Yeah, if you ascribe to the theory that pain is telling you to avoid something then than makes sense. In surgery we are told to give spirometers to all post op patients to prevent alveolar collapse ( air sacs) and resultant pneumonia. Psrt of rounding with the attending was the inevitable question " Are ya usin yur spirometer honey, lemme see" " Aw, thats great honey , just great".
Total garbage. A brief synopsis...

Incentive spirometers are often used as part of pulmonary supportive care in hospitalized
patients. The use of the device encourages deep inspiration, which is to aid in use of maximal
lung volume in setting of pain and immobility. This is desired to prevent as well as hasten
reversal of atelectasis.
The data on incentive spirometry’s efficacy is limited to post operative patients. The two
surgical groups studied the most have been patients undergoing upper abdominal surgery and
CABG. Cochrane review of the upper abdominal surgery studies show that there is no
demonstrable benefit of incentive spirometry. This meta analysis reviewed 11 studies that were
all prospective, but over half did not have clear methods of randomization, and masking was
also not clearly part of study design. In general, the studies included were designed to evaluate
the efficacy of incentive spirometry or deep breathing exercises in preventing post operative
pulmonary complications and restoring/preserving lung function.
The second group of patients in which incentive spirometry has been studied is patients who
have had CABG. In this population, there is also a Cochrane review, and the meta analysis
included four RCTs, which showed again, a lack of demonstrable benefit with use of the
incentive spirometer. However, in this meta analysis, the authors comment that there is need
for a better designed study with more statistical power and thus at least in post-CABG patients,
one cannot decisively conclude that incentive spirometry is of no benefit. The outcomes were
similar to those in the upper abdominal surgery patients, e.g. assessing atelectasis (either by
chest radiograph or CT scan), post operative pulmonary complications (like pneumonia),
pulmonary function, and duration of hospitalization.