Deep, bone-crushing fatigue doesn’t respond to coffee or extra sleep.
That’s because the problem isn’t a lack of energy—it’s that cells can’t use the energy being provided.
According to health and wellness expert Thomas DeLauer, in a recent video breaking down cellular fatigue, a simple half cup of bone broth may do more for exhaustion than a third or fourth cup of coffee.
The reason? Bone broth contains glycine, magnesium, and amino acid precursors that mitochondria need to produce ATP and support antioxidant systems like glutathione—addressing fatigue at its source rather than masking it.
Jump to:
Why Cells Stop Producing Energy Efficiently
Most people assume fatigue means they’re not getting enough calories or fuel.
But energy production and energy availability are two entirely different things. Someone can eat plenty of food and still feel exhausted—commonly seen in insulin resistance, where calories can’t enter cells properly.
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DeLauer explains that calories need to be accessed, processed, and converted into ATP through an electrochemical process inside mitochondria. Think of it like a car with a full gas tank but a misfiring engine.
The fuel is there. That’s not the problem. The problem is that can’t burn the fuel efficiently. Your mitochondria are that engine.
Mitochondria take substrates—carbohydrates, fats, amino acids—and run them through oxidative metabolism to produce energy. If any part of that process is impaired, energy production stalls even when fuel is abundant.
Fatigue Shows Up During Transitions
DeLauer notes that this energy dysfunction becomes most noticeable during transitions: rest to activity, low stress to high stress, or short efforts to longer duration tasks.
These transitions demand quick changes in mitochondrial output. When mitochondria can’t ramp up fast enough, the nervous system compensates by jacking up sympathetic drive—cortisol and fight-or-flight responses—to squeeze out energy through stress pathways instead of normal metabolic ones.
That creates the “wired but tired” feeling—amped up on the outside, exhausted at the core.
Over time, relying on stress-driven energy makes everything worse. If standing up from a chair or transitioning from a walk to a run triggers immediate fatigue, that’s a sign of mitochondrial signaling problems, not fuel availability issues.
If you want something simple that actually works, this is one of the most effective tools I’ve used to build strength, conditioning, and endurance without needing a full gym setup.
- Full-body training with one weight using swings, squats, and presses
- Solid cast iron build that feels stable and lasts for years
- Comfortable grip that makes high-rep workouts easier to handle
Understanding Spare Respiratory Capacity
DeLauer introduces a critical concept called spare respiratory capacity (SRC)—essentially the mitochondrial buffer zone.
SRC represents the difference between how much energy mitochondria produce at rest and how much they could produce if demand suddenly spiked. It’s the reserve tank.
A mechanistic review in the FASEB Journal synthesized data from cellular respiration studies and defined SRC as the maximum respiratory capacity beyond basal ATP demand. Cells with high SRC tolerate increased workload and oxidative stress well. Cells with low SRC reach maximum respiration quickly and accumulate significantly more oxidative stress and reactive oxygen species (ROS).
When your buffer zone is depleted, you have two bad things happening. You can’t produce ATP for one and the attempt to produce more is generating oxidative stress that damages your cells.
Fatigue from low SRC feels qualitatively different from sleepiness. It’s deep, bone-level exhaustion—the kind where the body feels like it’s fighting itself, because in a very real sense, it is.
Two Ways to Protect Spare Respiratory Capacity
First, stop living at maximal output. Constant high demand—mental, physical, emotional stress—prevents SRC from recovering. This is measurable through heart rate variability (HRV), which reflects mitochondrial buffer capacity.
Mitochondria respond best to intermittent, recoverable stress, not chronic overload.
If you want something simple that actually works, this is one of the most effective tools I’ve used to build strength, conditioning, and endurance without needing a full gym setup.
- Full-body training with one weight using swings, squats, and presses
- Solid cast iron build that feels stable and lasts for years
- Comfortable grip that makes high-rep workouts easier to handle
Second, avoid frequent blood sugar crashes. Hypoglycemia forces emergency ATP production through stress signaling, which burns through SRC rapidly. Steady fuel and stable blood glucose—not spikes and crashes—preserve mitochondrial capacity.
The Reactive Oxygen Species Feedback Loop
ROS doesn’t just accumulate passively—it creates a vicious feedback loop.
