New Insights into Cardiovascular and Exercise Physiology

A special issue of Life (ISSN 2075-1729). This special issue belongs to the section "Physiology and Pathology".

Deadline for manuscript submissions: closed (31 October 2023) | Viewed by 32937

Special Issue Editors


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Guest Editor
Faculty of Medicine, Institute of Physiology, University of Ljubljana, Ljubljana, Slovenia
Interests: cardiovascular physiology; microcirculation; sports physiology; endurance; endothelium; laser doppler; iontophoresis; wavelet analysis; heart rate variability; hyperglycemia; oral glucose tolerance test; cardiopulmonary exercise testing (CPET); VO2 max
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Guest Editor
1. Scientific Center of Excellence for Personalized Health Care, Josip Juraj Strossmayer University of Osijek, HR-31000 Osijek, Croatia
2. Department of Physiology and Immunology, Faculty of Medicine Osijek, Josip Juraj Strossmayer University of Osijek, HR-31000 Osijek, Croatia
Interests: microcirculation; n-3 PUFAs; endothelium; oxidative stress; eicosanoids; nutrients; exercise
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Cardiovascular physiology is a huge and, at a first glance, rather heterogenous area encompassing the closed circuit of the heart and vessels, each presenting with their unique features. However, it is the fine orchestrated interplay of all players that enables a proper supply of nutrients and oxygen to tissues according to their current needs and thus normal functioning of the organism. Aside from the systemic circulation that has mostly been investigated, far less is known about the pulmonary circulation, which undoubtedly represents an important circuit. The capacity of the cardiovascular system to adjust to varying needs is immense.

Although a lot of new mechanisms on the micro- as well on the macro-scale have been revealed in recent years, also due to the evolvement of modern techniques, and new concepts are emerging almost daily, there are still a lot of controversies and enigmas. The never-ending challenge remains how to translate the findings obtained in cell cultures and studies using animal models into human physiology. In this respect, in vivo studies on humans are encouraged as they in fact reflect the real situation and could strongly support the clinical work.

In light of the increasing incidence of cardiovascular diseases, the major cause of death worldwide, and the need to accomplish treatment strategies, the knowledge on physiological processes remains the basis for future research and is a prerequisite for upgraded clinical studies.

Physical exercise has increasingly been regarded as one of the potentially beneficial measures to improve cardiovascular health, interfering with numerous elements of the cardiovascular system and implying a multitude of potential mechanisms. Its long-term beneficial effects are well known; nevertheless, a lot of questions remain unresolved. Where is the line between benefit and harm? How do different types of exercise affect the cardiovascular system in health and disease, which is the most appropriate measure in terms of duration, repetition, and recovery, and whether and how should exercise be individually adjusted?

Accordingly, this Special Issue would like to attract scientists from various fields of cardiovascular and/or exercise physiology to present their new findings, from the gene and molecular to the cellular level and up to investigations in humans, each importantly contributing a puzzle to the whole mosaic, to discuss potential controversies and open challenges and questions for future research.

We encourage researchers to submit their findings, either in the form of original research or review articles.

Dr. Helena Lenasi
Prof. Dr. Ines Drenjančević
Guest Editors

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Keywords

  • exercise
  • cardiovascularsystem
  • epigeneticmodifications
  • microcirculation
  • microRNA
  • glucosemetabolism
  • insulinsensitivity
  • arterialbloodpressure
  • oxidativestress
  • exerkines
  • diet
  • inflammation

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Published Papers (12 papers)

