Your Muscles Are Lying to You

Let me ask you something. When was the last time you actually thought about why you train the way you do, not just what your coach told you, not just what you've always done, but the actual science behind why any of it works?

Because here's the truth: most fighters are leaving huge gains on the floor. Not because they're not working hard. You're working hard. But because nobody's ever broken down the neuroscience of how your body actually builds strength, builds muscle, and recovers so you can come back stronger the next session.

I was deep in a Huberman Lab Essentials episode recently, the one on muscle size, strength, and recovery, and it confirmed a lot of what I've been coaching for years, while also throwing a few things at me that made me rethink parts of how I structure fighter S&C. I'm going to break it all down here. Fighter first, without any fluff.

1. Your Brain Controls Your Muscle - Not the Other Way Around

This is the most underappreciated thing in fighter training. Muscle doesn't move itself. Your nervous system drives everything. Upper motor neurons sit up in your motor cortex and fire signals down to lower motor neurons in your spinal cord. Those lower motor neurons release acetylcholine onto your muscle fibres, and that is the only way muscle contracts.

What does this mean for you as a fighter? It means that getting stronger, more explosive, and more powerful is fundamentally a neuromuscular problem. Your ability to recruit muscle fibres on demand, under pressure, under fatigue, in round 3 when everything is telling you to slow down, that is a trainable neurological skill.

The biggest thing that gets lost: jumping ability and the ability to generate force quickly are some of the most predictive markers of both athletic performance and healthy ageing. If you can't load and explode, you can't fight, and eventually, you can't function. That's why this matters beyond the gym.

2. Henneman's Size Principle - The Rule That Changes How You Train

Here's the principle most fighters have never heard of, but it should be shaping every session you do.

Henneman's Size Principle says that your body recruits motor units, the nerve-to-muscle connections, from low threshold to high threshold. When you pick up something light, you use the minimum motor units needed to move it. When you go heavy or go to near failure, your body is forced to recruit high-threshold motor units, the ones that drive real strength and real growth.

Here's the part that surprises a lot of people: you don't need to always go maximally heavy to recruit those high-threshold motor units. The research from exercise physiologists like Andy Galpin and Brad Schoenfeld shows that working in the 30-80% of your one-rep maximum range, and pushing close to failure, is what opens the door to strength and hypertrophy gains. Not just grinding through your max every session.

For fighters, this is huge. You don't always need to be maxing out to get stronger. What you need is sufficient stimulus + smart volume + near-failure effort. That's the combination that changes you.

3. Strength vs. Size - Know Which One You're Training

This is where most fighters get confused, and it matters because your training goal changes everything about how you structure your S&C.

Training for strength means distributing effort across muscle groups. Compound movements. The whole nervous system works together to move load.

Training for hypertrophy means isolating specific nerve-to-muscle pathways. Challenge the muscle, don't just move the weight. That mind-muscle connection isn't bro science, it's neuroscience.

A test I want you to try right now: mentally march through your body and try to deliberately contract each muscle group in isolation. Can you cramp your lat without pulling anything? Can you fire your calf hard enough to feel it about to cramp? If you can, that muscle has strong upper-motor-neuron control, and it will respond well to hypertrophy training. If you can't isolate it, you'll need more volume to get results there.

The better your neural control, the fewer sets you need to stimulate change. The worse your control, the more volume required. Know your body.

4. The Volume Protocol - How Many Sets Actually Work

Let's cut through the noise. Here's what the research actually says:

• 5 sets/week per muscle group = maintenance. That's the floor. Drop below this and you're losing ground.
• 10-15 sets/week per muscle group = where growth and strength gains happen for most people.
• Up to 25-30 sets/week = territory for experienced, well-recovered athletes, but only if you can handle it.
• 30-80% of your 1RM = the working range. Lower end biases hypertrophy; higher end biases strength.
• 90% of sets = should end near failure, not at failure. Save full failure for about 10% of your work.
• 45-60 minutes = optimal session length. Beyond 60-75 minutes, cortisol rises and recovery tanks.

