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From Lab to Locker Room – Performance Unchained Insider (Ed.9)

Welcome to Edition 9 of Performance Unchained Insider: From Lab to Locker Room!


In this issue, we’re continuing our mission to bridge the gap between scientific discovery and real-world application—because true athletic optimization doesn't just happen in the gym... it begins with what we know, and thrives in how we apply it.


My goal with every edition is to connect with forward-thinking coaches, clinicians, and performance professionals who believe in training smarter, recovering better, and pushing limits backed by science—not guesswork. Through this platform, I aim to deliver the latest peer-reviewed research, tools, and frameworks that you can actually use in your programming, coaching, or rehab strategies.


If you haven’t subscribed yet, now’s the time. I promise to continue bringing you evidence-based insights, actionable takeaways, and cutting-edge performance strategies that help you—and those you serve—stay ahead of the game.


Thanks for reading, for growing with me, and for being part of a community that’s redefining what it means to perform at the highest level. Let’s keep moving the field forward—together.


To stronger athletes and smarter science,




-Randy Palacios


Founder, Flexfit Wellness & Recovery


📩 Not subscribed yet? JOIN! never miss a research-backed opportunity to level up.




Wellness Spotlight: Top Recovery Tip of the Month






🦵⚠️Why Your Knee Hates Sharp Cuts: The Hidden Forces Behind ACL Stress After Surgery

Picture this: you’re a year post-ACL reconstruction, laced up, ready to dominate the court or field again. You plant your foot, shift direction—and BAM—that familiar twinge creeps in.


What gives? Aren’t you “cleared”? 💭


Well, science just took a deep dive into exactly what’s happening inside that reconstructed knee during a move we all love (and fear): the side-cut.


And trust me—it’s not just about strength or confidence. It's about physics, forces, and femurs. 🧠⚙️




🎯 The Big Question

“What causes stress on the ACL graft during side-cutting in athletes post-surgery?”


That’s what a group of biomechanical researchers asked—and they answered it using motion capture, force plates, and finite element modeling (basically, 3D simulations for your knee).




🧪 How They Did It

👨🔬 Participants: 8 male athletes, ~1 year post-ACL reconstruction


🎥 Used motion capture and force plates during actual side-cutting drills


🦿 Created subject-specific knee joint simulations


📊 Analyzed stress on the ACL graft in response to different movement patterns


In other words, they built a digital twin of the reconstructed knee to see what really happens when athletes cut left or right.




🧠 The Key Findings (AKA: Why Your ACL Might Be SCREAMING)

🔹 1. Posterior Femoral Displacement = BAD NEWS

When the femur moves backward relative to the tibia, it cranks up stress on the ACL. 👉 Strong correlation with both equivalent and shear stress (r = 0.89 and 0.82)


🔹 2. Ground Reaction Forces Matter

Higher posterior ground reaction forces (when your foot slams into the ground behind your center of mass) = higher ACL stress (r = 0.77) ⚠️ Translation: Stop landing like a freight train.


🔹 3. Knee Extension Moments = More Strain

Greater knee extension torque? More strain on your ACL. This implies that quad-dominant movement patterns could be a problem post-rehab.


🔹 4. Hip Power Helps

A stronger hip extension moment actually reduced ACL shear stress (r = -0.80). 💪 Glutes for the win!



📈 So, What Does This Mean for YOU?

If you're an athlete, rehab pro, or coach, this study shouts one message loud and clear:


🧩 It’s not just about the knee—it’s about how the whole body moves during rapid changes of direction.


✅ Focus on:

Posterior chain strength (glutes & hamstrings)


Reducing aggressive heel strikes and heavy braking


Training hip extension and trunk control


Teaching soft landings and deceleration mechanics


❌ Avoid:

Over-relying on quad-dominant movements


Ignoring side-cut mechanics during return-to-sport testing




💡 Final Whistle: Less Stress, More Success

ACL injuries (and re-injuries) are as much about how you move as how strong you are. This study proves that biomechanics and joint kinematics—especially femur-tibia relationships and hip involvement—make or break your recovery.


👣 Want to get back to cutting with confidence? It might be time to train your mechanics, not just your muscles.


📢 If you’ve been left navigating the recovery maze solo… had guidance that led you in circles… or trusted someone who sidelined your progress—it’s time for a better way forward. 🚀 With over 15 years in the fitness game and 5+ years deep in the trenches of injury recovery and performance rehab, I’ve coached championship-winning NCAA athletes, re-engineered broken movement patterns, and built wellness systems that actually work. Whether you're rebuilding, reloading, or just ready to rise—I'm here to bring elite-level insight, real-world experience, and a personalized touch to your journey.


