TY - JOUR
T1 - Cyclical blood flow restriction resistance exercise
T2 - A potential parallel to remote ischemic preconditioning?
AU - Sprick, Justin D.
AU - Rickards, Caroline A.
N1 - Funding Information:
This study was supported, in part, by training fellowships awarded to Justin Sprick through a National Institutes of Health-supported Neurobiology of Aging Training Grant (T32 AG020494, principal investigator: M. Singh), and a Ruth L. Kirchstein National Research Service Award F31 Predoctoral Fellowship (1F31HL134242; principal investigator: J. D. Sprick), a UNTHSC Faculty Research Pilot Grant (principal investigator: C. A. Rickards), and a Texas Chapter of the American College of Sports Medicine (TACSM) Student Research Development Award (principal investigator: J. D. Sprick).
Publisher Copyright:
© 2017 the American Physiological Society.
PY - 2017/11
Y1 - 2017/11
N2 - Remote ischemic preconditioning (RIPC) is characterized by the cyclical application of limb blood flow restriction and reperfusion and has been shown to protect vital organs during a subsequent ischemic insult. Blood flow restriction exercise (BFRE) similarly combines bouts of blood flow restriction with low-intensity exercise and thus could potentially emulate the protection demonstrated by RIPC. One concern with BFRE, however, is the potential for an augmented rise in sympathetic outflow due to greater activation of the exercise pressor reflex. Because of the use of lower workloads, however, we hypothesized that BFRE would elicit an attenuated increase in sympathetic outflow [assessed via plasma norepinephrine (NE) and mean arterial pressure (MAP)] and middle cerebral artery velocity (MCAv) when compared with conventional exercise (CE). Fifteen subjects underwent two leg press exercise interventions: 1) BFRE-220 mmHg bilateral thigh occlusion at 20% 1 rep-max (1RM), and 2) CE-65% 1RM without occlusion. Each condition consisted of 4 × 5-min cycles of exercise, with 3 × 10-reps in each cycle. Five minutes of rest and reperfusion (for BFRE) followed each cycle. MAP increased with exercise (P < 0.001) and was 4–5 mmHg higher with CE versus BFRE (P ≤ 0.09). Mean MCAv also increased with exercise (P < 0.001) and was higher with CE compared with BFRE during the first bout of exercise only (P = 0.07). Plasma NE concentration increased with CE only (P < 0.001) and was higher than BFRE throughout exercise (P ≤ 0.02). The attenuated sympathetic response, combined with similar cerebrovascular responses, suggest that cyclical BFRE could be explored as an alternative to CE in the clinical setting.
AB - Remote ischemic preconditioning (RIPC) is characterized by the cyclical application of limb blood flow restriction and reperfusion and has been shown to protect vital organs during a subsequent ischemic insult. Blood flow restriction exercise (BFRE) similarly combines bouts of blood flow restriction with low-intensity exercise and thus could potentially emulate the protection demonstrated by RIPC. One concern with BFRE, however, is the potential for an augmented rise in sympathetic outflow due to greater activation of the exercise pressor reflex. Because of the use of lower workloads, however, we hypothesized that BFRE would elicit an attenuated increase in sympathetic outflow [assessed via plasma norepinephrine (NE) and mean arterial pressure (MAP)] and middle cerebral artery velocity (MCAv) when compared with conventional exercise (CE). Fifteen subjects underwent two leg press exercise interventions: 1) BFRE-220 mmHg bilateral thigh occlusion at 20% 1 rep-max (1RM), and 2) CE-65% 1RM without occlusion. Each condition consisted of 4 × 5-min cycles of exercise, with 3 × 10-reps in each cycle. Five minutes of rest and reperfusion (for BFRE) followed each cycle. MAP increased with exercise (P < 0.001) and was 4–5 mmHg higher with CE versus BFRE (P ≤ 0.09). Mean MCAv also increased with exercise (P < 0.001) and was higher with CE compared with BFRE during the first bout of exercise only (P = 0.07). Plasma NE concentration increased with CE only (P < 0.001) and was higher than BFRE throughout exercise (P ≤ 0.02). The attenuated sympathetic response, combined with similar cerebrovascular responses, suggest that cyclical BFRE could be explored as an alternative to CE in the clinical setting.
KW - Exercise for cardiac rehabilitation
KW - Exercise for stroke rehabilitation
KW - KAATSU
KW - Vascular occlusion training
UR - http://www.scopus.com/inward/record.url?scp=85032911555&partnerID=8YFLogxK
U2 - 10.1152/ajpregu.00112.2017
DO - 10.1152/ajpregu.00112.2017
M3 - Article
C2 - 28835448
AN - SCOPUS:85032911555
SN - 0363-6119
VL - 313
SP - R507-R517
JO - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
JF - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
IS - 5
ER -