Skip to main content
How I AI

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

51 min episode · 2 min read
·
Lucas Werthein

Episode

51 min

Read time

2 min

Topics

Health & Wellness, Remote Work, Leadership

AI-Generated Summary

Key Takeaways

  • Multi-format data integration: ChatGPT processes MRIs, X-rays, blood tests in PDF format, CSV files from wearables, nutrition plans, and journal entries across multiple languages without requiring data cleaning or standardization, enabling comprehensive health synthesis.
  • Prompt architecture for coaching: Effective GPT prompts combine role definition, realistic outcome goals, hard boundaries on what not to recommend, tone specifications, and cross-validation requirements rather than demanding extreme optimization or unproven biohacking interventions.
  • Visual input for diagnosis: Taking photos or videos of pain points, circling specific areas, and uploading to ChatGPT enables on-demand validation of expert opinions and personalized explanations in accessible formats when medical professionals are unavailable.
  • Synthetic expert workflows: Creating GPTs trained on publicly available information about clients or colleagues enables teams to get 80-90% accurate responses to questions when those experts are unavailable, reducing meeting overhead in distributed work environments.

What It Covers

Lucas Werthein demonstrates how he built a custom ChatGPT performance coach using MRIs, blood tests, WHOOP data, nutrition plans, and injury records to optimize athletic performance, recovery, and injury management at age 40.

Key Questions Answered

  • Multi-format data integration: ChatGPT processes MRIs, X-rays, blood tests in PDF format, CSV files from wearables, nutrition plans, and journal entries across multiple languages without requiring data cleaning or standardization, enabling comprehensive health synthesis.
  • Prompt architecture for coaching: Effective GPT prompts combine role definition, realistic outcome goals, hard boundaries on what not to recommend, tone specifications, and cross-validation requirements rather than demanding extreme optimization or unproven biohacking interventions.
  • Visual input for diagnosis: Taking photos or videos of pain points, circling specific areas, and uploading to ChatGPT enables on-demand validation of expert opinions and personalized explanations in accessible formats when medical professionals are unavailable.
  • Synthetic expert workflows: Creating GPTs trained on publicly available information about clients or colleagues enables teams to get 80-90% accurate responses to questions when those experts are unavailable, reducing meeting overhead in distributed work environments.

Notable Moment

Werthein uploads pre-surgery and post-surgery knee MRIs alongside real-time injury photos and PT prescriptions, allowing his AI coach to provide recovery timelines and validate medical advice with visual context that typical health apps cannot process.

Know someone who'd find this useful?

Episode Transcript

I have always been super active into sports, really constantly pushing myself to the limits of what my body can do. And, naturally, that means injuries. Right? And for me, it became a little bit too much. And so as soon as ChatGPT launched, I started experimenting with aggregating this data so that I can get a more clear synthesis of what I can do to actually optimize the body. One of the things that I have never seen anybody do yet, I've seen a lot of folks drop in their daily workouts or their food diaries, but I have not seen MRIs and imaging here. And what important context for somebody who's an athlete to say, not only is this how I'm performing on an output basis, but this is actually, under the hood. So it's really interesting that combination of data into these files. I'm wanting to demand of my body to feel like 25 in a 40 year old's body. And it's interesting to think what if every person could have a coach that organizes all this action into clarity. Right? And part of what we've been talking about is that not everyone is looking for this type of performance. Most people don't need six packs or match prep, but they could use help with the basics. Right? Eating less, processed food, sleeping better, moving more. And I think an AI coach could meet people where they are and actually give them the necessary nudges and contextualization of information that they need to be a better version of themselves. Welcome back to How I AI. I'm Claire Vaux, product leader and AI obsessive here on a mission to help you build better with these new tools. Today, we have Lucas Wertheim, head of technology at Cactus, who has done work for basically everybody, Apple, Coca Cola, MTV, and even Beyonce herself. But today, we're not gonna talk about product development. We're gonna talk about how Lucas has built a wellness coach inside ChatGPT to optimize his nutrition, his workouts, and keep him feeling 25 even though he's a little bit older than that. This is a really fun episode with some practical insights for people just trying to make their lives better with AI. Let's get to it. This episode is brought to you by WorkOS. AI has already changed how we work. Tools are helping teams write better code, analyze customer data, and even handle support tickets automatically. But there's a catch. These tools only work well when they have deep access to company systems. Your copilot needs to see your entire code base. Your chatbot needs to search across internal docs. And for enterprise buyers, that raises serious security concerns. That's why these apps face intense IT scrutiny from day one. To pass, they need secure authentication, access controls, audit logs, the whole suite of enterprise features. Building all that from scratch, it's a massive lift. That's where WorkOS comes in. WorkOS gives you drop …

Get the full transcript (8,738 words) + summary by email — free

One-time email with the complete transcript and AI summary of this episode. No account needed.

One email, no spam. We’ll also show you what SignalCast does.

Browse all How I AI transcripts →

You just read a 3-minute summary of a 48-minute episode.

Get How I AI summarized like this every Monday — plus up to 2 more podcasts, free.

Pick Your Podcasts — Free

Keep Reading

Books, tools, and gear mentioned in this episode

SignalCast may earn commission on purchases via these links. As an Amazon Associate, SignalCast earns from qualifying purchases.

Tools

  • by OpenAI

    Lucas Werthein demonstrates how he built a custom ChatGPT performance coach using MRIs, blood tests, WHOOP data, nutrition plans, and injury records to optimize athletic performance, recovery, and injury management at age 40.

Gear

  • by WHOOP

    Lucas Werthein demonstrates how he built a custom ChatGPT performance coach using MRIs, blood tests, WHOOP data, nutrition plans, and injury records to optimize athletic performance, recovery, and injury management at age 40.

More from How I AI

We summarize every new episode. Want them in your inbox?

Similar Episodes

Related episodes from other podcasts

Explore Related Topics

This podcast is featured in Best AI Podcasts (2026) — ranked and reviewed with AI summaries.

Read this week's Health & Longevity Podcast Insights — cross-podcast analysis updated weekly.

You're clearly into How I AI.

Every Monday, we deliver AI summaries of the latest episodes from How I AI and 192+ other podcasts. Free for one show.

Start My Monday Digest

No credit card · Unsubscribe anytime