Let’s turn setbacks into comebacks. Hire me as your Athletic Consultant or Health & Wellness guide, and together, we’ll redefine what’s possible—for you or your team. 💥





Athletic Performance Spotlight: Unlock Your Edge Tip of the Month






🦵💥 One-Leg Wonder or Missed Opportunity? What Science Says About Boosting Jumps with Unilateral Conditioning

Can working one leg really help you jump higher with both? It’s a question strength coaches, rehab specialists, and athletes have asked for years.


So, a group of researchers strapped force plates under 15 trained men, dialed in some serious squatting and jumping, and went to war with this question head-on. 🧪


Let’s break down the findings from one of the most anticipated studies on unilateral conditioning activities (CAs) and their effect on jump performance and limb strength balance.


🧐 Wait, What’s This All About?

It’s called Post-Activation Performance Enhancement (PAPE)—a phenomenon where doing a high-intensity movement (like a heavy squat or jump) “primes” your nervous system to perform better in a related exercise shortly afterward.


Sounds great, right?


But here’s the twist: most studies focus on bilateral (two-legged) movements. This team asked: 👉 “What if we only work one leg? Can that fire up performance for that leg—or maybe even both?”




🎯 The Big Research Goals

Do unilateral isometric or plyometric CAs improve jump height or power output?


Can working just the dominant leg boost the non-dominant leg's performance?


Will this reduce bilateral strength asymmetries that are often linked to injury risk?




🧪 The Experimental Setup

👥 Participants: 15 trained men (6+ years lifting experience)


💪 Three Conditions:


🧠 Measured: Vertical jump height (single leg and CMJ), power output, and strength asymmetry


🕒 Timing: Tested at 3, 6, and 9 minutes post-conditioning




📊 The Results Are In...

🦵 1. Did the Jumps Improve?

NOPE. Neither ISO nor PLY made the dominant leg jump higher. Even bilateral CMJ height and power output remained unchanged.


BUT...


Non-dominant leg jump height did increase—across all three conditions, even in the control group. 🧠 Likely reason? Motor learning. They just got better at jumping with practice—not because of any fancy prep work.




🔄 2. Did Asymmetry Improve?

Also no. Despite working only one leg, there were no changes in bilateral strength balance. So, the dream of correcting limb imbalances with some targeted one-leg CAs? Still on the wishlist.




💡 So… What Does It All Mean?

This study is a reality check: 👉 Just doing three sets of quick one-leg CAs may not “fire up” your performance the way we once hoped—at least not in moderately trained individuals.


💥 But here’s the nuance:


The method matters. Force-focused isometrics vs. high-velocity plyos = different neuromuscular effects.


The athlete matters. Highly trained individuals may benefit more than recreational lifters.


The movement matters. Complexity (like single-leg jumps) may mask subtle improvements.




🧠 Editor’s Take: Motor Learning vs. Muscle Magic

Sometimes, what looks like performance enhancement is just your brain learning to move better. And that’s not a bad thing!


But if your goal is immediate explosive gains, this study reminds us: 🔥 Not all pre-performance rituals are created equal. 💡 For real PAPE benefits, choose the right stimulus, time it smart, and know your athlete’s readiness.




📢 Final Whistle

Is unilateral conditioning a bust? Not necessarily. But this study suggests it might not be your game-changer… yet.


Still, the concept of precision warm-ups, skill sharpening, and limb-specific programming is absolutely worth exploring further—especially with elite athletes or rehab clients.


So before you load up that isometric single-leg squat and expect your vertical to skyrocket… 👉 Consider your training level. 👉 Think about timing and intensity. 👉 And maybe—just maybe—go back to the basics of motor skill refinement.


🎙️ Need help dialing in your warm-up, injury prevention plan, or PAPE strategy? I consult with performance pros, rehab teams, and athletic organizations to bridge the science-to-field gap. Let’s talk!




Mental Performance Spotlight: Mind Over Matter Tip of the Month






🧠🔥 Move Your Body, Prime Your Brain: The Warmup That’s Just Right

We’ve all been there—rolling out of bed for that early workout, mind foggy, body groggy, clinging to coffee like it’s a lifeline. Whether you’re a weekend warrior or a competitive athlete, starting strong matters.


