Appeal from the Circuit Court of Lake County. No. 03--MR-716. Honorable Raymond J. McKoski, Judge, Presiding.
 The opinion of the court was delivered by: Justice Kapala
 Plaintiff, Scott Alm, appeals from an order of the circuit court of Lake County affirming the decision of defendant, the Lincolnshire Police Pension Board (Board), denying plaintiff's application for line-of-duty disability benefits, and instead awarding him nonduty benefits. Plaintiff contends that the Board's decision is against the manifest weight of the evidence. We reverse.
 On June 17, 2000, plaintiff was employed by the Village of Lincolnshire as a sworn police officer and was assigned to the police department's bicycle patrol unit. Plaintiff's shift was from 11 p.m. to 6:30 a.m. At the hearing on his application, plaintiff testified that his job on the date in question "was to do premise checks, check buildings in our industrial park, patrol the parking lots of businesses that are open, the downtown area, and then later on in the night head over to the residential area." The assignment involved riding on a variety of terrain--up on curbs, through grass, and behind buildings. Additionally, plaintiff carried approximately 20 pounds of gear on his person and another 5 to10 pounds in a police bag attached to the back of the bicycle. As a member of the bicycle patrol unit, plaintiff had performed such duties as making drug arrests, conducting traffic stops, and issuing both parking tickets and tickets for moving violations. Plaintiff also testified that during bike patrol training he was taught to stay on his bicycle as much as possible because the bicycle gave him a mechanical advantage over people on foot.
 At about 2 a.m. on June 17, 2000, while pedaling his bicycle, plaintiff experienced significant pain in his right knee and noticed swelling. He had not fallen or had any other sort of accident. Plaintiff immediately sought treatment and was ultimately diagnosed as suffering from, inter alia, a tear in the medial meniscus of his right knee. Plaintiff underwent several surgical procedures, but his condition restricted his ability to perform various physical activities, such as running, kneeling, and crawling. Plaintiff had no prior history of knee problems.
 At the Board's request, plaintiff was examined by two physicians, Dr. David M. Zoellick and Dr. Robert D. McMillan, whose reports were admitted into evidence, along with the reports of other physicians who treated or examined plaintiff. Dr. Zoellick indicated in his report that it was his impression that plaintiff was injured at work in June 2000. Dr. McMillan's report states, in pertinent part, as follows:
 "As to the proximal [sic] proximate cause for the disability, it is unclear to me whether there was any discreet [sic] injury or whether this was a cumulative stress injury that may have occurred relating to his police work. [Plaintiff] denies significant athletic activity prior to the onset of his disability, and it seems that it was timed to his work, and was well documented as such as outlined in the letter from [plaintiff's attorney].
 My speculation as to the evolution of [plaintiff's] problem is that he started with a torn cartilage that failed to improve probably because of the mild varus alignment (bowleg) that he has naturally. This puts more weight on the inner aspect of the knee."
 Dr. McMillan also observed that records from plaintiff's third and fourth operations indicated the presence of an abnormality that had not been mentioned in earlier medical records. Dr. McMillan noted in his report:
 "Not having seen initial MRIs or x-rays, I cannot date this abnormality, but it does point to the possibility existing of a pre-existing condition, were this present on his initial work up. This may have contributed to the likelihood of abnormality evolving with his police work.
 Nonetheless, it is clear that this man had an active and full physical life prior to the immediate onset of his symptoms and as such, it seems that the police activity certainly was the proximate cause for his abnormality."
 In its written decision, the Board found that plaintiff was disabled, but that he had not been injured in the performance of an act of duty. The Board concluded that the manner in which plaintiff was pedaling his bicycle when his knee began to hurt did not involve any special risk not shared by civilians. The Board also noted Dr. McMillan's view that plaintiff's condition evolved from a torn cartilage that failed to improve because of plaintiff's mild varus alignment. Accordingly, the Board awarded plaintiff nonduty benefits. The trial court affirmed the Board's decision, and this appeal followed.
 The findings and conclusions of an administrative agency on questions of fact are deemed prima facie true and correct and will not be disturbed on review unless they are against the manifest weight of the evidence, meaning that the opposite conclusion is clearly evident. Trettenero v. Police Pension Fund, 333 Ill. App. 3d 792, 801 (2002). We review the decision of the agency, not the judgment of the trial court. Du Page County Board of Review v. Department of Revenue, 339 Ill. App. 3d 230, 235 (2003). Determinations regarding questions of law are reviewed de novo. White v. City of Aurora, 323 Ill. App. 3d 733, 735 (2001). In White, because the facts were uncontroverted and the Board of Trustees of the City of Aurora was charged only with interpreting the meaning of the term "act of duty" found in section 3--114.1 of the Illinois Pension Code (Code) (40 ILCS 5/3--114.1 (West 1998)), we decided that case under a de novo standard of review. White, 323 Ill. App. 3d at 735. Likewise, in the instant case, the facts are undisputed and the only issue before the Board was the meaning of "act of duty." Accordingly, under White, we review the Board's decision de novo.
 At the time plaintiff became disabled, section 3--114.1 of the Code provided, in pertinent part:
 "If a police officer as the result of sickness, accident or injury incurred in or resulting from the performance of an act of duty, is found to be physically or mentally disabled for service in the police department, so as to render necessary his or her suspension or retirement from the police service, the police officer shall be entitled to a disability retirement pension of 65% of the salary attached to the rank on the police force held by the officer at the date of suspension of duty or retirement. A police officer shall be considered 'on duty', while on any assignment approved by the chief ...