Given the task definition, example input & output, solve the new input case.
Given an abstract, indicate which of the provided candidate titles (Option1 and Option2) best describes it (respond with the text of the title, not option1/2).
Example: Abstract: Some patients converted from ventricular fibrillation to organized rhythms by defibrillation-trained ambulance technicians (EMT-Ds) will refibrillate before hospital arrival. The authors analyzed 271 cases of ventricular fibrillation managed by EMT-Ds working without paramedic back-up. Of 111 patients initially converted to organized rhythms, 19 (17%) refibrillated, 11 (58%) of whom were reconverted to perfusing rhythms, including nine of 11 (82%) who had spontaneous pulses prior to refibrillation. Among patients initially converted to organized rhythms, hospital admission rates were lower for patients who refibrillated than for patients who did not(53% versus 76%, P = NS), although discharge rates were virtually identical (37% and 35%, respectively). Scene-to-hospital transport times were not predictively associated with either the frequency of refibrillation or patient outcome. Defibrillation-trained EMTs can effectively manage refibrillation with additional shocks and are not at a significant disadvantage when paramedic back-up is not available.
Which is the apt title for the abstract? option1: Refibrillation managed by EMT-Ds option2: Maintenance of compliance in a small diameter arterial prosthesis.
Output: Refibrillation managed by EMT-Ds
The abstract is about refibrillation and it is also mentioned in the abstract that it is managed by EMT-Ds. So it is an apt title.

New input case for you: Abstract: Because female gymnasts as a group display higher than average incidences of stress-related pathologies of the lumbar spine, it was of interest to evaluate mechanical factors which are potential contributors. Lumbar hyperextension and impact forces were quantified for performances of five commonly executed gymnastics skills by four competitive collegiate women gymnasts. The skills performed were the front walkover, the back walkover, and the front handspring, the back handspring, and the handspring vault. Wielke's (1983) radius method was used to quantify lumbar curvatures from film data during normal relaxed standing postures and during subject performances of the five selected skills. A force platform was used to monitor vertical and lateral ground reaction forces at the terminations of the respective skill performances. Of the skills examined, the handspring vault produced the highest vertical and lateral impact forces, and the back handspring and back walkover required the greatest amounts of lumbar hyperextension. During the front and back walkovers and during the back handspring, maximum lumbar hyperextension occurred very close to the time that impact force was sustained by either the hands or the feet.
Which is the apt title for the abstract? option1: Mechanical contribution to lumbar stress injuries in female gymnasts. option2: Mediastinal vessels: postoperative evaluation with MR imaging.
Output:
Mechanical contribution to lumbar stress injuries in female gymnasts.