Just Fly Performance Podcast

Just Fly Performance Podcast


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

October 16, 2025

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,...