The Science of the Golf Swing: Center of Mass, Fascia & Speed with Davide Bertoli

The Science of the Golf Swing: Center of Mass, Fascia & Speed with Davide Bertoli

Author: Mark Immelman June 3, 2026 Duration: 49:51

In this episode of On The Mark, host Mark Immelman is joined by David Bertoli (aka “Davide”) for a deep, visual-first breakdown of how the golf swing actually works in 3D—not as frozen “positions,” but as moving phases driven by what the body is doing internally.

David shares how his team built a 3D system that reveals the skeleton, muscles, and fascia in motion—so golfers and coaches can stop chasing a Rory/McIlroy “look” and start optimizing their movement pattern.

A major focus is David’s framework: the Six Phases of the Golf Swing, built around Center of Mass (COM) movement + Anatomy Trains / fascia chains. They explore why the pelvis is the engine, how COM moves (horizontally and vertically), why maximum unweighting matters for speed, and how “carefree” phase-based movement beats “careful” position-chasing every time.

In This Episode, You’ll Learn:

  1. ✅ Why 3D changes everything: stop studying the club “outside,” start understanding the body “inside”
  2. ✅ The difference between positions vs phases (and why a golf swing is a “moving sculpture”)
  3. ✅ What Center of Mass actually is, where it sits, and why the pelvis is so tied to it
  4. ✅ How COM moves in an “almost infinity-sign” pattern (and why it anticipates the club)
  5. ✅ Why elite players get lower than address in transition (and how that fuels speed)
  6. ✅ What fascia is (and why the body is a “full web”) + how anatomy chains store/release energy 
  7. ✅ The Six Phases: from address → shaft parallel → pelvis rotation → top → max unweighting → impact → hands chest-high
  8. ✅ A huge myth at impact: why you should not try to open shoulders as much as the ribcage, and
  9. ✅ The “eccentric load” trio: core stretch, lead-shoulder stretch, lead-wrist stretch (and why thoracic rotation matters.) 

Key Takeaways

  • Stop copying positions. Many great swings look different—but the best swings move through similar phases.
  • Pelvis movement predicts swing quality. If the pelvis (and COM) moves well, the rest organizes more naturally. 
  • Speed requires going down before going up. The best players drop lower than address, then push up fast into impact.
  • Fascia matters. Efficient golf is stored energy → redirected forces → released energy, not “hit the ball harder.”
  • Carefree beats careful. When golfers chase positions, they get tense; when they move through phases, they flow. 

After you have listened to this podcast, go to YouTube, search and subscribe to Mark Immelman and watch the show to see David's graphics and presentation of his golfswing research and how his "Phases of the Swing" work.


Mark Immelman brings a rare perspective to the On the Mark Golf Podcast, shaped by his own journey from college coach to broadcaster and instructor. Here, conversations go far beyond simple swing tips. Each episode feels like a deep dive into the ecosystem of elite golf, facilitated by Immelman’s genuine curiosity and deep knowledge. You’ll hear PGA TOUR players unpack the specific decisions behind crucial shots, while swing coaches break down the mechanics in accessible language. But the discussion doesn’t stop there. Caddies share their strategic roles, fitness experts explain the foundations of power, and mental coaches offer tools for the psychological game. This podcast, presented by the PGA TOUR, provides a comprehensive look at what it truly takes to excel, from equipment nuances to the unspoken pressures of competition. It’s that blend of technical insight and personal storytelling, gathered from the very best minds in the sport, that can genuinely change how you think about and play the game. Whether you're a seasoned player or a dedicated fan, these conversations offer a unique, inside-the-ropes education you won’t find anywhere else.
Author: Language: English Episodes: 100

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