Background and Objectives: The aim of this study is to objectively evaluate the effects of a six-week intermittent hypoxic–hyperoxic exposure program on blood pressure, respiratory function, cardiac autonomic nervous activity and C Reactive Protein levels in older adults. Materials and Methods: A double-blinded randomized controlled clinical trial was conducted on twenty-two older adults. Heart rate variability, respiratory function, blood pressure, C Reactive Protein levels and oxygen saturation were measured at two time points: baseline and after 6 weeks of treatment. Results: The maximal inspiratory pressure variable increased significantly in the EG (+7.50 ± 1.72 cmH2O, p < 0.01, ES = 1.17), while no changes were observed in the CG. The LF/HF variable decreased significantly in the EG (−1.23 ± 0.34 n.u, p < 0.01, ES = 1.11), with no significant changes in the CG. The C Reactive Protein variable decreased significantly in the EG (−7.00 ± 3.07 mg/L, p < 0.01, ES = 1.4), with no significant changes in the CG. Conclusions: Six weeks of intermittent hypoxic–hyperoxic exposure was associated with trends toward improvements in blood pressure, respiratory function, cardiac autonomic nervous activity, and C Reactive Protein levels, compared with a placebo application of the same therapy.