485: James de Lacey on Rhythm, Reactivity, and the Art of Athletic Power

Today’s guest is James de Lacey. James is a professional strength and conditioning coach and the founder of Sweet Science of Fighting, a leading platform for combat sports performance. He has coached in professional rugby leagues across New Zealand, Europe, and the United States, and has trained athletes in MMA, boxing, Muay Thai, and BJJ. Through Sweet Science of Fighting, he delivers evidence-based programs and education for fighters and coaches worldwide. Strength training for athleticism typically focuses on sets, reps, and general forces, but rarely gets into aliveness and skill management of the resistance itself. The former is great for building basic physical competencies, but in integrating the latter, we can breathe more life into a performance program. On today’s show, we dive into James' approach to building athletic strength and power across multiple mediums. We explore how Olympic lifting, especially pull variations, connects to real sport actions, and how striking and collision sports highlight the importance of timing, rigidity, and effective mass. We also break down resistance methods like oscillatory work, flywheels, and accentuated eccentrics, focusing on their alive, reactive qualities rather than just load. These principles carry into speed and power training, including plyometrics and sprinting, with rhythm and movement quality as a central theme. The episode makes strong connections between field sports and combat sports, showing how momentum, relaxation, and rigidity at impact shape performance. Today’s episode is brought to you by Hammer Strength and LILA Exogen wearable resistance. Use the code “justfly20” for 20% off any Lila Exogen wearable resistance training, including the popular Exogen Calf Sleeves. For this offer, head to Lilateam.com Use code “justfly10” for 10% off the Vert Trainer View more podcast episodes at the podcast homepage. (https://www.just-fly-sports.com/podcast-home/) Timestamps 0:56 - Olympic Lifting Philosophy and Sport-Specific Implementation 4:26 - The Role of Bar Flex and Slack in Block Pulls vs. Rack Pulls 7:03 - High Block Work for Impulse and Technical Refinement 12:22 - Oscillatory Training and the Limits of Maximal Strength 24:49 - Upper/Lower Body Dissociation for Fluid Movement and Game Speed 52:25 - Controlled Eccentric Overload using Flywheel Technology Actionable Takeaways 0:56 - Olympic Lifting Philosophy and Sport-Specific Implementation Prioritize Pull Variations: Use variations like the high pull, especially in combat sports (grapplers), to strengthen the upper back and facilitate violent, vertical hip extension. This is useful for actions like a mat return. Select Snatch over Clean: Choose snatch variations (e.g., power snatch from the hip/hang) over the clean for general athletes because the front rack position is often too difficult, making the snatch easier to learn. Match Lift to Resource/Context: Recognize that the implementation of Olympic lifts in a team setting is often constrained by equipment (e.g., only two barbells for a team) and the athlete's level. 4:26 - The Role of Bar Flex and Slack in Block Pulls vs. Rack Pulls Understand Sensory Differences: Recognize that pulling from blocks feels different than pulling from a power rack. Blocks hold the plates, allowing for "slack" and "flex" in the bar, similar to a deadlift bar. Avoid Dead Weight: Pulling from a rack holds the bar and removes the flex, creating a "dead weight" stimulus, which makes the lift harder and limits the use of bar properties to set positions. 7:03 - High Block Work for Impulse and Technical Refinement Train for Time Constraints: Utilize high block work to force athletes to generate high impulse in very short time frames, mirroring the time constraints often encountered in sport. Force Pull-Under Technique: High blocks are a beneficial constraint that forces the athlete to actively "pull themselves under" the bar, addressing a common technical flaw where athletes dive under instead of finishing the pull. Facilitate Speed via Relaxation: Understand that successful Olympic lifting requires a "pseudo activation relaxation kind of thing," where relaxation facilitates the speed needed to pull under the bar. 12:22 - Oscillatory Training and the Limits of Maximal Strength Use Oscillatory Isometrics: Implement oscillatory or pulse-style isometric exercises, such as a pulsing single-leg glute ham raise isometric, for specific adaptations (e.g., in-season hamstring work). Re-evaluate Max Strength Bias: Understand that an over-emphasis on maximal strength may not transfer to improved power in short time frames. Research suggests that "relaxation kinetics" can be negatively adapted by heavy strength training alone, causing athletes to "break earlier" in fast, cyclical actions. Prescribe by Sport Demands: Group athletes by position or sport needs: grapplers need high force; strikers need high velocity; rugby backs need speed; tight five need strength; and adjust the volume of maximal strength work accordingly. 24:49 - Upper/Lower Body Dissociation for Fluid Movement and Game Speed Prioritize Dissociation: View the ability to rapidly dissociate the upper and lower body as a key component of athleticism. Implement Dissociation Drills: Use large association exercises, such as the landmine bar whip drill combined with foot switching, which James has observed good athletes doing well. Use Perturbation for Game Speed: Apply upper-body perturbations like a "halo acceleration run" (sprinting while haloing a 5kg plate above the head) to help athletes maintain speed while doing an upper-body task. Relate to Game Actions: Connect dissociation training to "critical game speed" examples, such as a rugby or soccer player looking behind them to track a ball while sprinting in a straight line. 52:25 - Controlled Eccentric Overload using Flywheel Technology Use Machines for Eccentric Overload: Leverage machines like the 1080 Quantum for eccentric overload, as it provides a safe, controlled method that overcomes the limitations (heavy loads, multiple spotters, danger) of traditional eccentric lifting. Test Extreme Applications: Controlled mechanical resistance can be used for novel training; James tested using the Quantum for eccentric overload neck training (40 kgs on an Iron Neck) and found no soreness, suggesting safety with constant feedback loops. Apply to Sport-Specific Movements: Eccentric overload can be applied to sport-specific movements like "bear hug rotations" (resisting the machine as it pulls a bag back) for huge transfer to grappling, wrestling, and rugby. About James de Lacey James de Lacey is a professional strength & conditioning coach and the founder of Sweet Science of Fighting, a leading platform for combat sports performance education. He holds a Master’s degree in Sport & Exercise Science and has worked as an S&C coach in professional rugby leagues across New Zealand, Europe, and the United States, as well as with MMA, boxing, Muay Thai, and BJJ athletes. Through Sweet Science of Fighting, he creates evidence-based programs, courses, and research breakdowns focused on strength, power, conditioning, and technical performance for fighters and coaches. His work bridges sports science with the practical demands of combat sports, making high-level training methods accessible and applicable worldwide.