Custom GPTs = Personalized Health Coaches

Imagine having a coach who knows your diet style, your workout preferences, your fitness goals—and never takes a day off. That’s what a Custom GPT can become. This is how I created EddyGunz.AI my custom AI used in the latest F45 Challenge (q1 2025).

If you’ve got the $20/month ChatGPT Plus plan, you already have access to this game-changing feature. Here’s how to use it to build your own AI health coach.

What’s a Custom GPT?

A Custom GPT is a specialized version of ChatGPT that’s designed to focus on a particular goal—like fat loss, plant-based eating, or high-protein meal planning. You can either build your own or explore ones created by others.

Think of it as a chatbot that knows your vibe.

Why It’s Useful for Fitness and Nutrition

  • Tailored advice based on your goals

  • Remembers your preferences

  • Faster responses (less repeating yourself)

  • Can include links, tools, and file uploads specific to your lifestyle

Step-by-Step: How to Build or Find a Custom GPT

Option 1: Use an Existing GPT

  1. In the ChatGPT interface, click “Explore GPTs”

  2. Search for terms like:

    • Macro Coach

    • Meal Planner

    • Fitness Buddy

    • Keto Meal Assistant

  3. Test a few to see what fits your needs.

Pro Tip: Favorite the best ones so they show up at the top of your app.

Option 2: Build Your Own

  1. Click “Explore GPTs” > “Create a GPT”

  2. Follow the walk-through or use this starter intro prompt:

“You are a PhD level expert in cutting-edge custom fitness and nutrition coaching with an expertise that makes you a high-demand guru for many celebrity clients. You now work for a 42-year-old male doing HIIT workouts 4x/week, eating a high-protein, lower-carb diet, with occasional travel and limited kitchen access. Recommend realistic meals and give me advice on recovery, nutrition, supplementation based on the latest research, and mindfullness for sleep. I will provide you with metrics from other devices as input. Use this input to track my progress. Keep the tone friendly but informed.”

  1. Add custom instructions (like goals, macros, preferences, restrictions, etc.)

  2. Save it and name it something like Coach Gunz or Macro Machine

Now, it’s YOUR coach—trained on YOUR life.

What Can You Ask Your Custom GPT?

  • “Give me a 5-day meal plan with 160g of protein/day under 2,000 calories with items I can purchase from Trader Joe’s.”

  • “What’s a hotel-room workout I can do in 20 minutes that focuses on cardio?”

  • “Here’s my workout schedule for the week—can you optimize it for fat loss?”

  • “Suggest healthy meals I can cook in 20 minutes or less with this photo of ingredients.”

Bonus Tip: Give It a Personality

Want a no-nonsense coach? Or a laid-back nutritionist who talks like your best friend? You can describe the tone you want in the setup. It makes the responses way more fun and tailored.

Try This Now:

  1. Go to ChatGPT > Explore GPTs > Create a GPT

  2. Use the sample coach prompt above to build your AI fitness assistant

  3. Ask it: “Build me a high-protein grocery list for under $75.”

Edward Tatton