For fighters with stacked training weeks, technique, sparring, conditioning, this matters. You don't have to do all your sets in one session. Spread across 2 sessions per week. What matters is hitting the weekly volume target.

5. Building Explosiveness - The Speed-Force Equation

This one is specifically for you, fighter. If your goal is to hit harder, move faster, generate more knockout power, listen up.

Learning to move moderate-to-heavy loads as fast as you safely can trains the upper motor neurons to fire in ways that translate directly to speed and power. The adaptations happen primarily in the nervous system, not just the muscle. This is why two fighters can have similar muscle mass and completely different levels of knockout power.

The key: don't train to failure when you're working on explosiveness. As soon as the bar slows down significantly from fatigue, the neural stimulus for speed is gone. Keep the quality high. Stop the set before the speed drops out.

Working zone: 60-75% of 1RM, executed with maximum intent on every rep. This is how you build a punch that actually lands differently.

6. The Testosterone Protocol - 6x10 Is the Number

Duncan French, VP of the UFC Performance Institute, found in research from his time at University of Connecticut that the optimal protocol for stimulating testosterone release is:

6 sets x 10 reps | compound movements | 2-minute rest between sets

What's remarkable: 10 sets of 10 actually reversed the effect. Testosterone didn't increase, cortisol went up instead. Four extra sets completely flipped the hormonal outcome. That's the precision required.

For fighters who want to use their S&C sessions to optimise hormonal output, not just physical output, this protocol done twice a week with big compound movements is your tool. Squats, deadlifts, pull-ups, bench, compound, hard, precise.

7. Recovery - This Is Where You Actually Get Better

Nothing in your training actually improves during training. It improves during recovery. Your neurons rewire, your muscle fibres rebuild, your hormones rebalance, all of that happens after. If you're not recovering, you're not progressing. You're just accumulating damage.

How to test if you've actually recovered:

• HRV (Heart Rate Variability) - Track it with a device. High HRV = recovered nervous system. Low or dropping HRV = don't push intensity today.
• Grip Strength - First thing in the morning, squeeze something and gauge relative to your baseline. A 10-20% drop signals that your neuromuscular system hasn't bounced back yet. Free, fast, surprisingly accurate.
• CO2 Tolerance Test - My favourite. Do 4 breath cycles, in through nose, out through mouth, then take a fifth maximal inhale and exhale as slowly as possible. Time how long you can sustain it.

Do this every morning for 2 weeks. You'll start seeing your own patterns: how sparring affects you differently to a heavy lift session, how sleep quality shows up in your CO2 time, how overtraining reveals itself long before you feel it in the gym.

8. Cold, NSAIDs, and What's Costing You Your Gains

Two things fighters do habitually that may be sabotaging their strength and muscle development:

• Ice baths immediately after resistance training - Cold within 4 hours post-lift blunts the mTOR pathway and the inflammatory cascade that triggers muscle repair and growth. Yes, it reduces soreness, but it also reduces adaptation. If you're primarily training for strength and size, save the cold for the morning after, or use it before strength sessions, not after. Palmar cooling, cold on the hands only, is a different story. That actually enhances performance without the same downstream downside.
• NSAIDs and antihistamines - Ibuprofen and similar anti-inflammatories taken around training can block the exact inflammatory signals your body needs to adapt. Some data also suggests antihistamines interfere with cardiovascular and resistance adaptations. Use these tools carefully, not as default recovery habits.

9. Nutrition & Supplements - What Actually Moves the Gains

I'm not going to turn this into a full nutrition lecture, but here's what the research clearly supports.

The Non-Negotiables

Electrolytes (Salt/Sodium, Potassium, Magnesium)

Your neurons fire via electrical signals driven by ion movement, primarily sodium. Low electrolytes = poor nerve-to-muscle communication = weaker contractions, slower reaction times, impaired brain function. This is not optional. Hydration without electrolytes is not enough. Another reason myself and a ton of fighters I work with are using Wilder.