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Research

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16 pages, 1364 KiB  
Article
The Effect of Acute Hyperglycaemia Induced by Oral Glucose Load on Heart Rate Variability and Skin Microvascular Reactivity in Young Adults
by Jernej Šorli and Helena Lenasi
Life 2024, 14(1), 56; https://doi.org/10.3390/life14010056 - 28 Dec 2023
Viewed by 1141
Abstract
We aimed to elucidate the effects of acute hyperglycaemia, induced by an oral glucose tolerance test (OGTT), on the autonomic nervous system (ANS) and skin microvascular reactivity at the time point of peak plasma glucose concentration (cglc) in 20 young, healthy [...] Read more.
We aimed to elucidate the effects of acute hyperglycaemia, induced by an oral glucose tolerance test (OGTT), on the autonomic nervous system (ANS) and skin microvascular reactivity at the time point of peak plasma glucose concentration (cglc) in 20 young, healthy participants. We assessed their heart rate variability (HRV) as a measure of the ANS activity and the parameters of post-occlusive reactive hyperaemia (PORH) to estimate skin microvascular reactivity as measured by laser Doppler (LD) fluxmetry. The tests were repeated 30 min after a standard OGTT (75 g glucose dissolved in 250 mL water) and, in a separate control experiment, after drinking the same amount of water. Participants had their cglc and serum insulin measured at three consecutive time-points according to the testing protocol. The low-frequency (LF) spectral power, the LF to high-frequency (LF/HF) ratio, and the diastolic blood pressure increased significantly more after water than after OGTT, and there was a trend of the peak LD flux of PORH decreasing more after OGTT than after water. Significant correlations between some PORH and all the HRV parameters and cglc increase after OGTT were found, implying diminished vascular reactivity evoked by hyperglycaemia in healthy subjects with lower glucose tolerance. Full article
(This article belongs to the Special Issue New Insights into Cardiovascular and Exercise Physiology)
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16 pages, 1659 KiB  
Article
Enhanced Microvascular Adaptation to Acute Physical Stress and Reduced Oxidative Stress in Male Athletes Who Consumed Chicken Eggs Enriched with n-3 Polyunsaturated Fatty Acids and Antioxidants—Randomized Clinical Trial
by Luka Kolar, Petar Šušnjara, Marko Stupin, Ana Stupin, Ivana Jukić, Zrinka Mihaljević, Nikolina Kolobarić, Iva Bebek, Diana Nejašmić, Marija Lovrić and Ines Drenjančević
Life 2023, 13(11), 2140; https://doi.org/10.3390/life13112140 - 31 Oct 2023
Cited by 1 | Viewed by 1761
Abstract
This randomized interventional study aimed to determine the effects of n-3 polyunsaturated fatty acids, selenium, vitamin E, and lutein supplementation in the form of enriched chicken egg consumption on microvascular endothelium-dependent vasodilation, oxidative stress, and microvascular response to an acute strenuous training session [...] Read more.
This randomized interventional study aimed to determine the effects of n-3 polyunsaturated fatty acids, selenium, vitamin E, and lutein supplementation in the form of enriched chicken egg consumption on microvascular endothelium-dependent vasodilation, oxidative stress, and microvascular response to an acute strenuous training session (ASTS) in competitive athletes. Thirty-one male athletes were assigned to a control (n = 17) or a Nutri4 group (n = 14) who consumed three regular or enriched chicken eggs per day, respectively, for 3 weeks. Significantly enhanced endothelium-dependent responses to vascular occlusion (PORH) and iontophoresis of acetylcholine (AChID) were observed in the Nutri4 group but not in the control group after egg consumption. Formation of peroxynitrite and hydrogen peroxide in peripheral blood mononuclear cells, as well as serum concentration of 8-iso prostaglandin F2α, decreased in the Nutri4 group while remaining unchanged in controls. PORH and AChID were reduced post-ASTS compared with pre-ASTS, both before and after the diets, in both groups. However, the range of PORH responsiveness to ASTS (ΔPORH) increased after consumption of enriched eggs. These results suggest that consumption of enriched chicken eggs has a beneficial effect on microvascular endothelium-dependent vasodilation and the reduction of oxidative stress levels in competitive athletes. Also, microvascular adaptation to the ASTS was improved after consumption of Nutri4 eggs. Full article
(This article belongs to the Special Issue New Insights into Cardiovascular and Exercise Physiology)
