OPINION
ANDERSON, G. BARRY, Justice.The issue presented in this case is whether respondent Karl L. Anderson is barred from receiving workers’ compensation benefits because he failed to give timely notice to his employer of a work-related injury. A compensation judge found that Anderson was barred from receiving workers’ compensation benefits because his written notice of injury, given nearly 2 years after Anderson’s last day of work, was not timely and Anderson’s employer, Frontier Communications, did not have actual knowledge that Anderson’s back problems were work-related. The Workers’ Compensation Court of Appeals reversed, concluding that a reasonable person in Anderson’s position would not have known that his injury was compensable until Anderson’s doctors provided written reports to Anderson’s attorney establishing a relationship between Anderson’s back problems and his job duties. We reverse.
From 1987 to 2007 Anderson worked for Frontier Communications as a lineman. Anderson’s job entailed installing cable, repairing and replacing cable boxes, and maintaining and stringing overhead cable — a very physical job that required Anderson to lift as much as 100 pounds at a time. According to Anderson, the most strenuous part of his job was bending over to mark underground cables with small flags to guard against accidental damage *145to the cables from digging. Anderson testified that he went through 7,000 to 10,000 flags in a season.
Anderson had no back problems before joining Frontier in 1987. In 1996, Anderson asked his physician for a shot of Demerol, claiming his back hurt after a day of shoveling dirt at work. Anderson testified before the compensation judge that although he initially reported this to his physician as a work injury, he changed his mind after realizing that it would result in a workers’ compensation claim. In 1998, Anderson hurt his low back getting out of his employer’s truck, but again did not report this as a work injury.
Between 2004 and 2005, Anderson’s back progressively worsened, with pain at the beltline and down his right leg. The pain was worse at the end of a work day and progressively worse during the work week. According to Anderson, nearly anything he did seemed to increase his back pain and he gave up playing sports. Anderson did not initially seek medical treatment, figuring he was just getting old. By March 2007 Anderson was icing his back nightly. Anderson saw his physician for the problem; x-rays showed degenerative changes in Anderson’s low back and wrist. He was referred for cortisone shots, which provided no relief; Anderson was then referred to a spinal surgeon. Anderson agreed that by April 2007 he knew that the work activities that he was doing at Frontier Communications were aggravating his low back.
In May 2007 the surgeon diagnosed Anderson with spondylolisthesis, spinal stenosis, and degenerative disc disease. Anderson’s medical records reflect that Anderson’s job was discussed at the initial consultation. In testimony before the compensation judge, Anderson further agreed that after talking with the surgeon in May 2007, he knew that the work activities were a cause of his low back problems or were aggravating his low back problems. Indeed, Anderson testified:
[Ajfter I saw the first x-rays and the MRI’s and the results and how much damage was done to my back, and they explained that everytime I bent over that there was two and a half centimeters of travel in my spinal cord, I mean in my back, and that it was pinching my spinal cord, that’s when I realized from all the stooping and' bending that I’d been doing all these years that my discs were wore out and they had to be replaced.
But Anderson’s surgeon did not place any restrictions on Anderson’s work during the time period between the surgical consultation and the surgery itself.
Anderson told his supervisor at Frontier Communications in June 2007 that he needed to take time off for low-back surgery, but did not tell anyone at Frontier that his back condition related to his work. Anderson’s last day of work was July 4, 2007. In testimony before the compensation judge, Anderson agreed that he knew by July 4th of 2007 that his low back was aggravated by his work activities at Frontier Communications. On July 6, 2007, the surgeon performed an anterior discectomy and fusion. Anderson had additional surgery a week later for compression of the nerve root and again in February 2008 to redo part of the spinal fusion. Despite the surgeries, Anderson continues to have pain in his left leg and hip. He has trouble standing, sitting, and walking for more than a few minutes, and has not worked since July 4, 2007.
Anderson received short-term disability benefits for 90 days through his union and long-term disability benefits after 90 days. The long-term disability policy required Anderson to apply for social security disability insurance (SSDI) benefits, which *146were initially denied. In March 2009 the Social Security Administration found Anderson disabled as of July 4, 2007, his last day of work, and awarded Anderson benefits retroactive to January 2008. Anderson received a lump-sum SSDI payment, from which the long-term disability insurer demanded reimbursement for benefits paid under the long-term disability policy. Anderson consulted an attorney for help with the insurer’s demand and eventually repaid the long-term disability insurer.
