Sara R Sherman1, Wesley K Lefferts1,2, Elizabeth C Lefferts1,2, Georgios Grigoriadis1, Natalia S Lima1, Bo Fernhall1, Tracy Baynard1, Alexander J Rosenberg3,4,5. 1. Integrative Physiology Laboratory, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, IL, USA. 2. Clinical Vascular Research Laboratory, Department of Kinesiology, Iowa State University, Ames, IA, USA. 3. Integrative Physiology Laboratory, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, IL, USA. arosen@midwestern.edu. 4. Cerebral and Cardiovascular Physiology Laboratory, University of North Texas Health Science Center at Fort Worth, Fort Worth, TX, USA. arosen@midwestern.edu. 5. Department of Physiology, Midwestern University, Downers Grove, IL, USA. arosen@midwestern.edu.
Abstract
INTRODUCTION: Age-related stiffening of the large elastic arteries (e.g., common carotid artery [CCA]) may impair wall dynamics (i.e., strain) and amplify transmission of pulsatile blood flow into the brain with large increases in pressure that occur during maximal resistance exercise (RE). The purpose of this study was to compare CCA arterial wall dynamics, central hemodynamics, and cerebral blood velocity responses during maximal RE between young and older adults. METHODS: Thirty-one young (YA; 26 ± 5 yrs; 23.8 ± 3.3 kg/m2) and 25 older adults (OA; 60 ± 6 yrs; 30.0 ± 5.5 kg/m2) performed a unilateral maximal isokinetic knee flexion/extension exercise protocol (i.e., maximal RE). All measures were recorded at baseline and during the last 10 s of maximal RE. Common carotid artery strain, CCA strain time to peak, and CCA strain rate (i.e., variables of arterial wall dynamics) were analyzed using 2D speckle tracking software from circumferential ultrasound images. Transcranial Doppler was used to measure right middle cerebral artery (MCA) blood velocity. Non-invasive arterial blood pressure measurements were obtained using finger photoplethysmography. RESULTS: Older adults had greater reductions in CCA strain time to peak from baseline to maximal RE (345 ± 39 to 242 ± 52 ms) than YA (308 ± 35 to 247 ± 42 ms; interaction effect, p < 0.01). MCA velocity was similar between YA and OA during maximal RE (p = 0.48), despite a greater arterial pressor response in OA (p < 0.01). CONCLUSION: These data suggest cerebral blood velocity responds similarly during maximal RE among OA compared to YA, despite subtle age-related differences in the pressor and extracranial vascular response during maximal RE.
INTRODUCTION: Age-related stiffening of the large elastic arteries (e.g., common carotid artery [CCA]) may impair wall dynamics (i.e., strain) and amplify transmission of pulsatile blood flow into the brain with large increases in pressure that occur during maximal resistance exercise (RE). The purpose of this study was to compare CCA arterial wall dynamics, central hemodynamics, and cerebral blood velocity responses during maximal RE between young and older adults. METHODS: Thirty-one young (YA; 26 ± 5 yrs; 23.8 ± 3.3 kg/m2) and 25 older adults (OA; 60 ± 6 yrs; 30.0 ± 5.5 kg/m2) performed a unilateral maximal isokinetic knee flexion/extension exercise protocol (i.e., maximal RE). All measures were recorded at baseline and during the last 10 s of maximal RE. Common carotid artery strain, CCA strain time to peak, and CCA strain rate (i.e., variables of arterial wall dynamics) were analyzed using 2D speckle tracking software from circumferential ultrasound images. Transcranial Doppler was used to measure right middle cerebral artery (MCA) blood velocity. Non-invasive arterial blood pressure measurements were obtained using finger photoplethysmography. RESULTS: Older adults had greater reductions in CCA strain time to peak from baseline to maximal RE (345 ± 39 to 242 ± 52 ms) than YA (308 ± 35 to 247 ± 42 ms; interaction effect, p < 0.01). MCA velocity was similar between YA and OA during maximal RE (p = 0.48), despite a greater arterial pressor response in OA (p < 0.01). CONCLUSION: These data suggest cerebral blood velocity responds similarly during maximal RE among OA compared to YA, despite subtle age-related differences in the pressor and extracranial vascular response during maximal RE.
Authors: Georgios Grigoriadis; Alexander J Rosenberg; Wesley K Lefferts; Sang Ouk Wee; Elizabeth C Schroeder; Tracy Baynard Journal: Int J Sports Med Date: 2020-01-05 Impact factor: 3.118
Authors: Kevin S Heffernan; Sae Young Jae; David G Edwards; Erin E Kelly; Bo Fernhall Journal: Appl Physiol Nutr Metab Date: 2007-04 Impact factor: 2.665
Authors: Jane M Black; Eric J Stöhr; Keeron Stone; Christopher J A Pugh; Mike Stembridge; Rob Shave; Joseph I Esformes Journal: Physiol Rep Date: 2016-09