MEMORANDUM & ORDER
John W. Lungstrum United States District Judge
Plaintiff Regina Ogle brings this action pursuant to 42 U.S.C. § 405(g) seeking judicial review of the decision of defendant, the Commissioner of Social Security, to deny her applications for social security disability insurance benefits under Title II of the Social Security Act and supplemental security income benefits under Title XVI of the Act According to plaintiff, the ALJ erred at step three when she concluded that plaintiff did not demonstrate an inability to ambulate effectively for purposes of Listing 1.02 and erred when she improperly discredited plaintiff’s testimony regarding her inability to ambulate effectively. Finding error as alleged by plaintiff in the ALJ’s step three evaluation, the court orders that the Commissioner’s decision is reversed and that judgment be entered in accordance with the fourth sentence of 42 U.S.C. § 405(g) remanding this case for further proceedings consistent with this opinion.
I. Procedural Background
On July 21, 2010, plaintiff protectively filed an application for disability insurance benefits and for supplemental security income benefits, alleging disability beginning December 31, 2009. The applications were denied both initially and upon reconsideration. At plaintiff’s request, an administrative law judge (“ALJ”) held a hearing on February 9, 2012, at which both plaintiff and her attorney were present. On March 9, 2012, the ALJ rendered a decision in which she determined that plaintiff was not under a “disability” as defined by the Social Security Act from December 31, 2009 through the date of the decision. Consequently, the ALJ denied all benefits to plaintiff. After the ALJ’s unfavorable decision, plaintiff requested review by the Appeals Council. The Appeals Council denied plaintiff’s request for review, rendering the ALJ’s decision the final decision of defendant.
II. Standard of Review
Judicial review under 42 U.S.C. § 405(g) is limited to whether defendant’s decision is supported by substantial evidence in the record as a whole and whether defendant applied the correct legal standards. See Wells v. Colvin, 727 F.3d 1061, 1067 (10th Cir. 2013) (citing Wilson v. Astrue, 602 F.3d 1136, 1140 (10th Cir. 2010)). The Tenth Circuit has defined “substantial evidence” as “such relevant evidence as a reasonable mind might accept as adequate to support a conclusion.” Id. (quoting Wilson, 602 F.3d at 1140). In the course of its review, the court may not reweigh the evidence or substitute its judgment for that of defendant. Cowan v. Astrue, 552 F.3d 1182, 1185 (10th Cir. 2008).
III. Relevant Framework for Analyzing Claim of Disability and the ALJ’s Findings
A “disability” for purposes of the Social Security Act requires both the “inability to engage in any substantial gainful activity” and “a medically determinable physical or mental impairment which can be expected to result in death or which has lasted or can be expected to last for a continuous period of not less than 12 months.” Bussell v. Astrue, 463 Fed.Appx. 779, 781 (10th Cir. 2012) (quoting 42 U.S.C. § 423(d)(1)(A)). The Social Security Act further provides that an individual “shall be determined to be under a disability only if his physical or mental impairment or impairments are of such severity that he is not only unable to do his previous work but cannot, considering his age, education, and work experience, engage in any other kind of substantial gainful work which exists in the national economy.” Wilson, 602 F.3d at 1140 (quoting Barnhart v. Thomas, 540 U.S. 20, 21-22 (2003) (quoting 42 U.S.C. § 423(d)(2)(A), 1382c(a)(3)(B))).
