve metabolic health do not live at the high end of your performance capacity. They live in your personalized zone two, positioned near the top of that zone and just beneath zone three, because the stimulus has to be real for the body to respond. The goal is to keep nudging your threshold higher, so your body gets better at burning fat at higher and higher demands.

The First Lactate Threshold

The turning point OVAL looks for is called the first lactate threshold: the point during your test where your power output exceeds your body's ability to keep going without switching fuel sources. Below it, you are primarily burning fat. At it, your body has to move to primarily carbohydrates to meet the new demand. Identify it precisely and you can build heart rate zones that match how your body actually works rather than how a generic formula assumes it works.

Build a Better Engine Instead of Buying Better Fuel

The car metaphor ties the whole conversation together. You can put the finest gasoline in the world into a commuter car, and it will still never behave like a Formula 1 car, because the engine is the limiting factor. The same is true of nutrition. You can eat the cleanest food available, and if your engine cannot process it efficiently, your capacity is capped.

This is where the current wellness conversation tends to stop short. When people talk about metabolism today, they are usually talking about blood sugar responses and making better choices about what goes in. Fuel choice matters. Fuel without engine capacity, however, is only half the project, and it is the half that gets all the attention.

Blood Sugar vs. Lactate: Two Different Signals

A continuous glucose monitor shows you the response to what you already ate. It is a rearview mirror, useful and important, but after the fact. Lactate, measured during the test, tells you where your system switches fuels in real time, which is what makes individualized zones possible in the first place.

OVAL is now developing a continuous version of that measurement. Their strategy for it echoes a familiar playbook: start with a core group of people who genuinely understand the product and believe in it, and grow from there. For everyday people, the promise is compelling. Learn what your body does under high stress, and then build the engine so the same scenario costs you less.

This Applies to Everyone, From Desk Jobs to 100 Mile Races

One of the most useful things about this framework is how little it cares about where you are starting. The same principle that guides an ultrarunner through a hundred mile race guides a person who sits at a desk from nine to five. The aging process is real. The stress is real. But the maintenance is available to anyone willing to measure, and it is closer to an oil change than an overhaul.

How to Get Started

• Get measured. A MetFlex score turns guesswork into a plan, and you cannot manage what you have never seen
• Train in your personalized zone two, near the top of it, instead of chasing maximum output every session
• Treat fuel and engine as two separate projects: quality food pays off in proportion to your capacity to use it
• Stop assuming fatigue months in recovery is your baseline. There is a high degree of reversibility when you give the system the right stimulus
• Listen to the full episode on the HatchPath podcast, and watch the OVAL video series in the Member Hub Resource Library