This is a workers' compensation case. the Commission reversed the ALJ's finding that 51-year-old X sustained a compensable aggravation of a pre-existing condition which caused internal damage to her artificial hip. Appellant argues that the Commission's finding is not supported by substantial evidence. We disagree and affirm. On March 12, 1997, while working as a dental assistant for appellee, Dr. Hestir, appellant had gotten down on her hands and knees to clean grease from the floor at her employer's request. As she got up from the floor, she experienced a sharp pain and advised her employer that she had hurt herself. However, she continued to work the rest of that day and worked the following day as well. She first sought medical treatment on March 18, 1997, and continued to work on crutches. She was taken off work by her doctor on April 14, 1997. on December 10, 1997, she underwent hip revision surgery where it was discovered that she had a cracked or scratched femoral head. Appellant testified that she had the original hip replacement surgery in January of 1995 as a result of an automobile accident twenty years earlier. She had no pain from this surgery other than around the incision. She testified that virtually everyone in the office that day saw her down on her hands and knees scrubbing the floor. Appellant was sure she told the girls in the office that she had hurt her hip. She stated that it was hard for her to walk around after she got up from the floor. Several of appellant's co-workers testified that appellant did not seem to be in any pain after getting up from the floor and that appellant had complained of hip pain prior to the incident on March 12, 1997. According to his deposition testimony, Dr. Lowry Barnes stated that, when someone suffers a dislocation, the person immediately knows it. Although he agreed that it did not take much to dislocate an artificial hip, he was without an opinion as to whether appellant's work-related incident resulted in the need for her medical treatment. Dr. Randall Hestir, appellant's employer, described appellant as an excellent worker who rarely complained of pain. He stated in his deposition that, although he did not remember appellant saying that she had hurt her hip that day, she did inform him the next day or the following day. Dr. Tad Pruitt stated in his deposition that simply getting up from the floor should not have cracked a femoral head. He also testified that he would expect someone in that condition to experience a significant amount of pain and difficulty walking. When the issue is whether the Commission's findings are supported by substantial evidence, we view the evidence in the light most favorable to the findings of the Commission and give the testimony its strongest probative force in favor of the Commission's actions. Tyson Foods, Inc. v. Disheroon, 26 Ark. App. 145, 761 S.W.2d 617 (1988). Substantial evidence is such relevant evidence as a reasonable mind might accept as adequate to support a conclusion. Carroll Gen. Hosp. v. Green, 54 Ark. App. 102, 923 S.W.2d 878 (1996). We do not reverse a decision of the Commission unless we are convinced that fair-minded persons with the same facts before them could not have arrived at the conclusion reached by the Commission. Willmon v. Allen Canning Co., 38 Ark. App. 105, 828 S.W.2d 868 (1992). Furthermore, it is the function of the Commission to determine the credibility of the witnesses and the weight to be given their testimony. Whaley v. Hardee's, 51 Ark. App. 166, 912 S.W.2d 14 (1995). In reversing the ALJ's decision, the Commission noted that Dr. Hestir, appellant's employer, could not confirm that appellant had immediately reported an injury to him. In fact, appellant continued to work and did not seek medical treatment until nearly a week later. The Commission noted that Dr. Barnes stated that a person would immediately know they had dislocated a hip and that Dr. Pruitt stated that the pain would be significant. The Commission found that appellant's testimony regarding the pain she suffered was entitled to little weight and, instead, relied on the testimony of her co-workers who had failed to notice anything the matter with appellant after she got up from the floor and who had heard appellant complain of hip pain prior to the incident. We conclude that the Commission's decision is supported by substantial evidence.