Leucine (700-3,000mg per meal)

The amino acid that triggers muscle protein synthesis. Found in high-protein animal foods, steak, chicken, fish, eggs. Per calorie, animal proteins deliver more essential amino acids than plant sources. If you're serious about building lean muscle for performance, your protein sources matter.

Omega-3 / EPA (1,000mg+ daily)

Foundational for keeping systemic inflammation low and allowing you to absorb training stress over time. Think of it as your baseline anti-inflammatory protocol.

Vitamin D3

Critical for immune function, hormone production, and muscle performance. Most fighters, especially those training indoors, are deficient.

Magnesium Malate

Specifically effective at reducing delayed onset muscle soreness (DOMS). Note: soreness is not required for growth, but if you're experiencing it, this helps manage it without blocking adaptation.

Performance Enhancers

Creatine (3-5g daily for ~80kg athletes, 10-15g for larger athletes)

Sixty-six studies. Power output up 12-20% across sprinting, jumping, lifting. Improves cell hydration. Has cognitive benefits. Supports short-duration, high-intensity explosive efforts, exactly what fights are made of. This is as close to mandatory as supplementation gets for fighters.

Beta-Alanine (2-5g daily)

Specifically supports efforts in the 60-240 second range, rounds, intervals, hard conditioning pieces. Improves muscular endurance and anaerobic capacity. Causes a harmless tingling sensation. Works best for the grappler grinding through position or the fighter who needs to maintain output into late rounds.

10. The 10% Rule - Train Your Brain and Your Body at the Same Time

About 10% of your training should push you into the burn, that zone where lactate floods the muscle and you're working through it. Not more than 10%. Not every session. Just a controlled portion.

Why? Because lactate isn't just a fuel buffer, it buffers against acidity, allowing you to keep working. It also acts as a hormonal signal that travels to your heart, liver, and brain and drives positive adaptations there. You're literally training your entire physiology, not just your muscles, when you push into that burn zone with intentional breathing to drive more lactate into the working tissue.

And when you hit that burn, breathe. Deep nasal inhales. Don't hold your breath. That oxygen availability is what lets the lactate do its job.

The Bottom Line

Fighting is a neuromuscular sport. The fighter who recruits muscle faster, more efficiently, and under more extreme conditions wins. That isn't just about how much you train, it's about how intelligently you train.

The science is clear: volume matters, specificity matters, recovery matters, and what you put in your body matters. None of these things are guesswork anymore. Apply what's here, track your CO2 tolerance, hit your sets, protect your recovery windows, and fuel like the performance machine you're trying to build.

Every adaptation you're chasing happens after the session is over. Train smart enough to actually get there.

Sources & Further Reading

• Huberman, A. (2025). Essentials: Build Muscle Size, Increase Strength & Improve Recovery. Huberman Lab Essentials.
• Huberman, A. (2021). Science of Muscle Growth, Increasing Strength & Muscular Recovery. Huberman Lab.
• Galpin, A. (Andy Galpin, PhD). Research on resistance training volume, motor unit recruitment, and recovery measurement. andygalpin.com
• Schoenfeld, B. (2010). The Mechanisms of Muscle Hypertrophy and Their Application to Resistance Training. Journal of Strength and Conditioning Research, 24(10), 2857-2872.
• French, D.N. et al. (2003). The effects of in-season strength training on endurance distance athletes. Journal of Strength and Conditioning Research. Referenced re: 6x10 testosterone protocol - Duncan French, VP UFC Performance Institute.
• Roberts, M.D. et al. Research on resistance training adaptations. Auburn University.
• Examine.com. Creatine Research Summary. 66+ studies on power output and performance.
• Henneman, E., Somjen, G., & Carpenter, D.O. (1965). Functional significance of cell size in spinal motoneurons. Journal of Neurophysiology, 28(3), 560-580. Henneman's Size Principle.