Background:The classic injury mechanism of a distal biceps brachii tendon rupture (DBBTR) is eccentric loading to the flexed elbow when the forearm is supinated.Purpose:To determine alternative mechanisms of a DBBTR in powerlifting sports, particularly in deadlift competitions, with the use of YouTube videos.Study Design:Descriptive epidemiology study.Methods:A search on YouTube was performed using the search terms “distal biceps tendon rupture” and “distal biceps tendon injury” combined with “competition,” “deadlift,” and “powerlifting.” The videos underwent an evaluation for accuracy by 3 surgeons according to predetermined criteria. Type of sports activity, participant sex, side of the injury, and arm positions at the time of the injury were recorded.Results:Among the videos reviewed, 35 injuries were found appropriate for an evaluation. All participants were male. The majority of the injuries (n = 25) were observed during the deadlift. Only in 1 deadlift injury were both forearms in supination. In the remaining deadlift injuries (n = 24), all elbows were in extension, with 1 forearm in supination and the other in pronation. Among the deadlift injuries in the mixed-grip position, all ruptures occurred in a supinated extremity: 25% (n = 6) of ruptures occurred on the right side, and 75% (n = 18) of ruptures occurred on the left side; this was a significant difference (P = .014).Conclusion:We described an alternative mechanism for a DBBTR, namely, eccentric loading to an extended elbow when the forearm is supinated during the deadlift. As all the ruptures occurred in a supinated extremity, holding the bar with both forearms in pronation may prevent or decrease the risk of ruptures during the deadlift.