# ExRL: Sample-Efficient Online Adaptation of Long-Chunk Policies via Execution Length Control > Source: > Published: 2026-11-11 04:00:22+00:00 Predicting long action chunks, often spanning dozens of timesteps, has become a key ingredient in increasingly capable robot policies. In this paper, we find that adapting these long-chunk policies with existing reinforcement learning (RL) methods can require many online samples due to the high dime