The sport of triathlon involves three different endurance sports: swimming, biking, and running. Cross-training allows the athlete to train for one sport while resting from another. The repetitive motions required for each sport may lead to overuse and injury. The purpose of this study was to examine musculoskeletal injury incidence in amateur triathletes to determine if these injuries caused lost time from training, racing, working, or daily functioning. Seventy-two recipients responded to survey items that gathered information about demographics, sports participation, and musculoskeletal injury occurrence and interference with sports participation, work, and daily activities. Three-quarters sustained triathlon-related musculoskeletal injuries during training due to overuse. A majority experienced training interruption and interference with daily functioning and sought professional help for their injuries. Little information is available on the treatment of musculoskeletal injuries in triathletes. This survey raises important clinical implications for physical therapists. Further exploration of overuse injury incidence is warranted in this population.