Teresa Zwierko1, Damian Czepita, Wojciech Lubiński. 1. Department of Natural Sciences, University of Szczecin, Al. Piastów 40 b blok 6, 71-065 Szczecin, Poland. teresa.zwierko@univ.szczecin.pl
Abstract
BACKGROUND: The aim of our study was to assess the effect of physical exercise with increasing intensity on neuroretinal activity in healthy subjects (n = 30). METHOD: We analysed the amplitude and implicit time of b-wave electroretinogram (ERG) responses in two experiments: (1) for a scotopic blue 10 Hz flicker stimulus (rod-mediated responses), and (2) for a photopic white 30 Hz flicker stimulus (cone-mediated responses). Using a cycloergometer, three 10-minute effort-tests with increasing intensity were performed. Each participant was assigned individual workload values (W) below the lactate threshold (40% VO(2)max), at the lactate threshold (60-65% VO(2)max) and above the lactate threshold (80% VO(2)max). Five ERG recordings were taken: (1) before, (2-4) immediately after the three subsequent efforts and (5) 1 hour after the completion of the last effort. The right eye was selected for monocular stimulation in both experiments. RESULTS: After the first effort (40% VO(2)max), we observed an increased amplitude (p < 0.001) and decreased implicit time of the b-wave (p < 0.01) in cone-mediated responses, and no significant effects in rod-mediated responses. Despite the increase in effort intensity, the cone b-wave amplitude remained unchanged, whereas the rod b-wave amplitude significantly decreased after the subsequent efforts (p < 0.001). CONCLUSIONS: Rod-mediated responses were more susceptible to effort-induced homeostasis disruptions than the cone-mediated responses. The application of ERGs may be used as neurophysiological criteria in defining the cardiovascular status of the physical performance.
BACKGROUND: The aim of our study was to assess the effect of physical exercise with increasing intensity on neuroretinal activity in healthy subjects (n = 30). METHOD: We analysed the amplitude and implicit time of b-wave electroretinogram (ERG) responses in two experiments: (1) for a scotopic blue 10 Hz flicker stimulus (rod-mediated responses), and (2) for a photopic white 30 Hz flicker stimulus (cone-mediated responses). Using a cycloergometer, three 10-minute effort-tests with increasing intensity were performed. Each participant was assigned individual workload values (W) below the lactate threshold (40% VO(2)max), at the lactate threshold (60-65% VO(2)max) and above the lactate threshold (80% VO(2)max). Five ERG recordings were taken: (1) before, (2-4) immediately after the three subsequent efforts and (5) 1 hour after the completion of the last effort. The right eye was selected for monocular stimulation in both experiments. RESULTS: After the first effort (40% VO(2)max), we observed an increased amplitude (p < 0.001) and decreased implicit time of the b-wave (p < 0.01) in cone-mediated responses, and no significant effects in rod-mediated responses. Despite the increase in effort intensity, the cone b-wave amplitude remained unchanged, whereas the rod b-wave amplitude significantly decreased after the subsequent efforts (p < 0.001). CONCLUSIONS: Rod-mediated responses were more susceptible to effort-induced homeostasis disruptions than the cone-mediated responses. The application of ERGs may be used as neurophysiological criteria in defining the cardiovascular status of the physical performance.
Authors: Lukas M Mees; Monica M Coulter; Micah A Chrenek; Cara T Motz; Erica G Landis; Jeffrey H Boatright; Machelle T Pardue Journal: Invest Ophthalmol Vis Sci Date: 2019-04-01 Impact factor: 4.799