Autonomic recovery following sprint interval exercise

Department of Medicine, McMaster University, Hamilton, Ontario, CanadaCorresponding author: Tordi Nicolas, PhD, EA 3920 - Explorations Fonctionnelles Respiratoires, 2 place St Jacques, 25030Besancon cedex, France. Tel: 33 3 81 21 87 50, Fax: 33 3 81 21 87 46, E-mail: nicolas.tordi@univ-fcomte.frAccepted for publication 22 February 2011The autonomic nervous activity was assessed followingsupramaximal exercise through heart rate (HR) and bloodpressure (BP) variability (HRV and BPV) and baroreflexsensitivity (BRS). The beat-to-beat HR and BP wererecorded during the supine and standing states before(PRE) and at 60 (R60) and 120min (R120) following single(one Wingate, 1W) and multiple sprint intervals (fourWingates interspersed with 4min of light cycling, 4W).The supine low frequency (LF) component was increased(Po0.001) and the high frequency (HF) was reduced(Po0.01) at R60 (LF, 178.1 11.0; HF, 74.8 10.5)compared with PRE (LF, 140.2 7.4; HF, 110.4 7.2)afterbothexercises.SupinesystolicBPVLF:HFwashigherat R60 (4.6 1.4) compared with PRE (6.8 2.4) onlyafter4W(P50.035).Supine BRSwaslower(Po0.001)atR60 (6.8 1.1) than at PRE (15.3 1.8) and R120(11.3 1.3). BRS at R120 remained lower after 4W(P50.02). Standing BRS was less (Po0.001) at R60(2.3 0.5) than at PRE (5.6 0.8) or R120 (3.7 0.6)and returned to PRE values only after 1W. We concludedthat (a) autonomic balance is shifted to a greater sympa-thetic and less parasympathetic activation following bothtypes of exercise, (b) it takes longer than 1h to recoverfollowing supramaximal exercise and (c) the recovery islonger after 4W than 1W.