Endofibrosis is a rare vascular condition characterised by progressive thickening of the intimal layer of an artery, leading to luminal narrowing and impaired blood flow. It is clinically significant because it can cause exercise-induced limb ischaemia, particularly in young athletes, resulting in pain and reduced performance. A key association is its prevalence in cyclists, where repetitive hip flexion contributes to arterial injury and subsequent endofibrotic changes.