Physiological Response to a Training and Detraining Period in Vascular Parameters of Cardiometabolic Risk Factors Subjects: Optimizing Post-exercise Strategies to Maintain Health Benefits in Chilean Adults
Phase: NA
Conditions: Vascular Disease, Peripheral, Physical Inactivity, Arterial Hypertension, Endothelial Dysfunction
Sponsor: Cristian Alvarez

PHYSIOLOGICAL RESPONSE TO A TRAINING AND DETRAINING PERIOD 
IN VASCULAR PARAMETERS OF CARDIOMETABOLIC RISK FACTORS 
SUBJECTS: OPTIMIZING POST-EXERCISE STRATEGIES TO MAINTAIN 
HEALTH BENEFITS IN CHILEAN ADULTS 
 
Date: June 20th, 2022 
 
 
 
 
 
 
 
 
Study documents 
 
 
 
 
 
 
 
 
 
 

Scientific background: Atherosclerosis is a chronic disease characterized by the 
accumulation of lipid cells in the inner layer of artery walls, often as a result of oxidative 
damage to low-density lipoprotein (LDL-c) 1. LDL-c accumulation can lead to 
inflammation in the major arteries (e.g., carotid and brachial arteries), which usually 
progress to fibroatheromas 2. However, before the development of atherosclerosis, 
endothelial dysfunction (EDys) is a phenotypic (i.e., intermediate pathology condition) 
vascular alteration of the endothelium, characterized by a pro-thrombotic and pro-
inflammatory state as result of imbalance between the actions of vasodilators and 
vasoconstrictors, modifying thus both ‘function’ and ‘structure’ of the vasculature 3. 
Given that traditional methods for detecting EDys are highly invasive, expensive, and 
time-consuming 
(e.g., 
coronary 
epicardial 
vasoreactivity, 
venous 
occlusion 
plethysmography), non-invasive methods based on ultrasound imaging have been rapidly 
implemented in clinical management 4,5.   
EDys is often associated with several health conditions including arterial 
hypertension (HTN), obesity, coronary artery disease, chronic heart failure, peripheral 
artery disease, diabetes, metabolic syndrome, non-alcoholic fatty liver disease, and 
chronic renal failure 6. In Chile, 26.9% of adults are HTN, and this prevalence is highly 
superior in elderlies 7, therefore, it is estimated that an important number of adults and 
older adults will develop EDys, that will progress to atherosclerosis, or to an atheromatous 
plaque that in turn will increase the risk of stroke. From ‘functional’ parameters, the 
percentage of flow-mediated dilation (FMD) has been a more suitable a non-invasive and 
strong marker of vascular health in adults, where low values of FMD (i.e., <6.5%) denotes 
an impaired vascular function associated with cardiometabolic risk 4,8. To both 
‘functional’ and ‘structural’ modifications, the pulse wave velocity of the brachial artery 
(PWVba) is a recognized marker of arterial stiffness in adults , where >10 cm/s indicates 

high cardiovascular risk 9, and on the other hand, carotid-intima media thickness (cIMT) 
is a well established marker of structural vascular health 10. 
It is well known in physical inactivity (i.e., does not follow international physical 
activity guidelines of 300 min/week of low-moderate PA or at least 150 min/week of 
vigorous intensity [11,12]) is in higher prevalence in sedentary, obese, higher blood 
pressure, dyslipidaemias or suffering from metabolic syndrome, that there is a negative 
effect on both functional and structural vascular parameters such as FMD, PWVba, and 
cIMT 4. Relevant American and Latin American expert panels have recommended 
performing moderate intensity continuous training (MICT) for 30-60 minutes per session 
most days of the week in subjects with elevated blood pressure or HTN patients 11. In this 
sense, other experts have also confirmed that MICT is crucial for preventing and treating 
hypertension 12,13, and recent evidence highlight the time-efficient of high-intensity 
interval training 14,15, and resistance training for improving EDys similarly 16.   
However, before starting any exercise training program in clinical populations 
such as those with elevated blood pressure or HTN, it will necessary to know the baseline 
of the cardiovascular response to the physical effort through of a progressive exercise 
volitional test, such as a cycling test [16,17]. A progressive volitional cycling test like the 
Astrand test provides useful information about the cycling power output (PO) in watts, 
which increases at different levels (e.g., in women PO increases by 25 watts per level and 
in men it increases to 50 watts), while heart rate should also increase progressively at each 
level [17,18]. Interestingly, the theoretically predicted heart rate maximum (HRpredicted) 
using the well-known formula (i.e., 220-age) is often overestimated or underestimated in 
physically inactive individuals [19]. Additionally, the use of heart rate maximum (HRmax) 
is poorly reported in physically inactive hypertensive populations that are generally 
unable to maintain a steady state at maximal intensity. From here, the heart rate peak 