In April 2009 Anderson’s attorney wrote to his physicians, asking whether the long-term physical demands of Anderson’s job were a contributing factor to Anderson’s need for surgery and medical treatment. Anderson’s family doctor and his surgeon each responded that the physical demands of Anderson’s job had significantly aggravated Anderson’s pre-existing back condition. In May 2009, nearly two years after Anderson’s last day of work, Anderson’s attorney gave Frontier written notice that Anderson was claiming his back injury was work-related.
For an employee to receive workers’ compensation benefits, and subject to several exceptions not applicable here, Minn. Stat. § 176.141 (2010) requires either that the employee give written notice of injury to the employer, or that the employer have actual knowledge of the injury, within 180 days of the occurrence of the injury. Nevertheless, we have held that the notice period under section 176.141 may be tolled until “it becomes reasonably apparent to the employee that the injury has resulted in, or is likely to cause, a compensable disability.” Issacson v. Minnetonka, Inc., 411 N.W.2d 865, 867 (Minn.1987). Put another way, “[t]he time period for notice or claim does not begin to run until the claimant, as a reasonable person, should recognize the nature, seriousness and probable compensable character of his injury or disease.” Id. (quoting 3 A. Larson, The Law of Workmen’s Compensation § 78.41(a) (1983));1 cf. Jones v. Thermo King, 461 N.W.2d 915, 917 (Minn.1990) (observing “that for both personal injury and occupational disease, the statute of limitations begins to run when the employee has sufficient information of the nature of the injury or disease, its seriousness, and probable compensability”).
A compensation judge found that Anderson had sustained a Gillette-type injury arising out of and in the course of his employment, culminating on Anderson’s last day of work. See Gillette v. Harold, Inc., 257 Minn. 313, 320-22, 101 N.W.2d 200, 205-06 (1960) (holding that when a preexisting infirmity is aggravated by repetitive minute trauma as a result of the ordinary and necessary duties of employment, the disability resulting from such aggravation is compensable as a personal injury under the workers’ compensation statute). The compensation judge found, as Anderson had testified, that Anderson knew in April 2007 “that his work aggravated his low back.” The compensation judge further found that Anderson, after talking to the surgeon, “knew the work aggravated or caused the low back problem.” Although Anderson did not recall talking to either of his doctors “about work causing or aggravating his problem,” the compensation judge found that Anderson “assumed that it did” and that from April 2007 on, Anderson “assumed ... that the work caused or aggravated his problem.” Based on a preponderance of the evidence, the compensation judge found that *147Anderson had not given his employer timely notice of his claimed work injury. The compensation judge further found that Anderson had not established that his employer had “inquiry notice” of Anderson’s injury as of July 4, 2007, Anderson’s last day of work.2 The compensation judge therefore denied Anderson’s claim for workers’ compensation benefits.
The Workers’ Compensation Court of Appeals (WCCA) reversed the denial of benefits. Anderson v. Frontier Commc’ns, 2011 WL 1789771 (Minn. WCCA Apr. 11, 2011). The WCCA noted that the medical records of Anderson’s initial visit to his family physician in March 2007 made no mention of Anderson’s work. Id. at *2. The WCCA further noted that Anderson’s surgeon placed no restrictions on Anderson, and Anderson continued to work until just a couple of days before his back surgery. Id. The WCCA points out that when Anderson returned to his surgeon in January 2008 complaining of continuing low-back problems, he also reported numbness in his left hand, and a cervical MRI performed in February 2008 showed mild canal stenosis. Id. According to the WCCA, Anderson’s family doctor attributed Anderson’s back and wrist problems in March 2007 to “degenerative changes.” Id. at ⅜4. The WCCA reasoned that Anderson should not have been required to give notice to his employer that his back problems were work-related “when there was no medical evidence making that connection and where the existing medical evidence provided a different reason for his problems.” Id. at *5. According to the WCCA, “substantial evidence does not support a conclusion that a ‘reasonable’ person [in Anderson’s position] would have known he had a compensable injury which needed to be reported to his employer until [Anderson’s doctors] provided reports establishing a work relationship to Mr. Anderson’s attorney.” Id. The employer and its insurer petitioned for review by certiorari.
I.
Under Minn.Stat. § 176.141 and our case law, an employee must give notice of injury no more than 180 days after “it becomes reasonably apparent to the employee that the injury has resulted in, or is likely to cause, a compensable disability.” See Issacson v. Minnetonka, Inc., 411 N.W.2d 865, 867 (Minn.1987). We first consider whether the WCCA erred in overturning the compensation judge’s finding that Anderson failed to give timely notice to Frontier of his work-related injury.
