Complex sentence: He began his career in horse racing as a teenager working as a hotwalker & groom and rode is bicycle in the early morning hours to Ak-Sar-Ben racetrack in Omaha.
Split into simpler sentences: He began his career in horse racing as a teenager working as a hotwalker & groom. He rode is bicycle in the early morning hours to Ak-Sar-Ben racetrack in Omaha.