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17 pages, 1806 KiB  
Article
Cardiopulmonary Exercise Testing in Patients with Heart Failure: Impact of Gender in Predictive Value for Heart Transplantation Listing
by Pedro Garcia Brás, António Valentim Gonçalves, João Ferreira Reis, Rita Ilhão Moreira, Tiago Pereira-da-Silva, Pedro Rio, Ana Teresa Timóteo, Sofia Silva, Rui M. Soares and Rui Cruz Ferreira
Life 2023, 13(10), 1985; https://doi.org/10.3390/life13101985 - 29 Sep 2023
Cited by 2 | Viewed by 1693
Abstract
Background: Exercise testing is key in the risk stratification of patients with heart failure (HF). There are scarce data on its prognostic power in women. Our aim was to assess the predictive value of the heart transplantation (HTx) thresholds in HF in women [...] Read more.
Background: Exercise testing is key in the risk stratification of patients with heart failure (HF). There are scarce data on its prognostic power in women. Our aim was to assess the predictive value of the heart transplantation (HTx) thresholds in HF in women and in men. Methods: Prospective evaluation of HF patients who underwent cardiopulmonary exercise testing (CPET) from 2009 to 2018 for the composite endpoint of cardiovascular mortality and urgent HTx. Results: A total of 458 patients underwent CPET, with a composite endpoint frequency of 10.5% in females vs. 16.0% in males in 36-month follow-up. Peak VO2 (pVO2), VE/VCO2 slope and percent of predicted pVO2 were independent discriminators of the composite endpoint, particularly in women. The International Society for Heart Lung Transplantation recommended values of pVO2 ≤ 12 mL/kg/min or ≤14 if the patient is intolerant to β-blockers, VE/VCO2 slope > 35, and percent of predicted pVO2 ≤ 50% showed a higher diagnostic effectiveness in women. Specific pVO2, VE/VCO2 slope and percent of predicted pVO2 cut-offs in each sex group presented a higher prognostic power than the recommended thresholds. Conclusion: Individualized sex-specific thresholds may improve patient selection for HTx. More evidence is needed to address sex differences in HF risk stratification. Full article
(This article belongs to the Special Issue New Insights into Cardiovascular and Exercise Physiology)
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10 pages, 557 KiB  
Article
The Effect of Caffeine on Heart Rate Variability in Newborns: A Pilot Study
by Helena Lenasi, Eva Rihar, Jerneja Filipič, Matjaž Klemenc and Petja Fister
Life 2023, 13(7), 1459; https://doi.org/10.3390/life13071459 - 27 Jun 2023
Cited by 1 | Viewed by 2222
Abstract
Neonatal apnoea can be treated with caffeine, which affects the central nervous and cardiovascular systems. Heart rate variability (HRV) reflects the activity of the autonomic nervous system (ANS) and might be used as a measure of ANS maturation in newborns. We aimed to [...] Read more.
Neonatal apnoea can be treated with caffeine, which affects the central nervous and cardiovascular systems. Heart rate variability (HRV) reflects the activity of the autonomic nervous system (ANS) and might be used as a measure of ANS maturation in newborns. We aimed to establish the effect of caffeine on HRV in newborns and investigated the potential correlation between HRV and postmenstrual age (PMA). In 25 haemodynamically stable newborns hospitalized due to apnoea and treated with caffeine (2.5 mg/kg), we assessed breathing frequency, arterial oxygen saturation, body temperature, and the heart rate while they were sleeping. We assessed HRV by spectral analysis using fast Fourier transformation. The same protocol was reapplied 100 h after caffeine withdrawal to assess the control parameters. Caffeine increased breathing frequency (p = 0.023) but did not affect any other parameter assessed including HRV. We established a positive correlation between postmenstrual age and HRV during treatment with caffeine as well as after caffeine had been withdrawn (total power: p = 0.044; low-frequency band: p = 0.039). Apparently, the maintenance dose of caffeine is too low to affect the heart rate and HRV. A positive correlation between PMA and HRV might reflect maturation of the ANS, irrespective of caffeine treatment. Full article
(This article belongs to the Special Issue New Insights into Cardiovascular and Exercise Physiology)
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17 pages, 2449 KiB  
Article
Effects of Home-Based Exercise Training on Cardiac Autonomic Neuropathy and Metabolic Profile in Diabetic Hemodialysis Patients
by Vassiliki Michou, Vassilios Liakopoulos, Stefanos Roumeliotis, Athanasios Roumeliotis, Maria Anifanti, Georgios Tsamos, Aikaterini Papagianni, Pantelis Zempekakis, Asterios Deligiannis and Evangelia Kouidi
