PlanFitting: Personalized Exercise Planning with Large Language Model-driven Conversational Agent
Donghoon Shin, Gary Hsieh, Young-Ho Kim
TL;DR
This work tackles the challenge of creating personalized, actionable exercise plans without ongoing expert involvement. It introduces PlanFitting, an LLM-driven conversational agent that collects user goals, availability, and obstacles through natural dialogue and generates weekly plans grounded in established guidelines via implementation intentions. The system combines retrieval-augmented generation from a curated exercise dataset with a dual-LMM pipeline (dialogue generation and plan synthesis) and a dashboard to track constraints and progress. Evaluation across a formative study, a user study (N=18), and expert assessments shows plans that adhere to guidelines and are perceived as useful and actionable, while highlighting areas for improving balance across exercise types and intensity. The findings offer actionable insights for designing scalable, domain-grounded conversational planning assistants and point to broader applicability in other planning domains and long-term use scenarios.
Abstract
Creating personalized and actionable exercise plans often requires iteration with experts, which can be costly and inaccessible to many individuals. This work explores the capabilities of Large Language Models (LLMs) in addressing these challenges. We present PlanFitting, an LLM-driven conversational agent that assists users in creating and refining personalized weekly exercise plans. By engaging users in free-form conversations, PlanFitting helps elicit users' goals, availabilities, and potential obstacles, and enables individuals to generate personalized exercise plans aligned with established exercise guidelines. Our study -- involving a user study, intrinsic evaluation, and expert evaluation -- demonstrated PlanFitting's ability to guide users to create tailored, actionable, and evidence-based plans. We discuss future design opportunities for LLM-driven conversational agents to create plans that better comply with exercise principles and accommodate personal constraints.
