8 Muay Thai Training Mistakes I’d Fix If I Started Again

I know you’re making Muay Thai training mistakes. Some of them are costing you right now. The rest will wait decades and then send you the bill.

You’re gassing out in the third round, so you run harder. Your kicks aren’t landing with power, so you kick more. It feels like the right answer because it’s what everyone tells you to do.

But you’re getting worse, and you can’t figure out why. I know because I made every one of these Muay Thai training mistakes myself.

Over nearly a decade of fighting and three decades coaching, I’ve broken my big toe on one foot, dislocated the big toe on the other, fractured ribs, separated a shoulder, and eventually needed hip resurfacing surgery from a career’s worth of needless wear and tear. I started competing at 32 with no coach and no corner, taught myself as I went, and by 40 I was UK ranked number four, beating fighters half my age. I’ve won fights and spent the night in hospital, lying there with electrodes on my chest, wondering how something so ordinary nearly ended me.

I’ve compressed everything I learned the hard way into the video below. If your training isn’t moving you forward, if you’re spinning your wheels and collecting injuries instead of progress, these eight lessons will show you exactly what to change.

Watch: 8 Lessons I’d Give My Younger Fighting Self

Don Heatrick · Muay Thai Performance Coachby Don Heatrick
@donheatrick

Like this episode?

Follow or subscribe at…

The Muay Thai Training Mistakes That Start With a Bad Diagnosis

Of all the Muay Thai training mistakes fighters make, treating the symptom instead of the problem is the one I see repeated most. You gas out in round three, so you run more. Your kicks lack power, so you kick harder. Your clinch fatigues quickly, so you clinch more. It’s logical on the surface, and it’s almost always wrong.

If you’re gassing out because your aerobic capacity isn’t generating enough energy, running harder won’t help. If your kicks lack power because your hip mobility is restricted, kicking more just reinforces the range you currently have. If your clinch fatigues quickly because your maximal pulling strength is low, more clinching won’t fix it. You cannot endure qualities you don’t have.

I use an IPO model from my engineering background to diagnose these problems. Input is the raw quality you develop. Process is how efficiently you transfer it, your technical skill. Output is what reaches the target, what your opponent feels. Most fighters keep adding to the process stage when the constraint is in the input, refining a delivery system that has nothing to deliver. Thais aren’t powerful, they’re efficient. They dominate the process stage (roughly 98% transfer efficiency), which means their biggest untapped gains are sitting in the input too. Diagnose which stage your constraint lives in before you reach for the fix.

The Muay Thai Overtraining Mistake That Cost Me a Hip Joint

My default was always do more. I was fit enough to recover, I was improving, so why doubt what was working?

I’ll tell you why. I’m in my fifties now, and I’ve already had hip resurfacing surgery in my left hip because of osteoarthritis from a high volume of kicking and running. My right hip is on borrowed time. I did way more than I needed to get the same results, and every unnecessary rep, every extra round, every session I did just because I could was compounding needless wear and tear. A cost you don’t feel until decades later.

The minimum effective dose isn’t just about training efficiency in the present. It’s about preserving your body for the long haul. Being fit enough to recover from excess volume is not the same as needing that volume to progress. If you can’t justify why a specific exercise or session is in your program, cut it. Targeted effort beats grinding effort, every single time. The body keeps a tally. It always does.

Training Through Pain: Why It’s One of the Costliest Muay Thai Training Mistakes

Training through pain is one of those Muay Thai training mistakes with compound interest. I’ve broken my big toe on one foot, dislocated the big toe on the other foot, broken ribs, fractured my elbow, separated my shoulder, and developed patella tendonitis and achilles tendonitis. All because I wouldn’t stop. I was a fighter who’d just run it off.

That attitude is great during a fight. In training, it’s a bloody liability, and the older you get, the more of a liability it becomes. A small amount of backing off at the right time can save you months of wasted time and missed opportunities. Backing off doesn’t mean stopping altogether. It means working around an injury, moving forward in other areas that don’t aggravate and slow up your rate of healing. Listen to your body. Short-term gain can end up a long-term loss, and long-term gain is where it’s at.