Life 2023, 13(1), 232; https://doi.org/10.3390/life13010232 - 13 Jan 2023
Cited by 7 | Viewed by 2638
Abstract
Background: This study aimed to investigate the effects of a home-based exercise training program on Cardiac Autonomic Neuropathy (CAN) and metabolic profile in Diabetic Kidney Disease (DKD) patients undergoing maintenance hemodialysis (HD). Method: Twenty-eight DKD patients undergoing hemodialysis were randomly assigned into two [...] Read more.
Background: This study aimed to investigate the effects of a home-based exercise training program on Cardiac Autonomic Neuropathy (CAN) and metabolic profile in Diabetic Kidney Disease (DKD) patients undergoing maintenance hemodialysis (HD). Method: Twenty-eight DKD patients undergoing hemodialysis were randomly assigned into two groups. The exercise (EX) group followed a 6-month combined exercise training program at home, while the control (CO) group remained untrained. All participants at baseline and the end of the study underwent cardiopulmonary exercise testing (CPET), biochemical tests for glucose and lipid profile, and 24-h electrocardiographic monitoring for heart rate variability (HRV) analysis and heart rate turbulence (HRT). Results: At the end of the study, compared to the CO, the EX group showed a significant increase in serum high-density lipoprotein (HDL) by 27.7% (p = 0.01), peak oxygen uptake (VO2peak) by 9.3% (p < 0.05), the standard deviation of R-R intervals (SDNN) by 34.3% (p = 0.03), percentage of successive RR intervals higher than 50ms (pNN50) by 51.1% (p = 0.02), turbulence slope (TS) index by 18.4% (p = 0.01), and decrease in (glycated hemoglobin) HbA1c by 12.5% (p = 0.04) and low-frequency power LF (ms2) by 29.7% (p = 0.01). Linear regression analysis after training showed that VO2peak was correlated with SDNN (r = 0.55, p = 0.03) and HF (r = 0.72, p = 0.02). Multiple regression analysis indicated that the improvement of sympathovagal balance and aerobic capacity depended on patients’ participation in exercise training. Conclusion: In conclusion, a 6-month home-based mixed-type exercise program can improve cardiac autonomic function and metabolic profile in DKD patients on HD. Full article
(This article belongs to the Special Issue New Insights into Cardiovascular and Exercise Physiology)
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14 pages, 6844 KiB  
Article
Assessment of Countermovement Jump: What Should We Report?
by Zdravko Anicic, Danica Janicijevic, Olivera M. Knezevic, Amador Garcia-Ramos, Milos R. Petrovic, Dimitrije Cabarkapa and Dragan M. Mirkov
Life 2023, 13(1), 190; https://doi.org/10.3390/life13010190 - 9 Jan 2023
Cited by 39 | Viewed by 11464
Abstract
The purpose of the present study was (i) to explore the reliability of the most commonly used countermovement jump (CMJ) metrics, and (ii) to reduce a large pool of metrics with acceptable levels of reliability via principal component analysis to the significant factors [...] Read more.
The purpose of the present study was (i) to explore the reliability of the most commonly used countermovement jump (CMJ) metrics, and (ii) to reduce a large pool of metrics with acceptable levels of reliability via principal component analysis to the significant factors capable of providing distinctive aspects of CMJ performance. Seventy-nine physically active participants (thirty-seven females and forty-two males) performed three maximal CMJs while standing on a force platform. Each participant visited the laboratory on two occasions, separated by 24–48 h. The most reliable variables were performance variables (CV = 4.2–11.1%), followed by kinetic variables (CV = 1.6–93.4%), and finally kinematic variables (CV = 1.9–37.4%). From the 45 CMJ computed metrics, only 24 demonstrated acceptable levels of reliability (CV ≤ 10%). These variables were included in the principal component analysis and loaded a total of four factors, explaining 91% of the CMJ variance: performance component (variables responsible for overall jump performance), eccentric component (variables related to the breaking phase), concentric component (variables related to the upward phase), and jump strategy component (variables influencing the jumping style). Overall, the findings revealed important implications for sports scientists and practitioners regarding the CMJ-derived metrics that should be considered to gain a comprehensive insight into the biomechanical parameters related to CMJ performance. Full article
(This article belongs to the Special Issue New Insights into Cardiovascular and Exercise Physiology)
