Intra-rater reliability and repeatability of pulse oximetry values obtained before, between sets, and after resistive exercise

BACKGROUND: Pulse oximetry measures heart rate (HR) and percent oxygen saturation (SpO[Formula: see text]). For aerobic exercise, whereby cellular oxygen demand and delivery are elevated and maintained for extended periods, HR and SpO[Formula: see text] values are consistent when measured by pulse oximetry. Yet due to its intermittent nature, HR and SpO[Formula: see text] values from resistive exercise may exhibit lower data reliability and repeatability. OBJECTIVE: Assess intra-rater reliability and repeatability of pulse oximetry HR and SpO[Formula: see text] values from two identical resistive exercise protocols. METHODS: Subjects ([Formula: see text] 32) performed two calf press workouts on a flywheel-based ergometer as HR and SpO[Formula: see text] were measured before, between sets, and after exercise. Workouts entailed a 4-set 15-repetition protocol separated by 120-second rests. Intra-rater reliability was assessed with intraclass correlation coefficients (ICC). Repeatability was measured by the smallest real difference in absolute and relative terms. RESULTS: ICC and standard error of estimate results for HR ranged from 0.60–0.79 and 9.1–13.0 respectively. SpO[Formula: see text] ICC and standard error of estimate results ranged from 0.16–0.71 and 1.44–4.33 respectively. Between sets, smallest real difference values tended to be less for HR. CONCLUSIONS: Results demonstrate acceptable intra-rater reliability and repeatability for HR, but not SpO[Formula: see text] which we attribute to the exercise mode and protocol examined.