This applies to your brain health too. Research shows the accumulation of regular subconcussive blows is the real danger, not just the occasional heavy knockout shot. Technical sparring in Thailand proved to me that heavy headshots aren’t necessary in training. Save them for when you compete. Don’t make them part of your regular routine.

Confusing Fatigue With Progress: A Classic Among Muay Thai Training Mistakes

Confusing fatigue with adaptation is easily one of the most common Muay Thai training mistakes, and it took me years to spot it. For years I confused effort with progress. If a session left me knackered, I assumed it was working. I didn’t stop to ask whether the fatigue was actually producing adaptation, or just accumulating fatigue I’d eventually pay for.

Feeling destroyed is not the same as adapting. They’re different biological processes, and they don’t always overlap. You can run yourself into the ground for months and come out the other side no faster, no stronger, no fitter. Just more tired and more injured. I’ve done it. I’ve got the surgical scars to prove it.

The question I wish I’d asked earlier: is your training actually making you better or just making you feel tired? If you can’t answer that with something specific, a measurable improvement in a quality that matters to your performance, then you’re just grinding for the sake of it.

Muay Thai for Older Fighters: The Late Starter’s Advantage

I didn’t start fighting until I was 32. No coach, no corner, no ringcraft. I trained on mats. In my first year I won three area titles at three different weights, was selected for England at 34, fought at the world championships, and won a silver European medal. At 35 the amateur rules deemed me too old, so I turned pro. By 40 I was UK ranked number four, beating fighters half my age.

I didn’t retire because of age. I retired because of an elbow surgery that had nothing to do with being old, and everything to do with smashing my elbow down on top of opponents’ heads in the ring. Honestly, careful with that one.

My secret as a veteran fighter was my physicality. My S&C was so far ahead I could drown younger fighters in work rate. I was just a tough, relentless bugger. Late starters have advantages most people overlook. You’re more strategic about how you learn, you’re more efficient with your training time, and you’ve got the psychological maturity to handle setbacks. Believing you’ve missed your window is one of the most damaging Muay Thai training mistakes you can make. Most people give up on themselves without truly reaching their limits. Refusing to believe the story you tell yourself about your limits is what determines how far you go, not how early you start. The best time to plant a tree was 20 years ago. The second best time is now.

Push to the Limit on Purpose, Not by Default

Every session should push you to your limit at some point. I always program a finisher at the end, something that tests grit and reinforces the fighter’s identity. You need to know you can go there when it counts. In a typical four-week training block, the high week is where most sessions push the limit. The other weeks vary the intensity.

Pushing on purpose isn’t the same as pushing by default. My default was to push every time, it’s one of the hardest Muay Thai training mistakes to acknowledge, and it cost me. The session finisher is intentional, and prescribed. You choose it, you smash it, you recover from it. You don’t let it become the whole session, the whole week, the whole career. Most Muay Thai training mistakes start right there.

I won what turned out to be my last fight, but I was taken by ambulance to hospital immediately afterwards to spend the night under observation. Six hours after the fight, my resting heart rate was still 83 beats per minute. Normally it’s 45. My blood lactate was still 14 mmol/L. My body wasn’t recovering. It was under severe physiological stress. But I finished that fight, and I won it, because I’d conditioned myself physically and mentally to meet the challenge head-on. The same relentlessness that gets you through a finisher is the relentlessness that gets you through a fight where your body is failing you. It’s a weapon and a liability. The skill is knowing which one it is right now. Use it deliberately. Always respect it.

muay thai performance scorecard

Connect The Dots: Your Muay Thai Performance

Knowledge is powerful—but only when it fits into a complete system.

The 5-minute Performance Scorecard shows:

✓ How this piece fits your overall training puzzle
✓ Which areas need immediate attention
✓ Your personalized next steps for improvement

Take the free assessment to see exactly where you stand.