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11 pages, 981 KiB  
Article
Prediction of Maximal Oxygen Consumption in Cycle Ergometry in Competitive Cyclists
by Iva Jurov, Janez Toplišek and Marta Cvijić
Life 2023, 13(1), 160; https://doi.org/10.3390/life13010160 - 5 Jan 2023
Cited by 2 | Viewed by 2196
Abstract
Models for predicting maximal oxygen consumption (VO2max) in average adults might not be suitable for athletes, especially for competitive cyclists who can have significantly higher VO2max than normally active people. The aim of this study was to develop a clinically [...] Read more.
Models for predicting maximal oxygen consumption (VO2max) in average adults might not be suitable for athletes, especially for competitive cyclists who can have significantly higher VO2max than normally active people. The aim of this study was to develop a clinically applicable equation for predicting VO2max during cycle ergometry in competitive cyclists and to compare its accuracy to the traditional American College of Sports Medicine (ACSM) equation. Maximal cycle ergometry tests were performed in 496 male and 84 female competitive cyclists. Six predictors were initially used to model the prediction equation (power output, body weight, body height, fat mass, fat-free mass and age). Power output and body weight were the most important parameters in the model predicting VO2max. Three new equations were derived: for male (VO2max = 0.10 × PO − 0.60 × BW + 64.21), female cyclists (0.13 × PO − 0.83 × BW + 64.02) and the non-gender-specific formula (0.12 × PO − 0.65 × BW + 59.78). The ACSM underestimated VO2max in men by 7.32 mL/min/kg (11.54%), in women by 8.24 mL/min/kg (15.04%) and in all participants by 7.45 mL/min/kg (11.99%), compared to the new equation that underestimated VO2max in men by 0.12 mL/min/kg (0.19%) and in all participants by 0.65 mL/min/kg (1.04%). In female cyclists, the new equation had no relative bias. We recommend that medicine and sports practitioners adapt our proposed equations when working with competitive cyclists. Our findings demonstrate the need to evaluate prediction models for other athletes with a special focus on disciplines that demand high aerobic capacity. Full article
(This article belongs to the Special Issue New Insights into Cardiovascular and Exercise Physiology)
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13 pages, 538 KiB  
Article
The Energetic Costs of Uphill Locomotion in Trail Running: Physiological Consequences Due to Uphill Locomotion Pattern—A Feasibility Study
by Paul Zimmermann, Nico Müller, Volker Schöffl, Benedikt Ehrlich, Othmar Moser and Isabelle Schöffl
Life 2022, 12(12), 2070; https://doi.org/10.3390/life12122070 - 9 Dec 2022
Cited by 2 | Viewed by 2165
Abstract
The primary aim of our feasibility reporting was to define physiological differences in trail running (TR) athletes due to different uphill locomotion patterns, uphill running versus uphill walking. In this context, a feasibility analysis of TR athletes’ cardiopulmonary exercise testing (CPET) data, which [...] Read more.
The primary aim of our feasibility reporting was to define physiological differences in trail running (TR) athletes due to different uphill locomotion patterns, uphill running versus uphill walking. In this context, a feasibility analysis of TR athletes’ cardiopulmonary exercise testing (CPET) data, which were obtained in summer 2020 at the accompanying sports medicine performance center, was performed. Fourteen TR athletes (n = 14, male = 10, female = 4, age: 36.8 ± 8.0 years) were evaluated for specific physiological demands by outdoor CPET during a short uphill TR performance. The obtained data of the participating TR athletes were compared for anthropometric data, CPET parameters, such as V˙Emaximum, V˙O2maximum, maximal breath frequency (BFmax) and peak oxygen pulse as well as energetic demands, i.e., the energy cost of running (Cr). All participating TR athletes showed excellent performance data, whereby across both different uphill locomotion strategies, significant differences were solely revealed for V˙Emaximum (p = 0.033) and time to reach mountain peak (p = 0.008). These results provide new insights and might contribute to a comprehensive understanding of cardiorespiratory consequences to short uphill locomotion strategy in TR athletes and might strengthen further scientific research in this field. Full article
(This article belongs to the Special Issue New Insights into Cardiovascular and Exercise Physiology)
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Review