Under normal conditions, mitochondria produce ROS as a byproduct of the electron transport chain. But when the chain runs inefficiently—especially when SRC is low and mitochondria are pushed beyond capacity—ROS production skyrockets.
This causes three specific problems:
- Electron transport chain efficiency drops further
- Oxidative damage occurs to lipids, proteins, and DNA—the structural components of mitochondria
- Inflammatory signaling pathways activate, further impairing mitochondria and producing even more ROS
It’s self-reinforcing and likely the main mechanism linking mitochondrial dysfunction to chronic fatigue.
Diet as the Biggest Lever Against Inflammation
A meta-analysis in Nutrition Reviews examined 33 randomized controlled trials with 3,500 people. Researchers found that a Mediterranean-style diet reduced high-sensitivity CRP, IL-6, and IL-7 compared to control diets.
If you want something simple that actually works, this is one of the most effective tools I’ve used to build strength, conditioning, and endurance without needing a full gym setup.
- Full-body training with one weight using swings, squats, and presses
- Solid cast iron build that feels stable and lasts for years
- Comfortable grip that makes high-rep workouts easier to handle
DeLauer clarifies that the benefit isn’t about carbs or reducing saturated fat—it’s about polyphenols, antioxidants, omega-3s, fiber, and adequate protein. These compounds support glutathione and superoxide dismutase, neutralizing ROS and protecting mitochondria.
I’m not saying you need to eat a Mediterranean diet. I’m saying you need to apply Mediterranean principles to a lot of the other things that I teach.
His recommendations:
- Eat low-carb, low-glycemic
- Prioritize protein, especially first thing in the morning
- Minimize ultra-processed foods
- Include olive oil, avocados, salmon, lentils, and Mediterranean spices
- Ditch most grains
On the lifestyle side, DeLauer suggests grounding—10 minutes barefoot on grass allows electron transfer that preliminary research suggests reduces systemic inflammation. Brief cold exposure activates cold shock proteins and reduces inflammation. And that half cup of bone broth? The glycine is a direct precursor to glutathione, the main antioxidant needed to break the ROS cycle.
The Micronutrient Gaps Starving Your Electron Transport Chain
Mitochondria are complex machinery, and critical parts—cofactors, structural components, redox carriers—come from vitamins and minerals.
Even suboptimal levels impair mitochondrial capacity enough to cause fatigue. A review in Biomedicine & Pharmacotherapy found that many micronutrients are essential cofactors in complexes 1 through 4 of the electron transport chain, antioxidant systems, and redox carriers like coenzyme Q10.
Deficiency at any point stops or impairs ATP production, causes electron leakage, and allows oxidative stress to accumulate.
If you want something simple that actually works, this is one of the most effective tools I’ve used to build strength, conditioning, and endurance without needing a full gym setup.
- Full-body training with one weight using swings, squats, and presses
- Solid cast iron build that feels stable and lasts for years
- Comfortable grip that makes high-rep workouts easier to handle
The Big Four Micronutrients for Mitochondrial Function
B vitamins (B1, B2, B3, B5): Cofactors for the TCA cycle and NAD generation. Without them, fuel cannot be processed. Found in eggs, meat, fish, wheat germ, and lentils.
Magnesium: Supports electron transport complexes directly and is involved in 300+ enzymatic reactions. Sources include dark chocolate, dark leafy greens, and supplements like dimagnesium malate, magnesium glycinate, or magnesium taurate.
Iron from real food: Critical for electron transport chain complexes. DeLauer warns against iron supplements, which can cause oxidation issues. Get heme iron from organ meats, red meat, or pumpkin seeds for plant-based sources.
Coenzyme Q10: Essential for electron transport between complexes. Best sources are organ meats, fatty fish (mackerel, sardines, salmon), pistachios, sesame seeds, and toasted sesame seed oil.
If fatigue is your main complaint and you haven’t really addressed those four things, start there. A good B complex and CoQ10 can really move the needle more than another cup of coffee.
How Stress Rewires Mitochondria
Stress and mitochondria have a bidirectional relationship.
A study in Frontiers in Neuroendocrinology laid out four key connections between stress and mitochondrial function:
If you want something simple that actually works, this is one of the most effective tools I’ve used to build strength, conditioning, and endurance without needing a full gym setup.
