How to create your own AI performance coach: Optimizing your unique nutrition, recovery, and injury management needs | Lucas Werthein (Cactus)

Lucas Werthein, the COO and co-founder of Cactus, shares how he built a personalized AI wellness coach using ChatGPT to optimize his athletic performance while managing past injuries. After multiple surgeries on his knees, shoulder, and foot, Lucas created a system that synthesizes data from medical imaging, blood tests, wearable devices, and nutrition plans to provide personalized recommendations. His AI coach helps him balance competitive tennis, weightlifting, and running a company while maintaining his goal of “feeling 25 in a 40-year-old body.” Lucas demonstrates how this approach transforms siloed health information into actionable insights that protect joints, optimize recovery, and extend peak performance. What you’ll learn: - How to configure a ChatGPT with multiple data types, including MRIs, x-rays, blood tests, and wearable metrics, to create a comprehensive health profile - A framework for setting clear performance boundaries that prioritize joint protection, energy optimization, and injury prevention - Techniques for using AI to balance nutrition around special events like social dinners while maintaining performance goals - How to use images and videos to get AI feedback on physical symptoms and injury recovery timelines - A method for validating and contextualizing medical advice by having AI synthesize information from multiple health-care providers - Why creating clear rules and anti-prompts helps AI deliver practical, evidence-based recommendations instead of trendy supplements or extreme protocols — Copy Lucas’s Health Coach Prompt: https://www.lennysnewsletter.com/p/how-to-create-your-own-ai-performance-coach — Brought to you by: WorkOS—Make your app enterprise-ready today Google Gemini—Your everyday AI assistant — Where to find Lucas Werthein: Website: https://cactus.is/ — Where to find Claire Vo: ChatPRD: https://www.chatprd.ai/ Website: https://clairevo.com/ LinkedIn: https://www.linkedin.com/in/clairevo/ X: https://x.com/clairevo — In this episode, we cover: (00:00) Introduction to Lucas’s athletic background and injury history (04:55) The challenge of synthesizing siloed health data (06:11) Building a GPT to optimize performance and recovery (09:57) Demonstrating the data types integrated into the AI coach (13:54) Configuring the GPT with clear performance goals and boundaries (16:31) Setting realistic expectations for the AI coach (17:50) Creating nutrition, training, and recovery frameworks (21:47) Establishing hard boundaries and anti-prompts (24:25) Example: Managing nutrition around special events (27:30) Accessibility and affordability of on-demand coaching (28:24) Practical examples and real-life scenarios (29:31) Using AI for injury management and recovery planning (34:19) Validating expert opinions and translating medical advice (37:25) Vision for the future of AI in personal health coaching (43:27) Other AI workflows: synthetic clients and AI co-founders (48:48) Final thoughts on AI reliability and evolution — Tool referenced: • ChatGPT: https://chat.openai.com/ — Other references: • InBody scan: https://inbodyusa.com/ • Whoop: https://www.whoop.com/ — Production and marketing by https://penname.co/. For inquiries about sponsoring the podcast, email [redacted email].