Further Resources

What to Watch Next

If you’re wondering how to actually apply that IPO model and figure out whether your constraint is in the input or the process, I’ve got a video that walks through exactly how to diagnose where your biggest gains are hiding.

Muay Thai Performance Series

Here’s our comprehensive series on Muay Thai performance training:

Building Advanced Foundations

I’ve made a lot of mistakes in my fighting career. Some of them cost me titles, some of them cost me years, and one of them cost me a hip joint.

I didn’t start competing as a fighter until I was 32, and I still made it work. So if you’re older and wondering whether any of this applies to you, it does. Especially Lesson 6. This is the advice I wish someone had given my teenage self.

 Lesson 1: Don’t wait for someone to give you permission

At one of my early fights, my corner team, my mates from the gym, dropped my gumshield in a spit bucket of bleach between rounds. After a quick rinse I put it back in and it burned. The referee had to call timeout. “What the hell’s going on here?” Luckily, I still got the win.

That’s where I started. No coach, no real corner, just figuring it out as I went. When I started out, Muay Thai coaches were extremely rare in Suffolk. I was stuck in a gym with no fighters. My coach actually told me, “Fighters are bad news for the gym. If you want to do it, you’ll have to sort out your own training, arrange your own fights and corner men.” So that’s what I did.

In my first year on the English amateur scene I’d won four titles at three different weight classes and been picked to represent England at the World Championships in Bangkok. I’d spent years waiting for someone to tell me I was ready. Don’t do that. If there’s a fire in you, find a way and chase it. Find out for yourself how far you can go. Don’t let someone else decide that for you.

Now, before I go any further. If you’re watching this and wondering whether your own training is actually moving you forward or just keeping you busy, I’ve put together a free Muay Thai Performance Readiness Scorecard. It’s sixteen questions, takes less than five minutes, and you get a personal score and custom resources telling you exactly where to focus and what to skip. No generic advice. Just a clear snapshot of where you stand right now. Link in the description and more on that at the end.

Lesson 2: Diagnose the constraint before you prescribe the fix

The biggest trap I see fighters fall into is treating the symptom instead of the problem. You’re gassing out in the third round, so you run harder. Your kicks aren’t landing with power, so you try kicking harder. Your clinch is weak, so you clinch more.

If you’re gassing out because your aerobic capacity isn’t generating enough energy, running harder won’t help. If your kicks lack power because your mobility is restricted, kicking more just reinforces the range you currently have. If your clinch fatigues quickly because your maximal pulling strength is low, more clinching won’t fix it. You can’t endure qualities you don’t have.

I use an IPO, Input-Process-Output model from my engineering background. Input is the raw quality you develop. Process is how efficiently you transfer it, your technical skill. Output is what reaches the target, what your opponent feels. Most fighters keep adding to the process stage when the constraint is in the input. Thais have the opposite problem. They aren’t powerful, they’re efficient. They dominate the process stage, which means their biggest untapped gains are sitting in the input. Diagnose which stage your constraint lives in before you reach for the fix.

Lesson 3: Do less than you think you need to

My default was always “do more.” Just because you can doesn’t mean you should. I was fit enough to recover, I was improving, so why doubt what was working?

I’ll tell you why. I’m in my fifties now, and I’ve already had hip resurfacing surgery in my left hip because of osteoarthritis from a high volume of kicking and running. My right hip’s also on borrowed time. I did way more than I needed to get the same results. Every unnecessary rep, every extra round, every session I did just because I could was compounding needless wear and tear. A cost you don’t feel until decades later.

The minimum effective dose isn’t just about training efficiency in the present. It’s about preserving your body for the long haul. Being fit enough to recover from excess volume is not the same as needing that volume to progress. If you can’t justify why a specific exercise or session is in your program, cut it. Targeted effort beats grinding effort, every single time.

The body keeps a tally. It always does.

Lesson 4: Stop when it hurts. Training is not a fight.

