Blog
AI insights, evidence-based training science, and the engineering behind Arvo.
AIPersonal TrainingOpinion
Can AI Replace a Personal Trainer? An Honest Assessment
AI workout apps are getting smarter, but can they truly replace a human coach? We break down what AI does better, where coaches still win, and who benefits most from each.
March 2026
10 min read
Read TrainingData AnalysisMistakes
Why You're Not Making Progress: 7 Mistakes We See in User Data
Analyzing anonymized workout data from thousands of Arvo users reveals 7 patterns that stall muscle growth.
March 2026
14 min read
Read EngineeringCost OptimizationAI
We Cut AI Costs by 54% Moving to GPT-5.4-mini
A practical guide to migrating from GPT-4o to GPT-5.4-mini/nano while maintaining quality. Cost routing, prompt restructuring, and the tradeoffs we made.
March 2026
10 min read
Read ArchitectureAICost Optimization
How I Built a Real-Time Periodization Engine Using Multi-Agent AI
Orchestrating 30+ specialized AI agents to generate adaptive training programs. Cost routing, prefix caching, and the mistakes I made along the way.
March 2026
12 min read
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