In the

    United States Court of Appeals
                For the Seventh Circuit
                    ____________________
No. 19-2263
JUDY LYNN PRATER,
                                                Plaintiff-Appellant,
                                v.

ANDREW M. SAUL,
Commissioner of Social Security,
                                               Defendant-Appellee.
                    ____________________

        Appeal from the United States District Court for the
        Northern District of Indiana, Fort Wayne Division.
       No. 1:18-cv-00204-WCL-SLC — William C. Lee, Judge.
                    ____________________

  ARGUED DECEMBER 17, 2019 — DECIDED JANUARY 15, 2020
               ____________________

   Before RIPPLE, SYKES, and ST. EVE, Circuit Judges.
    PER CURIAM. Judy Prater applied for Social Security Dis-
ability Insurance Benefits based on a variety of mental and
physical impairments. An administrative law judge denied
her application on the ground that her residual functional
capacity (“RFC”) allows her to perform limited sedentary
work, and the district court affirmed. On appeal, Ms. Prater
argues only that the RFC assessment is too vague about her
2                                                  No. 19-2263

need to alternate between sitting and standing. However,
because the sit/stand limitation in the RFC assessment speci-
fies that Ms. Prater may change positions as needed so long
as she remains in position for at least thirty minutes at a
time, we affirm the judgment of the district court.
                               I.
                      BACKGROUND
                              A.
    Ms. Prater applied for benefits in 2015, alleging a disabil-
ity onset date in April of that year. At the time of the admin-
istrative law judge’s (“ALJ”) decision two years later,
Ms. Prater was a forty-seven-year-old woman who weighed
about 400 pounds and stood five feet, four inches tall, which
her doctor diagnosed as “morbid obesity.” A.R. at 672.
X-rays from 2015 showed that she suffered from mild to
moderate degenerative joint disease in her feet and knees
and mild to moderate degenerative disc disease in her spine.
She was also diabetic and had a history of gout, which she
treated with prescribed medication. On her application,
Ms. Prater stated that at her last job she experienced pain
and fatigue “all the time.” A.R. at 220. She reported these
symptoms to her doctors, but her examinations revealed
generally normal findings despite her many diagnoses.
None of her treating physicians offered an opinion that she
must alternate between sitting and standing with any par-
ticular frequency, or at all.
    As part of the benefits application process, several
state-agency physicians submitted reports about Ms. Prater’s
difficulties with standing or sitting for extended periods. She
reported to Dr. H. M. Bacchus that she could sit for thirty to
No. 19-2263                                                   3

sixty minutes and stand for twenty minutes, and
Dr. Bacchus concluded after an examination that Ms. Prater
“appear[ed] to have limitations in regard[] to prolonged
standing.” A.R. at 456. Based on a review of the medical rec-
ords, Dr. J. V. Corcoran opined that Ms. Prater could stand
for a total of two hours and sit for a total of six hours in an
eight-hour workday with normal breaks. Dr. Jerry Smartt
also reviewed the medical records and agreed with
Dr. Corcoran’s assessment.
                              B.
                               1.
   After her application was denied, Ms. Prater requested a
hearing before an ALJ. Ms. Prater testified that at her last job
working in a factory, after about an hour she would lose her
breath, and her feet, legs, and back would start to hurt. After
she stopped working, she experienced about the same level
of pain in her back and legs. The pain in her feet, however,
worsened. When she was on her feet for more than twen-
ty minutes, Ms. Prater said, the pain in all three areas would
increase. She testified that, because of the pain, she could ei-
ther stand or sit for only twenty minutes at a time.
    A vocational expert (“VE”) also testified at the hearing.
The ALJ asked the VE about the availability of work for a
hypothetical individual with the same vocational back-
ground, education, and age as Ms. Prater, who was limited
to sedentary work with various restrictions on lifting, carry-
ing, climbing, driving, and more. Further, this person could
“stand and walk no more than two hours of an eight-hour
day [and] remain seated for the rest of the day.” A.R. at 72.
The person also “would need to change positions in the
4                                                No. 19-2263

course of the day” but “could remain in place for at least
thirty minutes,” “whether it’s sitting or standing.” 

answered that such a person could not do any of
Ms. Prater’s past jobs but could perform other jobs that are
available in the national economy. It would not be “accepta-
ble in competitive employment,” however, for someone to
need to alternate positions after only twenty minutes.
A.R. at 75. Ms. Prater, who was represented by an attorney,
did not object to the ALJ’s questions or the VE’s responses,
nor did she ask the VE any questions.
    After considering all the evidence, the ALJ applied the
five-step analysis described in 20 C.F.R. § 404.1520 and con-
cluded that Ms. Prater was not disabled. The ALJ found that
Ms. Prater had multiple severe impairments, including de-
generative joint disease of the feet and knees, degenerative
disc disease of the spine, and obesity, but that none met or
equaled a listing for presumptive disability. Although she
could not perform any of her past jobs as a result of her im-
pairments, she had the residual functional capacity to per-
form sedentary work with numerous restrictions. Among
them, “she requires the ability to change positions as need-
ed, while remaining in each position at least 30 minutes.”
A.R. at 20. Ms. Prater’s impairments could be expected to
produce her described symptoms, the ALJ explained, but her
statements about their intensity, persistence, and limiting
effects were “not entirely consistent” with the evidence.
A.R. at 22. For example, the ALJ explained that, although
Ms. Prater was morbidly obese, “her physical examination
was otherwise unremarkable.” 

also noted that
Ms. Prater had experienced only “mild to moderate” degen-
erative changes in her feet, legs, and back. 

