Absence of Respiratory Muscle Fatigue in High-Intensity Continuous or Interval Cycling Exercise. Issue 11 (November 2015)

• Record Type: Journal Article
• Authors: Kurti, Stephanie P.; Smith, Joshua R.; Emerson, Sam R.; Castinado, Kenneth M.; Harms, Craig A.
• Is Part Of: Journal of strength and conditioning research. Volume 29:Issue 11(2015)
• Publication Date: 2015-11
• Subjects: high-intensity intervals -- pulmonary -- exercise training -- exercise physiology; Physical education and training -- Periodicals; Weight training -- Physiological aspects -- Periodicals; Physical fitness -- Periodicals; 613.7
• DOI: 10.1519/JSC.0000000000000974
• Languages: English
• ISSNs: 1064-8011

Abstract

Abstract : Abstract: Kurti, SP, Smith, JR, Emerson, SR, Castinado, KM, and Harms, CA. Absence of respiratory muscle fatigue in high-intensity continuous or interval cycling exercise. J Strength Cond Res 29(11): 3171–3176, 2015—Respiratory muscle fatigue (RMF) occurs during prolonged exercise (∼15–20 minutes) at >85% V[Combining Dot Above]O2 max. However, RMF has been reported to occur in ∼3–6 minutes in various modes of exercise at a high intensity. It is not known if continuous cycling exercise vs. repeated bouts of high-intensity interval training (HIT) at >85% V[Combining Dot Above]O2 max will lead to RMF. We hypothesized that RMF would occur after a constant load test and would be present before end exercise in an HIT protocol. Eight moderately active healthy men (21.7 ± 1.7 years; 181.3 ± 5.2 cm; 81.3 ± 2.3 kg) completed a V[Combining Dot Above]O2 max test on a cycle ergometer. Subjects then completed 2 bouts of HIT (7 × 1 minute, 2-minute recovery between intervals) and 3 bouts of continuous exercise (CE) tests at 90% of peak power (determined from an incremental exercise test to exhaustion). Maximal inspiratory pressure (PIMAX ) and expiratory pressure (PEMAX ) were measured pre- and post-exercise for both HIT and CE and after each interval during HIT. Decreases in postexercise PIMAX and PEMAX compared with baseline were used to determine RMF. There were no differences ( p > 0.05) in PIMAX or PEMAX pre- to post-exercise for HIT (PIMAX pre: 134 ± 51, post: 135 ± 50 cmH2 O; PEMAX pre: 143 ± 41, post: 148 ± 46 cmH2 O) or CE (PIMAX pre: 135 ± 54, post: 133 ± 52 cmH2 O; PEMAX pre: 146 ± 46, post: 148 ± 46 cmH2 O) indicating RMF was not present following CE and HIT. These data suggest that repeated high-intensity cycling exercise at 90% peak power in a CE or HIT protocol does not lead to RMF.