The date on which an employee has sufficient knowledge to trigger the duty to give notice of injury is a question of fact. Barcel v. Barrel Finish, 304 Minn. 536, 538, 232 N.W.2d 13, 15 (1975) (citing Balow v. Kellogg Coop. Creamery Ass’n, 248 Minn. 20, 78 N.W.2d 430 (1956)). The WCCA must affirm the compensation judge’s findings of fact unless they are “clearly erroneous and unsupported by substantial evidence in view of the entire record as submitted.” Minn.Stat. § 176.421, subd. 1(3) (2010). Moreover, when the evidence conflicts or when more than one inference may reasonably be drawn from the evidence, the compensation judge’s findings are to be affirmed. *148Hengemuhle v. Long Prairie Jaycees, 358 N.W.2d 54, 60 (Minn.1984). “When a workers’ compensation matter comes to this court on certiorari, if the compensation judge’s findings have been reversed, we look at the record to see if the compensation judge’s findings had substantial evidentiary support.” Freyholtz v. Blackduck Sch. Dist. No. 32, 613 N.W.2d 757, 758 (Minn.2000). We review questions of law de novo. Roemhildt v. Gresser Cos., 729 N.W.2d 289, 292 (Minn.2007).
We conclude that there was substantial evidentiary support for the compensation judge’s finding that Anderson knew no later than July 2007 that he had a compen-sable work-related injury. Anderson testified that his doctors explained to him before the surgery that every time he bent over to mark an underground line — which Anderson testified he did 7,000 to 10,000 times a year — his vertebrae pinched his spinal cord, eventually wearing out the discs in his back. According to Anderson,
[AJfter I saw the first x-rays and the MRI’s and the results and how much damage was done to my back, and they explained that everytime I bent over that there was two and a half centimeters of travel in my spinal cord, I mean in my back, and that it was pinching my spinal cord, that’s when I realized from all the stooping and bending that I’d been doing all these years that my discs were wore out and they had to be replaced.
The WCCA agreed with the employer that “a medical report establishing a Gillette injury is not required before notice must be given.” Anderson v. Frontier Commc’ns, 2011 WL 1739771, at *4 (Minn. WCCA Apr. 11, 2011). Rather, the WCCA concluded, “[t]he question here is whether Mr. Anderson’s actions were reasonable given the information available to him.” Id. Nevertheless, the WCCA reversed the compensation judge on the ground that Anderson “should not have been required to give notice to his employer that his problems were the result of his work history when there was no medical evidence making that connection and where the existing medical evidence provided a different reason for his problems.” Id. at *5.
In concluding that there was “no medical evidence” connecting Anderson’s back problems to his work, the WCCA and the dissent appear to rely on the absence of any specific conclusion to that effect in Anderson’s written medical records. But Anderson’s medical records reflect that the nature of Anderson’s job was discussed at the initial surgical consultation:
The patient works for a telecommunications company and does a lot of physical labor including working up and down the telephone poles installing equipment. He sometimes lifts 50-60 pounds of weight. He is presently still working full time.
And Anderson himself testified that before the surgery his doctors “explained that everytime [he] bent over that there was two and a half centimeters of travel in ... [his] back, and that it was pinching [his] spinal cord.” Anderson further testified that seeing the x-rays and MRI’s before the surgery, he “realized from all the stooping and bending that [he’d] been doing all these years that [his] discs were wore out and they had to be replaced.” Under our standard from Issacson, “the information available to” Anderson— whether or not documented in Anderson’s medical records — was that the wear and tear on his discs was the result of his work activities.
The dissent dismisses Anderson’s testimony because it was in response to “questions posed to Anderson ... phrased by Anderson’s employer using a disjunctive clause” — that is, whether Anderson’s work *149for Frontier Communications was “causing” or “aggravating” Anderson’s back problems. According to the dissent, “the fact that [Anderson] acknowledged that work may have aggravated his back pain does not mean that he also acknowledged that work caused his back injury.” But Anderson’s injuries were compensable, whether caused in the first instance by his work or whether his work merely aggravated a preexisting condition. See Gillette v. Harold Inc., 257 Minn. 313, 317, 101 N.W.2d 200, 204 (1960) (recognizing “that a preexisting disease or infirmity of the employee does not disqualify a claim arising out of employment if the employment aggravated, accelerated, or combined with the disease or infirmity to produce disability for which compensation is sought”).
