Final answer:
The reading does not provide a specific statistic about the number of transmasculine individuals who experienced one physical negative outcome attributed to binding.
Step-by-step explanation:
According to the reading “Health Impact of Chest Binding Among Transgender Adults,” it does not specify the exact number of transmasculine people who experienced one physical negative outcome attributed to binding. The reading discusses the health impact of chest binding, including potential negative outcomes such as skin issues, breathing difficulties, and muscle pain. However, it does not provide a specific statistic about the number of transmasculine individuals who experienced these negative outcomes.