An AI strength & nutrition coach you actually own — evidence-based, safety-first, and free.
FitForge is a collection of Claude skills + a curated knowledge base that turns Claude into a genuinely useful, honest fitness and nutrition coach. No app subscription, no upsells, no "shredded in 30 days" nonsense. Just the boring fundamentals that work, applied to your life, equipment, diet, and schedule.
It's built for everyone: total beginners, returning lifters, busy parents, desk workers, vegetarians and vegans, people training at home with nothing, and folks who just want more energy and fewer aches.
- 🗓️ Builds your training program — periodized, progressive, matched to your goal, equipment, and time.
- 🥗 Coaches your nutrition — calorie & macro targets plus realistic meal plans (incl. veg / Indian / budget options).
- 📈 Runs weekly check-ins — reads your data, adjusts the plan, and keeps you honest.
- 🤸 Fixes your form — cues, common mistakes, and easier/harder variations for any lift.
- 🧠 Builds the habit — behavior design so you actually stick with it past week three.
- 😴 Manages recovery — sleep, stress, soreness, deloads, and "should I train today?" calls.
All of it grounded in a vetted knowledge base, with hard safety guardrails baked into
CLAUDE.md — it knows when to tell you to see a doctor.
git clone https://github.com/<your-username>/fitforge.git
cd fitforge
claude # Claude Code auto-loads CLAUDE.md and the skills in .claude/skills/Then just talk to it:
"I'm a 30yo beginner, 3 days a week, only dumbbells at home, want to build muscle. Build me a plan."
Create a new Project, paste CLAUDE.md into the custom instructions, and upload the
knowledge/ files as Project knowledge. Copy any skill you want from .claude/skills/.
Hook up real data so FitForge stops guessing — wearables (Apple Health, Garmin, Whoop, Strava),
food logging (Open Food Facts, USDA), and tracking (Notion, Google Sheets). See
connections/README.md.
fitforge/
├── CLAUDE.md # The coach's brain: philosophy, safety, how it behaves
├── knowledge/ # Vetted reference the coach reasons from
│ ├── training-science.md
│ ├── nutrition-science.md
│ ├── exercise-library.md
│ └── safety-red-flags.md
├── .claude/skills/ # The skills
│ ├── build-training-program/
│ ├── nutrition-coach/
│ ├── progress-review/
│ ├── form-coach/
│ ├── habit-architect/
│ └── recovery-readiness/
└── connections/ # MCP / integration setup guide
PRs welcome — new skills, better exercise cues, regional meal templates, translations, more
connections. Keep two rules: (1) evidence-based, and (2) safety-first (read the guardrails
in CLAUDE.md). Cite sources for any factual claims in the knowledge base.
FitForge is open-source educational software, not medical advice. It does not diagnose, treat, or prescribe. Always consult a qualified physician, physiotherapist, or registered dietitian before starting any exercise or nutrition program — especially if you have a health condition, are pregnant, or are returning from injury.
MIT — see LICENSE. Build on it, remix it, share it.