The WCCA further concluded that the compensation judge’s finding should be reversed because “the existing medical evidence provided a different reason for [Anderson’s] problems.” Anderson, 2011 WL 1739771, at *5. That “different reason,” in the WCCA’s view, appears to be “degenerative changes.” See id. at *4 (“Dr. Gallagher attributed the hand problems and the low back problem to degenerative changes.”). The WCCA analogized Anderson’s case to Beckmann v. Quebecor Printing, Inc., 1997 WL 347877 (Minn. WCCA June 9, 1997). Anderson, 2011 WL 1739771, at *4. Beckmann is distinguishable on its facts. In Beckmann, the employee’s medical records initially attributed his hip pain to a prostate problem — a condition inherently inconsistent with a work-related injury; even after a total hip replacement, Beckmann’s doctor denied that his condition was due to his employment. 1997 WL 347877, at *4. In other words, in Beckmann there was a specific, competing, non-work-related explanation for the employee’s injuries. In this case, a diagnosis of “degenerative changes” is not inherently inconsistent with a work-related injury, given the nature of Anderson’s job duties and the length of time those duties were performed.
When the evidence conflicts or when more than one inference may reasonably be drawn from the evidence, the compensation judge’s findings are to be affirmed. Hengemuhle, 358 N.W.2d at 60. Because there was substantial evidence, in the form of Anderson’s own testimony, to support the compensation judge’s finding that Anderson should have realized the seriousness of his condition and that the work he did caused or aggravated his back problems, we reverse the WCCA and affirm the compensation judge’s finding that Anderson’s notice of injury in May 2009 was not timely.
II.
Under Minn.Stat. § 176.141, Anderson may still recover workers’ compensation benefits, despite his failure to give timely notice of his injury, if his employer had actual knowledge of his injury. The compensation judge found that Anderson had not established that Frontier had notice of his injury as of his last day of work. Because of its disposition of the case, the WCCA did not reach the question of Frontier Communication’s knowledge. Although we could remand the matter to the WCCA for its consideration, neither Anderson or Frontier disputed the compensation judge’s factual findings with respect to the employer’s knowledge. Rather, Anderson argued to the WCCA that the compensation judge erred, as a matter of law, in concluding that Frontier did not have timely inquiry notice of Anderson’s injury. In the interest of judicial economy, we will address the issue.
We have defined “actual knowledge” in workers’ compensation cases as follows:
*150“Actual knowledge” is knowledge of such information as would put a reasonable man on inquiry. Mere knowledge of disability following a traumatic injury is not sufficient, for the facts and circumstances of either the disability or the injury must be such as would put a reasonable man on inquiry that the disability is work-related.
Pojanowski v. Hart, 288 Minn. 77, 81, 178 N.W.2d 913, 916 (1970) (citations omitted). As we observed in Issacson, “[i]t is simply not enough that the employer is aware that an employee has shoulder pain.” Issacson v. Minnetonka, Inc., 411 N.W.2d 865, 867 (Minn.1987). Rather, to constitute actual knowledge, “an employer must have some information connecting work activity with an injury.” Id.
The compensation judge found that Anderson did not tell anyone at work that his back condition related to the demands of his job. Anderson does not dispute this finding. Rather, Anderson argued to the WCCA that because Frontier knew the demands of Anderson’s job, Frontier had sufficient information in May 2007, when Anderson told his supervisor that he needed to take time off for back surgery, to inquire whether Anderson’s job was a substantial contributing factor in Anderson’s injury. But an employer cannot be deemed to have actual knowledge of an injury before the injury occurs. Dickson v. Minn. Vikings Football Club, 2008 WL 4790296, at *10 (Minn. WCCA Sept. 9, 2008). In this case, the compensation judge found that Anderson’s injury culminated on July 4, 2007, his last day of work, a finding that neither Anderson nor Frontier have challenged on appeal. We conclude that the record is sufficient to support the compensation judge’s findings relating to the employee’s knowledge.
Because we affirm the compensation judge’s findings that Anderson did not timely provide notice to his employer that he sustained a work-related injury and the employer did not have actual knowledge of such an injury, we reverse the WCCA and affirm the compensation judge’s denial of benefits.
Reversed.
. This section is currently located in 7 Arthur Larson & Lex K. Larson, Larson's Workers' Compensation Law § 126.05[ 1] (2011).
. “Actual knowledge" is knowledge of such information as would put a reasonable man on inquiry. Mere knowledge of disability following a traumatic injury is not sufficient, for the facts and circumstances of either the disability or the injury must be such as would put a reasonable man on inquiry that the disability is work-related.
Pojanowski v. Hart, 288 Minn. 77, 81, 178 N.W.2d 913, 916 (1970) (citations omitted).