In this episode of The Feldman Protocol, can elite athletes truly thrive on fat alone — with zero carbs? Dave sits down with Casey Ruff (personal trainer, nutrition coach, and host of Boundless Body Radio) to explore his journey from gym kid to keto rebel, high-intensity training principles, a rogue low-carb experiment inside a corporate fitness company that produced 732 lbs of fat loss, the LMHR study saga, carnivore adaptation and anxiety relief, and a surprising email from the American Heart Association.

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Website: `https://thefeldmanprotocol.com`

⏱ Chapters

3:17 – Casey's ice hockey obsession

8:05 – A punch that changed everything

12:38 – Two years in Brazil as a missionary

17:03 – From architecture dreams to personal training

21:06 – Finding his calling at the gym

28:51 – High intensity training explained

36:57 – Why sport-specific training is a myth

39:02 – Metabolic carts & the RER deep dive

43:01 – The Biggest Loser metabolic damage case

46:24 – Calories in/out: why it failed everyone

50:25 – Nina Teicholz & The Big Fat Surprise

54:07 – Bonking, glycogen, and fat adaptation

58:10 – Butter-fed athletes & the keto revelation

1:04:13 – Casey's fasted hockey game story

1:06:07 – Going rogue with Diet Doctor meal plans

1:14:02 – Getting the nutrition certification

1:17:17 – The contest winner who changed everything

1:20:19 – 732 lbs lost, 98.1% from fat

1:27:33 – Did results hold after the contest?

1:33:27 – Starting Boundless Body podcast in 2020

1:41:25 – On being a natural podcast host

1:52:17 – The pandemic pivot to virtual training

1:59:08 – Carnivore and the vanishing anxiety

2:04:31 – The LMHR Match Analysis saga begins

2:16:26 – Low Carb Denver 2023 collective gasp

2:23:22 – Dave reveals new Heartflow re-analysis

2:29:35 – The movie & Robin's bipolar decision

2:31:37 – The AHA misinformation email

2:42:14 – Prepping for Arthur Agatston

2:48:42 – Fat adaptation and hockey performance

2:55:39 – Travel strategies: fasting vs. carnivore snacks

2:59:08 – Changing his mind: strict carnivore or not?

3:05:36 – Where to find Casey

#FeldmanProtocol #DaveFeldman #CaseyRuff #LowCarbLife #KetoDiet #CarnivoreDiet #FatAdaptation #HighIntensityTraining #LMHRStudy #CholesterolCode #MetabolicHealth #SeedOils #HeartHealth #NutritionCoach #EnduranceSport #BloodWork #Ketosis #BoundlessBodyRadio