ALJ gave “significant weight” to the opinions of
No. 19-2263                                                  5

Dr. Corcoran and Dr. Smartt that Ms. Prater was capable of
performing sedentary work with occasional postural re-
strictions “because they are consistent with the record as a
whole.” 

Relying on the VE’s testimony, the ALJ
then concluded that Ms. Prater is not disabled because she is
capable of working as an address clerk, a document prepar-
er, or a surveillance monitor. Ms. Prater later asked the Ap-
peals Council to review the ALJ’s decision, but it denied her
request.
                              2.
    Ms. Prater filed this action in the district court in July
2018, seeking judicial review of the ALJ’s determination un-
der 42 U.S.C. § 405(g). She argued that the sit/stand limita-
tion in the RFC formulation was impermissibly vague. The
district court rejected Ms. Prater’s argument and ruled that
substantial evidence supported the ALJ’s decision.
                              II.
                       DISCUSSION
                              A.
    Because the Appeals Council denied Ms. Prater’s request
for review, the ALJ’s decision is the final decision of the
Commissioner of Social Security. See Burmester v. Berryhill,

, 509–10 (7th Cir. 2019). We will affirm a decision
on disability benefits if the ALJ applied the correct legal
standards in conformity with the agency’s rulings and regu-
lations and the conclusion is supported by substantial evi-
dence. 42 U.S.C. § 405(g); 

. “Sub-
stantial evidence” means “such relevant evidence as a rea-
sonable mind might accept as adequate to support a conclu-
6                                                   No. 19-2263

sion.” Biestek v. Berryhill, 

, 1154 (2019) (quota-
tion marks omitted) (citation omitted).
                               B.
    On appeal, Ms. Prater argues only that the sit/stand limi-
tation in the RFC finding is too vague to support the ALJ’s
conclusion that she can work. When a claimant’s impair-
ments require switching between positions during a work-
day, “[t]he RFC assessment must be specific as to the fre-
quency of the individual’s need to alternate sitting and
standing.” SSR 96-9p, 

, at *7 (July 2, 1996).
Ms. Prater contends that the ALJ was unclear about whether
she needs to be able to alternate between sitting and stand-
ing at will or whether she requires the option to switch posi-
tions only every thirty minutes.
    Ms. Prater strains to read into the RFC formulation am-
biguity that is not there. She primarily relies on Arnett v.
Astrue, 

, 593 (7th Cir. 2012), in which the ALJ
stated simply that the claimant needed to alternate between
sitting and standing “throughout the workday.” This re-
striction was too imprecise because it failed to “specify a
particular frequency, and [did] not require that Arnett be
able to choose to sit or stand when she feels it is necessary.”

Ms. Prater’s RFC assessment provides that
she must be permitted to alternate between sitting and
standing “as needed,” which, as Ms. Prater concedes, means
“at the will or control of the employee.” Appellant’s Br. 20.
Accordingly, the RFC assessment “pass[es] muster.” Id.;
see 

.
   Moreover, and contrary to Ms. Prater’s argument, layer-
ing a frequency limitation onto the “as needed” posi-
No. 19-2263                                                     7

tion-change requirement does not make the “hybrid” re-
striction ambiguous. As the ALJ’s colloquy with the VE illus-
trates, the thirty-minute constraint conveys that the claimant
will not be off-task too frequently throughout the day to pre-
clude competitive employment. See Ketelboeter v. Astrue,

, 626 (7th Cir. 2008); Schmidt v. Astrue, 

, 845 (7th Cir. 2007). Essentially, it places an outer limit on
Ms. Prater’s need to change positions and expresses her abil-
ity to do work-related activities on a sustained basis despite
her impairments. See SSR 96-8p, 

, at *1 (July
2, 1996). The time limit does not introduce ambiguity. There-
fore, the ALJ permissibly relied on the VE’s testimony that
someone who must alternate positions at will, but not more
than every thirty minutes, can maintain employment.
See Krell v. Saul, 

, 584 (7th Cir. 2019).
    Critically, Ms. Prater does not argue that the ALJ’s find-
ing that she could both sit and stand for thirty minutes at a
time lacks medical support, or that the ALJ improperly dis-
credited her testimony that she could remain in each posi-
tion for only twenty minutes. Nor does she assert—let alone
cite evidence to show—that she requires a more restrictive
RFC formulation. See Jozefyk v. Berryhill, 

, 498
(7th Cir. 2019). Because the RFC assessment adequately spec-
ified Ms. Prater’s sit/stand limitations, her one argument on
appeal fails.
                          Conclusion
   We conclude that the ALJ’s RFC formulation is not vague
and that the decision is supported by substantial evidence.
Therefore, we affirm the judgment of the district court.
                                                     AFFIRMED