In this blog post, Philipp Kahr explores the optimization of data collection from Strava using a custom script integrated with Elastic APM for enhanced observability. Strava, a popular platform for athletes, allows users to sync data from devices like Apple Watch and Garmin, and this script facilitates the extraction of fitness data to gain insights into one's fitness journey. The post delves into the script's functionality, which includes retrieving activities via the Strava API and processing them for storage in Elasticsearch. It emphasizes the importance of understanding where time is spent in the script, particularly whether delays occur during API calls or data uploads, and addresses these issues by incorporating Elastic APM for performance monitoring. The post provides guidance on setting up APM, including importing the necessary libraries and instrumenting key transactions within the script to monitor performance metrics. The blog series also invites readers to explore previous and upcoming posts for a comprehensive understanding of utilizing the Elastic Stack with Strava data.