I’ve broken my big toe on one foot, dislocated the big toe on the other foot, broken ribs, fractured my elbow, separated my shoulder, developed patella tendonitis and achilles tendonitis. All because I wouldn’t stop. I was a fighter who’d just “run it off.”

That “do or die” attitude is great during a fight. In training, it’s a bloody liability. And the older you get, the more of a liability it becomes.

A small amount of backing off at the right time can save you months of wasted time and missed opportunities. And backing off doesn’t mean stopping altogether. It means working around an injury, moving forward in other areas that don’t aggravate and slow up your rate of healing. Listen to your body. Short-term gain can end up a long-term loss, and long-term gain is where it’s at.

And this isn’t just about joints and tendons. As a kid I played rough. Falling out of trees, off skateboards, crashing bikes, rolling down hills inside a metal drum. Most weeks I’d have a bell ringer. I ended up in hospital twice for concussion, seeing double and being sick. This, for me, was normal. My early days in martial arts in the 90s continued to shell out blows to the head in heavy sparring too. But technical sparring in Thailand proved it isn’t necessary. Research shows the accumulation of regular subconcussive blows is the real danger to your brain health, not just the occasional heavy knockout shot. Save heavy head shots for when you compete. Don’t make it part of your regular training. I think I’ve gotten away with it… haha, you tell me.

Lesson 5: Push to the limit on purpose, not by default

Now, after those last two lessons, you might think I’m saying never push yourself. I’m not. Every session, at some point, you should push yourself to your limit. I always program a finisher at the end of a session. Something that tests grit and reinforces the fighter’s identity. You need to know you can go there when it counts. In a typical four-week training block, the high week is where most sessions push the limit too. The other weeks vary the intensity. Training must always be at least at the minimum developmental dose to trigger improvement, but you don’t always go all out. That’s not training. That’s just collecting fatigue and micro-damage you don’t need to carry.

Pushing on purpose isn’t the same as pushing by default. My default was to push every time. It cost me. The session finisher is intentional. You choose it, you smash it, you recover from it. You don’t let it become the whole session, the whole week, the whole career.

I won what turned out to be my last fight, but I was taken by ambulance to hospital immediately afterwards to spend the night under observation. Of all my fights, that one felt the most physically gruelling. It was like my opponent was wearing kryptonite, because my trademark physical fitness had disappeared. I’d dropped him with a knee to the face in round one, but then things started to feel wrong. I was tired, really tired. I couldn’t shift gears, my power had gone. It turned out I’d had a rare reaction to a nasal decongestant spray. Tachycardia. It affects less than 0.01% of the population. My heart was pumping faster but not pumping properly.

By the time I got to hospital, six hours after the fight, my resting heart rate was still 83 beats per minute. Normally it was 45. My blood lactate was still 14 mmol/L. My body wasn’t recovering properly. It was under severe physiological stress.

But I finished the fight, and I won it. I nearly collapsed climbing out of the ring, but I won. And the reason I didn’t quit when my body was packing up is the same reason I’d programmed finishers for years. I’d conditioned myself, physically and mentally, to meet the challenge head-on or die trying. I didn’t intend to take that quite so literally, but the habit was already there. It was built in every finisher, every high week, every moment I’d chosen to push on purpose.

The same relentlessness that gets you through a finisher is the relentlessness that gets you through a fight where your body is failing you. It’s a weapon and a liability. The skill is knowing which one it is right now. Use it deliberately. Always respect it.

That sleepless night in the Addenbrooks hospital, lying there with electrodes on my chest, a continuously beeping heart rate monitor, and an IV in my hand. I thought about something that bothered me more than the numbers on the monitor. I’d felt well enough to step into the ring. I’d assumed that because it was only a nasal spray, it couldn’t have much effect. I was wrong. Even over-the-counter medications can have significant effects when combined with maximal exertion. I’d always assumed the danger would come with a warning. It didn’t.

Lesson 6: It’s never too late. Your late start is an advantage.

