ABC | Volume 113, Nº2, August 2019

Original Article Casonatto et al. Citrulline and post-exercise hypotension Arq Bras Cardiol. 2019; 113(2):218-228 1. KenneyMJ, Seals DR. Postexercise hypotension. Key features, mechanisms, and clinical significance. Hypertension. 1993;22(5):653-64. 2. RondonMUB, Alves MJ, Braga AM, TeixeiraOT, Barretto AC, Krieger EM, et al. Postexercise blood pressure reduction in elderly hypertensive patients. J Am Coll Cardiol. 2002;39(4):676-82. 3. Halliwill JR, Buck TM, Lacewell AN, Romero SA. Postexercise hypotension and sustained postexercise vasodilatation: what happens after we exercise? Exp Physiol. 2013;98(1):7-18. 4. Hecksteden A, Grutters T, Meyer T. Association between postexercise hypotension and long-term training-induced blood pressure reduction: a pilot study. Clin J Sport Med. 2013;23(1):58-63. 5. Kiviniemi AM, Hautala AJ, Karjalainen JJ, Piira OP, Lepojarvi S, Ukkola O, et al. Acute post-exercise change in blood pressure and exercise training response in patients with coronary artery disease. Front Physiol. 2015 Jan 12;5:526. 6. Moreira SR, Cucato GG, Terra DF, Ritti-Dias RM. Acute blood pressure changes are related to chronic effects of resistance exercise in medicated hypertensives elderly women. Clin Physiol Funct Imaging. 2016;36(3):242-8. 7. Liu S, Goodman J, Nolan R, Lacombe S, Thomas SG. Blood pressure responses to acute and chronic exercise are related in prehypertension. Med Sci Sports Exerc. 2012;44(9):1644-52. 8. Tibana RA, de Sousa NM, da Cunha Nascimento D, Pereira GB, Thomas SG, Balsamo S, et al. Correlation between acute and chronic 24-hour blood pressure response to resistance training in adult women. Int J Sports Med. 2015;36(1):82-9. 9. Costa EC, Dantas TC, de Farias Junior LF, FrazaoDT, Prestes J, Moreira SR, et al. Inter- and intra-individual analysis of post-exercise hypotension following a single bout of high-intensity interval exercise and continuous exercise: a pilot study. Int J Sports Med. 2016;37(13):1038-43. References Despite the interesting findings of this study, it is important to consider that there is no consensus to distinguish “responders” from “non-responders” due to the lack of agreement on whether to define “response” as a clinically relevant change or a clearly measurable change. 41 Additionally, BP measurements incorporate some degree of error (instrumentation noise + biological noise), and changes can often occur due to factors independent of the intervention (biological variability). 42 For this reason, the authors decided not to apply a theoretical construct (based on SD, confidence intervals, or smallest worthwhile change) to determine the extent to which changes were the direct result of the intervention or effectively "random" external causes. On the other hand, it is important to highlight that independent of the theoretical measurement error degree adopted, the EC group presented more "responsive" individuals in all hypothetical situations. Some limitations of this study should be considered. The results from the few available studies differ considerably, making comparisons somewhat difficult. Although drug therapies were not changed during the study, patients were using different types of medication, and this factor might have affected the results. Moreover, it is recommended that future studies include NO availability measurements, such as nitrite and nitrate. These measurements associated with the evaluation of important mechanisms such as peripheral vascular resistance and cardiac output might help us to understand the citrulline action combined with exercise in hypertensives. Conclusion These results suggest that acute CM supplementation can increase the post-exercise hypotensive effects in hypertensives. In addition, the prevalence of non‑responders is lower when associating aerobic exercise and CM supplementation. Clinical messages • There was considerable inter-individual responsiveness variability in systolic and diastolic BP responses following all experimental protocols. • Despite the inter-individual responsiveness variability, therewas a PEHpotentiationby theCMsupplementation. Author contributions Conception and design of the research, Statistical analysis and Obtaining financing: Casonatto J; Acquisition of data: Enokida DM, Grandolfi K; Analysis and interpretation of the data: Casonatto J, Enokida DM, Grandolfi K; Writing of the manuscript: Casonatto J, Enokida DM; Critical revision of the manuscript for intellectual content: Grandolfi K. Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding This study was funded by FUNADESP. Study Association This article is part of the thesis of master submitted by Daniel Massaharu Enokida, from Universidade Norte do Paraná. Ethics approval and consent to participate This study was approved by the Ethics Committee of the Universidade Norte do Paraná under the protocol CAAE: 78697617.4.0000.0108 – Appraisal number: 2.593.090. All the procedures in this study were in accordance with the 1975 Helsinki Declaration, updated in 2013. Informed consent was obtained from all participants included in the study. 226