How to use ChatGPT for fitness

Updated

Can ChatGPT be your personal trainer?

For general advice, yes. ChatGPT can write a training plan, explain an exercise or adjust a workout in seconds. Where it falls short is your history: on its own it doesn't know what you lifted last week, how you slept or what your heart rate is doing, so its plan is a well-written guess. Fix that by connecting a training app. With Mobela connected, ChatGPT reads your real workouts, runs and recovery, and can save the workouts it builds straight to the Mobela app on your phone.

ChatGPT prompts for workouts that actually work

The more specific you are about your age, schedule, equipment and goal, the better the plan. Copy one of these and change the details:

  1. "I'm 34, I can train 3 days a week for 45 minutes at a gym. Build me a 6-week strength plan with sets, reps and how to progress each week."
  2. "I want to run my first 10K in 8 weeks. I can run 3K now. Write a plan with 4 runs a week, and tell me which ones should be easy."
  3. "My lower back gets tight after deadlifts. What are 3 form fixes to try, and when should I see a physio instead?"
  4. "I slept 5 hours and feel flat. Should I still do today's heavy leg day? Give me a lighter version if not."
  5. "Swap the exercises in this workout for ones I can do at home with two dumbbells: [paste workout]."

What ChatGPT can't do on its own

  • It doesn't know what you lifted last week, so it can't tell you what weight to beat today.
  • It can't see your sleep, resting heart rate or recent runs, so it can't tell when you need an easy day.
  • Every plan starts from what you remember to type in, and the chat history isn't a training log.

How to give ChatGPT your real training data

Add Mobela as a custom connector in ChatGPT's settings, using the server URL https://mobela.app/mcp, then sign in with your Mobela account. Custom connectors may need a paid ChatGPT plan or developer mode. Full steps: connect Mobela to your AI assistant.

Once it's connected, ChatGPT sees what Bela, Mobela's AI coach, sees: your lifts, runs, sleep and heart rate, plus the notes Bela keeps about you, like an injury, a race date or an exercise you won't do. So the plan it writes skips the lunges that bother your knee without you having to say so again.

Try: "Check my Mobela coach notes and last month of training, then tell me what to focus on" or "Build me a push/pull/legs week based on what I lifted last week and save it to my Mobela favorites."

What is Mobela?

Mobela is a free iPhone and Android app that keeps every walk, run, ride and lift in one log, with Bela, an AI coach that remembers your history, and a feed built for friends instead of leaderboards. It syncs from Garmin, Apple Health, Health Connect and Strava, and connects to Claude, ChatGPT and Grok.

Mobela is invite-only for now. Join the waitlist and we'll email your invite.