(HRpeak) is a useful marker of cardio-vascular condition and it has been widely used for 
exercise prescription in the future. The aim of this study was to assess the relationship 
between EDys markers (FMD, PWVba, and cIMT) and heart rate during a progressive 
volitional cycling test in adults with hypertension. A secondary aim was to characterize 
cardiovascular, anthropometric, and body composition outcomes in normotensive, 
elevated blood pressure, and hypertension patients. 
This study will follow the CONSORT guidelines for randomised trials, will be 
developed in accordance with the Declaration of Helsinki (2013), and has been approved 
by the BIOETICAL COMMITTEE OF UNIVERSIDAD ANDRES BELLO (Approval 
026/2022 of September 22th). Design: An experimental clinical randomized study. 
Methods: This study is an experimental randomized controlled clinical trial in which 
(n=75) adults (men and women) were invited to participate in an exercise training 
intervention and were assigned to one of three groups based on their blood pressure levels: 
arterial hypertension (HTN), elevated blood pressure (Ele), or to a normotensive control 
group (CG). The study took place in Concepción, Chile between September 2022 and 
January of 2023.  We used G*Power 3.1.9.7 statistical sample size software calculator, 
with an alpha error probability of p<0.05, and with 95% confidence interval (CI) for 3 
groups (expecting medium to-large effect size) for obtain the sample size. Thus, a 
minimum of ten subjects per group would give a statistical power of ≥90%)].  
The eligibility criteria for this study were: i) HTN, elevated blood pressure 
(controlled and on updated pharmacotherapy), or healthy normotensive; ii) normal 
weight, overweight, or obese (as determined by body mass index [BMI]); iii) normal or 
hyperglycaemic (T2DM, controlled and on updated pharmacotherapy); iv) living in urban 
areas of the city of Concepción; and v) demonstrated ability to adhere to all measurements 
and stages of the study. Exclusion criteria included: i) abnormal ECG; ii) uncontrolled 

HTN (SBP ≥169 mmHg or DBP >95 mmHg); iii) morbid obesity (BMI ≥40 kg/m2); iv) 
type 1 diabetes mellitus; v) cardiovascular disease (e.g., coronary artery disease); vi) 
diabetes complications such as varicose ulcers on the feet or legs, or a history of wounds, 
nephropathies, or muscle-skeletal disorders (e.g., osteoarthrosis); vii) recent participation 
in weight loss treatment or exercise training programs (within the past 3 months); and 
viii) use of pharmacotherapy that can influence body composition. All participants were 
informed about the study procedures and potential risks and benefits, and provided 
written consent. The study was conducted in accordance with the Declaration of Helsinki 
and was approved by the Ethics Committee of Universidad Andres Bello, Chile 
(Approval N° 026/2022). 
In the first stage of the enrollment (n=75) subjects were screened, and after 
exclusion criteria were applied (n=10) participants were excluded for various reasons 
([n=3] due to bone diseases, [n=3] due to a history of heart disease, and [n=3] because 
they were already enrolled in other exercise activities and (n=1) due to declared weight 
loss treatment). Thus, a total of (n=65) subjects participated in this first stage of our 
clinical trial study. The final sample size was as follows per group; (HTN n=18, Ele n=22, 
and CG n=21). 
 
REFERENCES 
1. 
Abulnaja KO, Kannan K, Al-Manzlawi AMK, Kumosani TA, Qari M, Moselhy 
SS. Sensitivity, specificity of biochemical markers for early prediction of endothelial 
dysfunction in atherosclerotic obese subjects. African Health Sciences 2022; 22(2): 286-
94. 
2. 
Collins R. Heart Protection Study of cholesterol-lowering with simvastatin in 
5963 people with diabetes: a randomised placebo-controlled trial. Lancet 2003; 361: 
2005-16. 
3. 
Restaino RM, Walsh LK, Morishima T, et al. Endothelial dysfunction following 
prolonged sitting is mediated by a reduction in shear stress. American Journal of 
Physiology-Heart and Circulatory Physiology 2016; 310(5): H648-H53. 
4. 
Thijssen DH, Bruno RM, van Mil AC, et al. Expert consensus and evidence-based 
recommendations for the assessment of flow-mediated dilation in humans. Eur Heart J 
2019; 40(30): 2534-47. 