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13 pages, 5637 KiB  
Review
Role of Exercise Stress Echocardiography in Pulmonary Hypertension
by Mojca Škafar, Jana Ambrožič, Janez Toplišek and Marta Cvijić
Life 2023, 13(6), 1385; https://doi.org/10.3390/life13061385 - 14 Jun 2023
Viewed by 2199
Abstract
Resting and exercise right heart catheterisation is the gold standard method to diagnose and differentiate types of pulmonary hypertension (PH). As it carries technical challenges, the question arises if non-invasive exercise stress echocardiography may be used as an alternative. Exercise echocardiography can unmask [...] Read more.
Resting and exercise right heart catheterisation is the gold standard method to diagnose and differentiate types of pulmonary hypertension (PH). As it carries technical challenges, the question arises if non-invasive exercise stress echocardiography may be used as an alternative. Exercise echocardiography can unmask exercise PH, detect the early stages of left ventricular diastolic dysfunction, and, therefore, differentiate between pre- and post-capillary PH. Regardless of the underlying aetiology, a developed PH is associated with increased mortality. Parameters of overt right ventricle (RV) dysfunction, including RV dilation, reduced RV ejection fraction, and elevated right-sided filling pressures, are detectable with resting echocardiography and are associated with worse outcome. However, these measures all fail to identify occult RV dysfunction. Echocardiographic measures of RV contractile reserve during exercise echocardiography are very promising and provide incremental prognostic information on clinical outcome. In this paper, we review pulmonary haemodynamic response to exercise, briefly describe the modalities for assessing pulmonary haemodynamics, and discuss in depth the contemporary key clinical application of exercise stress echocardiography in patients with PH. Full article
(This article belongs to the Special Issue New Insights into Cardiovascular and Exercise Physiology)
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18 pages, 2775 KiB  
Review
A Meta-Analysis of Sampled Maximal Aerobic Capacity Data for Boys Aged 11 Years Old or Less Obtained by Cycle Ergometry
by Iva Jurov, Jure Demšar and Thomas McCurdy
Life 2023, 13(2), 276; https://doi.org/10.3390/life13020276 - 19 Jan 2023
Cited by 1 | Viewed by 1552
Abstract
The aim of this study was to develop distributions of VO2max based on measured values that exist in the literature in prepubertal boys using cycle ergometry. PRISMA guidelines were followed in conducting this research. One database was searched for peak and maximal [...] Read more.
The aim of this study was to develop distributions of VO2max based on measured values that exist in the literature in prepubertal boys using cycle ergometry. PRISMA guidelines were followed in conducting this research. One database was searched for peak and maximal VO2 values in healthy boys with mean age under 11 years old. Data were split into articles reporting absolute and relative VO2max values and analyzed accordingly. Multilevel models grounded in Bayesian principles were used. We investigated associations between VO2max and body mass, year of the study, and country of origin. Differences in “peak” and “maximal” VO2 were assessed. Absolute VO2max (Lmin−1) increases with age (P ~100%) but mean relative VO2max does not change (P ~100%). Absolute VO2max is higher in more recent studies (P = 95.7 ± 0.3%) and mean relative VO2max is lower (P = 99.6 ± 0.1%). Relative VO2max in the USA is lower compared with boys from other countries (P = 98.8 ± 0.2%), but there are no differences in absolute values. Mean aerobic capacity estimates presented as “peak” values are higher than “maximal” values on an absolute basis (P = 97.5 ± 0.3%) but not on a relative basis (P = 99.6 ± 0.1%). Heavier boys have lower cardiorespiratory fitness (P ≈ 100%), and body mass seems to be increasing faster with age in the USA compared with other countries (P = 92.3 ± 0.3%). New reference values for cardiorespiratory fitness are presented for prepubertal boys obtained with cycle ergometry. This is new, as no reference values have been determined so far based on actual measured values in prepubertal boys. Aerobic capacity normalized to body weight does not change with age. Cardiorespiratory fitness in prepubertal boys is declining, which is associated with increasing body mass over the last few decades. Lastly, this study did not find any statistically significant difference in the sample’s mean aerobic capacity estimates using the ”peak” and “maximum” distinctions identified in the literature. Full article
(This article belongs to the Special Issue New Insights into Cardiovascular and Exercise Physiology)
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Other