But what if we told you that the key to next-level performance isn’t just about moving your muscles—it's also about firing up your brain?


Welcome to the Goldilocks Zone of Warmups, where not too much, not too little, but just the right amount of brainwork can boost your game. 🧠💪




🕵️♂️ The Study That Put “Thinking While Warming Up” to the Test

Researchers from two independent studies looked at how combining physical AND cognitive exercises during warmup affected performance in two very different groups:


🎾 Young padel athletes


👵 Older adults


And to crank up the challenge? They ran the tests both when participants were well-rested and sleep-deprived.


Why? Because we all know that groggy, low-sleep version of ourselves who shows up at 6 a.m. training...




🎯 The Big Idea: Cognitive Priming + Warmup = Game Changer

We know traditional warmups are great for waking up the body—loosening muscles, activating joints, prepping for motion.


But what if we prepped the brain too? Like a turbo boost for coordination, focus, and reaction time.


This study explored the power of cognitive priming—doing simple but strategic mental tasks during your warmup to unlock better:


Focus 🧘♂️


Reaction time ⚡


Physical performance 💥


And yes—it works even when you're tired. 🤯




🧪 What They Did

Two experimental studies tested three warmup types:


No Warmup 😴


Physical Only 🏃♂️


Physical + Cognitive (Combo) 🧠🏃♀️


Cognitive tasks included things like:


Stroop tests (color-word confusion game)


Psychomotor vigilance tests (reaction-time drills)


Warmups varied from quick (10 min) to longer (17.5 min), and performance was measured in sports tasks (like padel), fitness moves, and mental tests.




📈 What They Found

✅ Sleep-deprived? The combo warmup helps. Participants who were running on low sleep performed better in both sport and cognitive tasks after the combo warmup.


✅ Too much brain work? Performance drops. Longer cognitive sessions during warmup backfired, proving there’s a sweet spot—just like Goldilocks said.


✅ Older adults benefited too. Balance, strength, and attention all got a boost with the combo warmup—even more when sleep-deprived.




🧠💡 Why This Works

It’s called cognitive priming—and it preps your central nervous system for sharper movement, faster decision-making, and better muscle activation. When your brain is alert, your body follows.


But just like in training, more isn’t always better. Overload the brain pre-workout, and you can end up mentally fatigued before you even start.


Hence the “Goldilocks Effect”—the brain warmup has to be just right. ✨




🏁 Takeaway: Prime Your Mind Before You Grind

If you want to level up your performance (especially on low sleep or mentally foggy days), skip the sleepy stretching routine and try this:


Quick, Goldilocks-approved combo warmup:


5 mins of light cardio 🚶♂️


5 mins of bodyweight strength (squats, lunges, arm circles) 💪


5 mins of light brain games (color match, memory tasks, or simple reaction drills) 🧠⚡


Keep it focused, fun, and not too long—and your mind-body system will be game-day ready.




🧬 Editor’s Final Word

Whether you’re coaching a team, training for your next race, or just trying to shake off the Monday blues, cognitive-physical warmups are your secret sauce for sharper, faster, more resilient performance.


Why settle for just warmed up… when you could be fully primed?


💬 Ready to implement this with your team or clients? Let’s connect—I help coaches, therapists, clients and elite athletes design high-performance routines backed by neuroscience.




That’s a wrap on Performance Unchained Insider: From Lab to Locker Room (Edition 9)! 🧠🏋️‍♂️🔥


Thank you for taking the time to dive into this powerhouse issue. Whether it was exploring ACL stress mechanics in side-cutting, unpacking the acute effects of unilateral priming, or rethinking warmups with cognitive activation and the Goldilocks effect—this edition was designed to elevate how you coach, train, and recover using real science with real impact.


If something sparked an idea or challenged the way you think, let’s keep the conversation going. 💬 Drop your thoughts in the comments. 🔁 Share this edition with a colleague, coach, or teammate. 📩 And if you haven’t already, subscribe now to stay connected to a growing community that believes in evidence-backed evolution.


I wholeheartedly promise to continue bringing you the latest, most impactful studies in athletic performance and recovery—delivered with clarity and made for implementation. This is more than a newsletter. It’s a movement to train smarter, recover harder, and think sharper.


Until next time—train smart, recover hard, and stay relentless.


– Randy Palacios


Founder, Flexfit Wellness & Recovery






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From Lab to Locker Room – Performance Unchained Insider (Ed.9)




 
 
 

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