I didn’t start fighting until I was 32. No coach, no corner, no ringcraft. I trained on mats. In my first year I won three area titles at three different weights. I was selected for England at 34, fought at the world championships, and won a silver European medal. At 35 the amateur rules deemed me too old, so I turned pro. By 40 I was UK ranked number four, beating fighters half my age.

I didn’t retire because of age. I retired because of an elbow surgery that had nothing to do with being old, and everything to do with smashing my elbow down on top of opponents’ heads in the ring. Honestly, careful with that one.

My secret as a veteran fighter was my physicality. My S&C was so far ahead I could drown younger fighters in work rate. I was just a tough, relentless bugger.

Late starters have advantages most people overlook. You’re more strategic about how you learn, you’re more efficient with your training time, and you’ve got the psychological maturity to handle setbacks. Most people give up on themselves without truly reaching their limits. Refusing to believe the story you tell yourself about your limits is what determines how far you go, not how early you start. The best time to plant a tree was 20 years ago. The second best time is now.

Lesson 7: Ask yourself: is this making me better or just making me tired?

For years I confused effort with progress. If a session left me knackered, I assumed it was working. I didn’t stop to ask whether the tiredness was actually producing adaptation, or just accumulating fatigue I’d eventually pay for.

Feeling destroyed is not the same as adapting. They’re different biological processes, and they don’t always overlap. You can run yourself into the ground for months and come out the other side no faster, no stronger, no fitter. Just more tired and more injured. I’ve done it. I’ve got the surgical scars to prove it.

The question I wish I’d asked earlier: is your training actually making you better or just making you feel tired? If you can’t answer that with something specific, a measurable improvement in a quality that matters to your performance, then you’re just grinding for the sake of it.

Lesson 8: Find the activity that fits you. Everything else follows.

I played football as a kid at school before I found Muay Thai. But I was too physical for it. As an adult, my engineering company’s five-a-side tournament got cancelled after I played for the R&D team. In response to my style, fights broke out and shirts got ripped. The sport wasn’t for me.

Rugby and American football were better fits. Next was martial arts and combat sports. Although I’d get disqualified from semi-contact kickboxing before I found Muay Thai. And it gave me the freedom to express myself within the rules. I could play fair and still perform in a way that was truly me. I didn’t inadvertently break rules or upset people. I just had to find the right vehicle. And for me, that’s Muay Thai.

This is true within Muay Thai too. Padwork may be enough for you right now. Sparring may be enough. Amateur competition may be enough. Or pro rules might be what you need. Not everyone needs to aim at pro level. Big goals are good, but the realistic next-level challenge is what’s important. Reflect and recognise when the current challenge isn’t enough, then find the activity that sets the right challenge for you right now. That’s when the magic happens.

Muay Thai is the vehicle. Self-actualization is the destination, not the fight. The training is. The fight is just one kind of test.

Now, if any of these lessons hit home, especially Lessons 2 through 7, and you’re wondering where your own training stands right now, I mentioned the scorecard earlier. It’s free. Sixteen questions you can answer in five minutes. You get a personal score and custom resources that show you exactly where to focus and what to skip. If you’re stuck, if you’re spinning your wheels, if you’re not sure whether your S&C is actually helping your Muay Thai or just making you sore, this will give you a clear answer. Link in the description. Take it. It costs you five minutes and it might save you years.

And if you’re wondering how to actually apply that IPO model from Lesson 2, how to figure out whether your constraint is in the input or the process, I’ve got a video that walks through exactly how to diagnose where your biggest gains are hiding. I’ll put it on screen now. Click it. I’ll see you there.

Don Heatrick · Muay Thai Performance Coach

Don Heatrick

Founder of Heatrick Muay Thai Performance

Don Heatrick is a Level 4 Strength & Conditioning Coach and former pro Muay Thai fighter who helps practitioners turn limited training time into real Muay Thai performance gains.

With 25 years of Muay Thai coaching experience and an engineering background, he creates systematic, science-backed Muay Thai performance programs that cut through the confusion and deliver real progress without burnout. Learn more about Don’s approach →

Follow Don Heatrick on YouTube:

Go to Top