The Effects of Whole Body Vibration Combined with L-Citrulline Supplementation on Arterial Stiffness, Pressure Wave Reflection, Endothelial Function and Body Composition in Overweight/Obese Postmenopausal Women

• Other Authors: Wong, Alexei (authoraut)
• Format: Others
• Language: English; English
• Published: Florida State University
• Subjects: Nutrition; Food; Exercise
• Online Access: http://purl.flvc.org/fsu/fd/FSU_migr_etd-8919

Arterial stiffness (pulse wave velocity [PWV]) and endothelial dysfunction contribute to the development of cardiovascular disease (CVD), which is currently afflicting millions of individuals. The use of the amino acid L-citrulline has been suggested as a potential aid for the treatment of CVD by increasing endothelial production of Nitric Oxide (NO). Whole body vibration (WBV) is new and effective form of exercise that is feasible for clinical populations and has been proven to decrease BP and arterial stiffness and increase muscle mass and strength. Therefore, the purpose of this study was to investigate if the combination of WBV training (WBVT) plus L-citrulline supplementation would induce positive additive effects and would be an effective means to ameliorate arterial stiffness, endothelial function, BP and muscle strength/mass in postmenopausal women. PURPOSE: The aim of this study was threefold. 1) to evaluate the effects of 8 weeks of WBVT combined with L-citrulline supplementation on hemodynamics and arterial function, 2) to evaluate the effects of WBVT combined with L-citrulline supplementation on muscle mass and strength, and 3) to measure endothelial function by assessing plasma NOx in order to examine the potential mechanisms by which WBVT and/or L-citrulline, decreases BP, arterial stiffness and wave reflection. METHODS: Forty-one postmenopausal women (age, 58 ± 3 years, body mass index; 34 ± 2 kg/m2) were randomized into 3 experimental intervention groups, L-citrulline, WBVT+L-citrulline and WBVT+Placebo for 8 weeks. WBVT consisted of 3 supervised training sessions a week. In regards to supplementation, subjects used 6 grams/day of oral L-citrulline or Placebo (maltodextrin). Brachial systolic BP (SBP), brachial diastolic BP (DBP), brachial mean arterial pressure (MAP), brachial pulse pressure (PP),aortic SBP, aortic DBP, aortic MAP, aortic PP, heart rate, augmented pressure (AP), augmentation index (AIx), AIx adjusted to 75 beats per minute (AIx@75), carotid-femoral PWV (aortic PWV), brachial-ankle PWV (baPWV), femoral-ankle PWV (legPWV), plasma NO metabolites (NOx), leg fat mass (FM), arm FM, total FM, leg lean mass (LM), arm LM, total LM, leg strength and arm strength were measured before and after 8 weeks of the assigned intervention. RESULTS: The WBVT+L-citrulline group significantly decreased (-0.9 ± 0.2 m/sec, p< .05) aortic PWV compared with no changes after WBVT+Placebo and L-citrulline groups. The WBVT+L-citrulline and WBVT+Placebo significantly decreased (p< .01) AIx and AIx @75 compared to baseline. However, the change in AIx@75 in the WBVT+L-citrulline was significantly (-10 ± 2%, p< .05) different compared with no changes in the L-citrulline group. In addition, the WBVT+L-citrulline and WBVT+Placebo groups significantly increased (p< .01) leg strength and this increase was significantly different than the no change seen after L-citrulline. All 3 groups significantly (p< .05) decreased BSBP,BDBP, BMAP, ASBP, ADBP, AMAP, AP, NOx, leg PWV and baPWV compare to baseline, but no difference among groups was found. Leg LM significantly increased (0.9 ± 0.3 Kg, p< .05) in the WBVT+L-citrulline only, but this change was not different than the other groups. Arm strength, leg FM, arm FM, total FM, arm LM, total LM were not significantly (p>.05) affected by any of the 3 interventions CONCLUSION: We showed that WBVT combined with L-citrulline supplementation decreases both brachial and aortic BP, legPWV, baPWV and AIx but does not amplify these changes compared to the other interventions. The present study demonstrates that the combination of WBVT and L-citrulline supplementation decreases aortic PWV, an effect that was not accomplished by either intervention alone. In addition, the combination of WBVT and L-citrulline supplementation decreases AIx@75, which was significantly different than the L-citrulline group. Furthermore, an increase in leg lean mass was observed with the combination treatment. In conclusion, WBVT combined with L-citrulline supplementation may be a feasible adjuvant treatment to decrease arterial dysfunction and may have a potential role in the prevention and treatment of sarcopenia. Further research is warranted in order to evaluate the effects of the combination of WBVT and L-citrulline in different populations at increased cardiovascular and sarcopenic risk. === A Dissertation submitted to the Department of Nutrition, Food and Exercise Sciences in partial fulfillment of the requirements for the degree of Doctor of Philosophy. === Spring Semester, 2014. === February 20, 2014. === Arterial Stiffness, Endothelial Function, Whole Body Vibration === Includes bibliographical references. === Arturo Figueroa, Professor Directing Dissertation; Gershon Tenebaum, University Representative; Michael Ormsbee, Committee Member; Maria Spicer, Committee Member.