Test‐retest reliability of eucapnic voluntary hyperpnea test performance and pre‐post spirometry in elite swimmers (LB783)

Abstract

Test‐retest reliability of eucapnic voluntary hyperpnea test performance and pre‐post spirometry in elite swimmers Michael D. Kennedy1, Craig D. Steinback1, Rachel Skow1, Eric C. Parent2. 1Faculty of Physical Education and Recreation, 2Department of Physical Therapy, University of Alberta, Edmonton, Alberta, Canada.Exercise induced bronchoconstriction (EIB) is common in “high ventilation” athletes and a 6 min Eucapnic Voluntary Hyperpnea (EVH) airway provocation (30 breaths/min; Tidal Volume (TV) of 85% FEV1; 100% dry medical air) is the standard EIB screen. Sensitivity of EVH is well documented; however, test‐retest reliability of spirometry measurements and EVH performance has not been determined.Swimmers (n=11; 5/6 m/f) with 蠅13 yrs of competitive experience completed spirometry (FEV1) before and 45 sec, 5, 10, 20 min after an EVH test on 2 consecutive days.Overall pre‐test FEV1 was decreased on Day 2 (Day 1 4.6±0.8 vs. Day 2 4.5±0.7L, p = 0.04) and this pre‐test FEV1 decrease occurred in 9/11 swimmers (range ‐ 370 (6.8%) to ‐ 30ml (0.6%); with excellent agreement in pre‐test FEV1 between days (ICC 0.97 (0.90 ‐ 0.99, 95% confidence interval). Swimmers achieved 85±9% and 87±9% of target TV on Day 1 and 2 respectively (p = 0.45; ICC 0.57 (0.00 – 0.86)) resulting in a total ventilation of 687 vs 684L (p = 0.89, ICC 0.89 (0.65 – 0.97)) equating to 82±8% and 84±9% of predicted total volume (ICC 0.54 (0.00 – 0.85) between Day 1 and Day 2. Day 1 and 2 post‐test FEV1 were not different at any time point however 4 swimmers were positive for EIB (> 15% fall in pre‐post FEV1) and these swimmers post‐test FEV1 was 10.6 to 1.9% less on Day 2. Post‐test ICC for FEV1 were 0.97 (0.91‐0.99), 0.97 (0.89‐0.99), 0.97 (0.88‐0.99) and 0.94 (0.81‐0.98) at 45s, 5min, 10min, and 20 min respectively.Overall, strong test‐retest reliability was found for FEV1 and total ventilation; despite a significant decrease in pre‐test FEV1 on Day 2. Post‐test FEV1 is likely more reliable early post‐test (45s, 5min, 10min) than at 20min post‐test.