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15 pages, 3178 KiB  
Case Report
Recovery after Running an “Everesting” Mountain Ultramarathon
by Anton Ušaj, Jon Lihteneger Vidmajer and Sonja Lojen
Life 2023, 13(10), 1946; https://doi.org/10.3390/life13101946 - 22 Sep 2023
Viewed by 1225
Abstract
Blood markers of muscle microdamage and systemic inflammation do not adequately explain the reduced performance observed over a prolonged recovery after running a mountain ultramarathon. This case study aimed to determine whether the reduced performance after the Everesting mountain ultramarathon can be further [...] Read more.
Blood markers of muscle microdamage and systemic inflammation do not adequately explain the reduced performance observed over a prolonged recovery after running a mountain ultramarathon. This case study aimed to determine whether the reduced performance after the Everesting mountain ultramarathon can be further assessed by considering cardiorespiratory and metabolic alterations determined via repeated incremental and continuous running tests. A single runner (age: 24 years, BM: 70 kg, BMI: 22, Vo2peak: 74 mL∙min−1∙kg−1) was observed over a preparatory period of two months with a one-month recovery period. The Everesting consisted of nine ascents and descents of 9349 vertical metres completed in 18:22 (h:min). During the first phase of the recovery, enhanced peak creatine kinase (800%) and C-reactive protein (44%) levels explained the decreased performance. In contrast, decreased performance during the second, longer phase was associated with a decreased lactate threshold and Vo2 (21% and 17%, respectively), as well as an increased energetic cost of running (15%) and higher endogenous carbohydrate oxidation rates (87%), lactate concentrations (170%) and respiratory muscle fatigue sensations that remained elevated for up to one month. These alterations may represent characteristics that can explain the second phase of the recovery process after Everesting. Full article
(This article belongs to the Special Issue New Insights into Cardiovascular and Exercise Physiology)
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12 pages, 7989 KiB  
Case Report
Takotsubo Cardiomyopathy Occurring Simultaneously with Acute Myocardial Infarction
by Ilija Srdanović, Dragana Dabović, Vladimir Ivanović, Milenko Čanković, Teodora Pantić, Maja Stefanović, Sonja Dimić, Branislav Crnomarković, Marija Bjelobrk, Miljana Govedarica and Marija Zdravković
Life 2023, 13(8), 1770; https://doi.org/10.3390/life13081770 - 18 Aug 2023
Viewed by 1195
Abstract
Introduction: Takotsubo cardiomyopathy (TCM) is a reversible form of cardiomyopathy characterized by transient regional systolic dysfunction of the left ventricle. Case outline: A 78-year-old woman was admitted to the general hospital due to acute inferior STEMI late presentation. Two days after admission, the [...] Read more.
Introduction: Takotsubo cardiomyopathy (TCM) is a reversible form of cardiomyopathy characterized by transient regional systolic dysfunction of the left ventricle. Case outline: A 78-year-old woman was admitted to the general hospital due to acute inferior STEMI late presentation. Two days after admission, the patient reported intense chest pain and an ECG registered diffuse ST-segment elevation in all leads with ST-segment denivelation in aVR. The patient also showed clinical signs of cardiogenic shock and was referred to a reference institution for further evaluation. Echocardiography revealed akinesia of all medioapical segments, dynamic obstruction of the left ventricular outflow tract (LVOT), moderate mitral regurgitation, and pericardial effusion. Coronary angiography showed the suboccluded right coronary artery, and a primary percutaneous coronary intervention was performed, which involved implanting a drug-eluting stent. The patient’s condition worsened as pericardial effusion increased and led to tamponade. Pericardiocentesis was performed, resulting in the patient’s stabilization. At this point, significant gradients at the LVOT and pericardial effusion were not registered. After eight days without symptoms and stable status, the patient was discharged. Conclusions: The simultaneous presence of AMI and TCM increases the risk of developing cardiogenic shock. The cardio-circulatory profile of these patients is different from those with AMI. Full article
(This article belongs to the Special Issue New Insights into Cardiovascular and Exercise Physiology)
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