A Single Dosage of l-Arginine Oral Supplementation Induced Post-Aerobic Exercise Hypotension in Hypertensive Patients

Abstract

Lowering of peripheral vascular resistance is one of the primary processes involved in blood pressure decrease. Nitric oxide plays a significant role in this process and the availability of l-arginine is a crucial element in nitric oxide biosynthesis. Oral l-arginine supplementation may therefore be a potentiating element in post-exercise hypotension, mediated by its vasodilator action. Thus, the purpose of this study was to investigate if a single dose of l-arginine oral supplementation might impact the post-aerobic exercise blood pressure responses in treated hypertensive individuals. A double-blind, randomized, placebo-controlled crossover trial was conducted. The sample included male (4) and female (6) subjects [62 ± 10 years]. The participants were randomized to ingest one sachet containing 8 grams of l-arginine or placebo (corn starch) dissolved in water (100 ml). The substances were self-administered 120 min before the experimental or control session. The exercise was conducted on a treadmill and consisted of: a 5 min warm-up (50-65% HRreserve); 40 min of running/walking at 60-70% HRreserve; and a 5 min progressive cooldown. After the exercise sessions, blood pressure was measured every 10 min for 60 min. The l-arginine supplementation arm led to significant post-exercise systolic hypotension (mean post-exercise) in relation to rest period (117 ± 12 vs 125 ± 15 mmHg - p = 0.004 [l-arginine] and 121 ± 11 vs 125 ± 15 - p = 0.341 [placebo]). In addition, a systolic net effect of −6.9 ± 3.6 mmHg [p = 0.046] was identified for the mean post-exercise values. Therefore, this study showed that a single dosage of l-arginine oral supplementation induced post-aerobic exercise hypotension in hypertensive patients.

Keywords:

• Arginine
• blood pressure
• exercise
• hypertension
• post-exercise hypotension

Acknowledgements

Fundação Nacional de Desenvolvimento do Ensino Superior Particular – FUNADESP and Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq.

Disclosure statement

The authors declare that they have no competing interests.

Funding

The author(s) reported there is no funding associated with the work featured in this article.

Trial registration

ClinicalTrials.gov NCT03378596

Additional information

Notes on contributors

Juliano Casonatto

Juliano Casonatto is an associate professor of Physical Education at University of Northern Paraná (UNOPAR), Londrina, Brazil, where he works as supervisor and professor in the graduate courses (master and doctoral) in (1) Rehabilitation Sciences and (2) Physical Exercise in the Health Promotion. He is the coordinator of Research Group in Physiology and Physical Activity (GEPEFAF) and reviewer of several peer-reviewed scientific journals. He is a research productivity scholarship and a consultant on research projects from the National Foundation for Development of Private Education (FUNADESP). Juliano’s research is focused on the physiological responses arising from exercise and nutritional strategies.

João Vagner Cavalari

João Vagner Cavalari is an adjunct professor at University of Northern Paraná (UNOPAR), Londrina, Brazil, where he works as professor in the undergraduate courses (Physical Education). He is a member of Research Group in Physiology and Physical Activity (GEPEFAF). He also works as a teacher in Basic Education in the public education system. João’s research is focused on the impact of different physiological strategies on cardiovascular function.