- Full-body training with one weight using swings, squats, and presses
- Solid cast iron build that feels stable and lasts for years
- Comfortable grip that makes high-rep workouts easier to handle
- Stress responses require ATP from mitochondria—every stress event is an energy draw
- Mitochondria are involved in producing and metabolizing stress hormones
- Neuroendocrine signals like cortisol influence mitochondrial function
- When mitochondrial energetics are experimentally manipulated, organisms’ physiological and behavioral responses to stress change
In other words, mitochondrial health determines how stress is experienced.
Chronic cortisol exposure drives up ROS, impairs ATP, and alters metabolic signaling within mitochondria. Combined with SRC depletion, chronic stress creates constant, lingering fatigue.
For training stress, prioritize nutrient-dense food, micronutrients, and quality sleep above actual training. For psychological stress, practice nasal breathing, walk outside, spend time in nature, and consider vagal nerve stimulators.
DeLauer also credits ketamine-assisted therapy as a tool that helped him address underlying stress patterns formed early in life.
The Morning Habit That Was Sabotaging Energy
Mitochondria don’t operate at the same capacity 24/7—they fall under circadian control.
When energy is demanded matters just as much as how much. A study in the Journal of Molecular Endocrinology confirmed that mitochondrial respiration is rhythmic. Oxygen consumption, ATP efficiency, and ROS generation undergo predictable oscillations throughout the day.
If you want something simple that actually works, this is one of the most effective tools I’ve used to build strength, conditioning, and endurance without needing a full gym setup.
- Full-body training with one weight using swings, squats, and presses
- Solid cast iron build that feels stable and lasts for years
- Comfortable grip that makes high-rep workouts easier to handle
When timing is aligned, mitochondria can anticipate demand. When misaligned, they’re constantly reacting under stress—like a factory asked to produce at peak capacity during the night shift with a skeleton crew.
A study in Cell Metabolism put people with pre-diabetes on either early time-restricted feeding (6-hour eating window before 3 p.m.) or a 12-hour control for five weeks, then crossed over. The early feeding group showed significantly improved insulin sensitivity, beta cell responsiveness, blood pressure, oxidative stress, and appetite—all without weight loss.
Just by aligning food earlier, participants improved mitochondrial substrate handling, reduced oxidative stress, and improved metabolic efficiency. No calorie changes, no supplements—only timing.
Why Skipping Breakfast Every Day Backfired
For years, DeLauer skipped breakfast and fasted 16 to 18 hours daily, thinking it helped him stay lean.
But skipping breakfast every morning keeps cortisol elevated to maintain blood sugar. The body uses stress hormones as a substitute for food-derived fuel. DeLauer was running his mornings on stress hormones and calling it discipline—while his mitochondria paid the price.
I was running my mornings on stress hormones and calling it discipline. And my mitochondria was paying the price.
His solution: eat breakfast three to four days per week, with a high-protein meal (70 to 100 grams of protein) within a couple hours of waking. Eggs, meat, avocados, and healthy fats signal to the body that resources are available, allowing cortisol to drop.
If you want something simple that actually works, this is one of the most effective tools I’ve used to build strength, conditioning, and endurance without needing a full gym setup.
- Full-body training with one weight using swings, squats, and presses
- Solid cast iron build that feels stable and lasts for years
- Comfortable grip that makes high-rep workouts easier to handle
On the other three to four days, he does longer fasts (18 to 20 hours) to get deep fasting benefits: bottomed-out insulin, cellular resensitization, and autophagy. Total net fasting hours over the week remain the same, but morning mitochondrial function is preserved most days.
Practical Steps to Fix Cellular Fatigue
Work with biology instead of against it:
- Frontload calories earlier in the day
- Keep a consistent sleep-wake schedule so mitochondria can anticipate demand
- Avoid late-night training
- Get morning sunlight within the first hour of waking
- Don’t fast every single day
- Get B vitamins, magnesium, iron from real food, and coenzyme Q10
- Sip bone broth before coffee
DeLauer emphasizes that addressing cellular fatigue isn’t about pushing harder—it’s about giving mitochondria the right fuel, timing, and recovery they need to function efficiently.