5. 
Morales MS, Cuffaro PE, Barochiner J, et al. Validation of a new piezo-electronic 
device for non-invasive measurement of arterial pulse wave velocity according to the 
artery society guidelines. Artery research 2015; 10: 32-7. 
6. 
Bender SB, Laughlin MH. Modulation of endothelial cell phenotype by physical 
activity: impact on obesity-related endothelial dysfunction. American Journal of 
Physiology-Heart and Circulatory Physiology 2015; 309(1): H1-H8. 
7. 
Petermann F, Durán E, Labraña AM, et al. Factores de riesgo asociados al 
desarrollo de hipertensión arterial en Chile. Revista medica de Chile 2017; 145(8): 996-
1004. 
8. 
Heiss C, Rodriguez-Mateos A, Bapir M, Skene SS, Sies H, Kelm M. Flow-
mediated dilation reference values for evaluation of endothelial function and 
cardiovascular health. Cardiovascular Research 2022. 
9. 
Lee SJ, Avolio A, Seo DC, et al. Relationship Between Brachial‐Ankle Pulse 
Wave Velocity and Incident Hypertension According to 2017 ACC/AHA High Blood 
Pressure Guidelines. Journal of the American Heart Association 2019; 8(16): e013019. 
10. 
Stein JH, Korcarz CE, Hurst RT, et al. Use of Carotid Ultrasound to Identify 
Subclinical Vascular Disease and Evaluate Cardiovascular Disease Risk: A Consensus 
Statement from the American Society of Echocardiography Carotid Intima-Media 
Thickness Task Force Endorsed by the Society for Vascular Medicine. J Am Soc 
Echocardiog 2008; 21(2): 93-111. 
11. 
Bruneau ML, Johnson BT, Huedo-Medina TB, Larson KA, Ash GI, Pescatello 
LS. The blood pressure response to acute and chronic aerobic exercise: A meta-analysis 
of candidate gene association studies. Journal of science and medicine in sport 2016; 
19(5): 424-31. 
12. 
Pescatello LS, MacDonald HV, Lamberti L, Johnson BT. Exercise for 
hypertension: a prescription update integrating existing recommendations with emerging 
research. Current hypertension reports 2015; 17(11): 87. 
13. 
Condliffe S, Link CR, Parasuraman S, Pollack MF. The effects of hypertension 
and obesity on total health-care expenditures of diabetes patients in the United States. 
Applied Economics Letters 2013; 20(7): 649-52. 
14. 
Ramírez-Vélez R, Correa-Rodríguez M, Tordecilla-Sanders A, et al. Exercise and 
postprandial lipemia: effects on vascular health in inactive adults. Lipids in health and 
disease 2018; 17(1): 69. 
15. 
Ramírez-Vélez R, Hernández-Quiñones PA, Tordecilla-Sanders A, et al. 
Effectiveness of HIIT compared to moderate continuous training in improving vascular 
parameters in inactive adults. Lipids in health and disease 2019; 18(1): 42. 
16. 
Pedralli ML, Marschner RA, Kollet DP, et al. Different exercise training 
modalities produce similar endothelial function improvements in individuals with 
prehypertension or hypertension: a randomized clinical trial Exercise, endothelium and 
blood pressure. Scientific reports 2020; 10(1): 1-9. 
17. 
Hopkins WG, Marshall SW, Batterham AM, Hanin J. Progressive statistics for 
studies in sports medicine and exercise science. Medicine and science in sports and 
exercise 2009; 41(1): 3-13. 
18. 
Green DJ, Eijsvogels T, Bouts YM, et al. Exercise training and artery function in 
humans: nonresponse and its relationship to cardiovascular risk factors. Journal of 
Applied Physiology 2014; 117(4): 345-52. 
  
 

Statistical Analysis Plan (SAP): Data are presented as mean and (±) standard 
deviation (SD). The normality assumption for all variables was tested using the Shapiro–
Wilk test. Wilcoxon’s rank sum test was used for not normally distributed variables. A 
one-way ANOVA will be performed to test differences between groups and a post hoc 
[Sidack’s] test after ANOVA for group comparisons (i.e., HTN x Ele x CG). Additionally, 
we will report a trend analyses [ptrend] to test potential (linear) tendence to increase or 
decrease a particular outcome through these categories of different blood pressure. 
Finally, using the first three steps of the progressive volitional cycling Astrand test (i.e., 
25/50, 50/100, and 75/150 watt) we will apply a linear regression among EDys outcomes 
FMD, PWVba, cIMT to be associated with the heart rate (beats/min) in these three steps, 
and the R2 will be tested as predictive capacity from this heart rate for EDys outcomes. 
These analyses will be performed using Graph Pad Prism 8.0 software (Graph Pad 
Software, San Diego, CA, USA). The alpha level was set at p<0.05 for statistical 
significance.