The Social Security Administration has established a five-step sequential evaluation process for determining whether a claimant is disabled, see id. at 1139, and the ALJ in this case followed the five-step process. If a determination can be made at any of the steps that a claimant is or is not disabled, evaluation under a subsequent step is not necessary. Id. Step one requires the claimant to show that he or she is not presently engaged in substantial gainful activity. Id. Here, the ALJ determined that plaintiff was not engaged in substantial gainful activity and, thus, properly proceeded to the second step. The second step of the evaluation process involves a determination of whether “the claimant has a medically severe impairment or combination of impairments” that significantly limits his or her ability to perform basic work activities. Wall v. Astrue, 561 F.3d 1048, 1052 (10th Cir. 2009) (citing 20 C.F.R. § 404.1521). At this step, the ALJ concluded that plaintiff had several severe impairments, including asthma, panic disorder, depressive disorder, lumbar spondylosis, obesity, possible tarsal coalition, ankle valgus, bilateral osteoarthritis and patellar femoral dysfunction. The ALJ identified plaintiff’s migraine headaches and hypertension as non-severe impairments. Thus, the ALJ proceeded to step three.
In step three, the ALJ determines whether the impairment “is equivalent to one of a number of listed impairments that the Commissioner acknowledges are so severe as to preclude substantial gainful activity.” Best-Willie v. Colvin, 514 Fed.Appx. 728, 733 (10th Cir. 2013). “If the impairment is listed and thus conclusively presumed to be disabling, the claimant is entitled to benefits.” Id. If not, the evaluation proceeds to the fourth step, where the claimant must show that the “impairment or combination of impairments prevents him from performing his [or her] past work.” Wilson, 602 F.3d at 1139 (quoting Lax v. Astrue, 489 F.3d 1080, 1084 (10th Cir. 2007)). With respect to the third step of the process in this case, the ALJ determined that plaintiff’s impairments were not listed or medically equivalent to those listed in the relevant regulations. Here, the ALJ specifically rejected plaintiff’s argument that she met Listing 1.02 due to her inability to ambulate effectively. According to the ALJ, plaintiff’s ability to ambulate with the use of a single cane, as opposed to a walker that requires the use of both hands, necessarily meant that she failed to meet the Listing.
At the fourth step, the ALJ determined that plaintiff retained the residual functional capacity (RFC) to perform a hybrid of light and sedentary work as defined in 20 C.F.R. §§ 404.1567 and 416.967. Among other capabilities, the ALJ concluded that plaintiff could sit for 6 hours in an 8-hour workday and stand or walk for at least 2 hours in an 8-hour workday. The ALJ concluded that plaintiff would need the ability to alternate between sitting and standing at least every 30 minutes and would require a job that could be performed while using a handheld assistive device, which was required for prolonged ambulation and standing. The ALJ concluded, however, that plaintiff could stand for at least 30 minutes without the need for an assistive device. Based on evidence adduced from the vocational expert, the ALJ concluded that plaintiff, with the limitations established in plaintiff’s RFC, could not perform her past relevant work as a cook or certified nurse’s aide as the demands of those jobs would exceed plaintiff’s residual functional capacity.
Thus, the ALJ proceeded to the fifth and final step of the sequential evaluation process– determining whether the claimant has the residual functional capacity “to perform work in the national economy, given her age, education, and work experience.” See id. (quoting Lax, 489 F.3d at 1084). At that point, the ALJ properly shifted the burden of proof to defendant to establish that plaintiff retains a sufficient capacity to perform an alternative work activity and that there are sufficient jobs in the national economy for a hypothetical person with the claimant’s impairments. Raymond v. Astrue, 621 F.3d 1269, 1274 (10th Cir. 2009). At this step, the ALJ concluded that plaintiff was not disabled, a conclusion that rested on a finding that plaintiff, despite her limitations, nonetheless could perform jobs that exist in significant numbers in the national economy, such as a Semiconductor Bonder, Lens Inserter and Stringer Machine Tender.
IV. The ALJ’s Step Three Evaluation
In her motion, plaintiff contends that the ALJ erred at step three when she concluded that plaintiff did not demonstrate an inability to ambulate effectively for purposes of Listing 1.02.At step three of her evaluation, the ALJ determined that plaintiff failed to meet Listing 1.02 because plaintiff failed to meet her burden to establish an inability to ambulate effectively. It is undisputed that an “inability to ambulate ...