Myocardial Injury and Ventricular Dysfunction Related to Training Levels Among Nonelite Participants in the Boston Marathon

Emergency Point-of-Care Blood Gas Analysis During Mass Gathering Events: Experiences of the Vienna City Marathon

Background: Long-distance running impacts many organ systems. Aside from musculoskeletal and cardiopulmonary events, the gastrointestinal and renal system as well as metabolic homeostasis and electrolyte balance can be affected. A respective medical support strategy enabling rapid diagnosis, triage, and treatment in the context of large sports events is thus of utmost importance. Incidents can be assessed and graded via point-of-care (POC) blood gas analysis (BGA). We thus aimed to evaluate the feasibility and benefits of its use during a large sports event. Methods: All documented patient contacts during the race of the Vienna City Marathon (VCM) 2023 were retrospectively assessed. Additionally, the BGAs conducted in all patients requiring intravenous access were analyzed. Data are presented in a descriptive manner. Results: There were 39,871 participants at the VCM 2023. Of these, 277 (0.7%) required medical support, localized most commonly in the finishing area of the race (n = 239, 86% of all incidents). Fifty-eight (20.9%) patients had to be hospitalized. The most frequent chief complaints were syncope or collapse (24.9%), followed by general pain (20.6%) and trauma (14.8%). Five patients (1.8%) suffered from seizures, and one experienced (0.4%) from spontaneous pneumothorax. Thirty-one patients (11.2%) received venous blood gas analyses, showing mean creatinine levels of 1.82 (±0.517) mg/dL, mean lactate concentrations of 6.03 (±4.5) mmol/L, mean pH of 7.42 (±0.0721), and a mean base excess of -0.72 (±3.72) mmol/L. No cases of hyponatremia occurred in the documented samples. In eight cases (25.8%), sodium concentrations were above 145 mmol/L, with a maximum of 149 mmol/L. No cardiac arrests occurred. Conclusions: The physical exertion during the assessed long-distance running race resulted in numerous contacts with the medical support teams. The use of POC BGA at a large-scale marathon event was shown to be easy and feasible, allowing for more extensive diagnostics on-site. It can be integrated into a medical support strategy and might be beneficial for decision-making regarding patient triage, treatment, hospitalization, or patient discharge.

Are Subjective Reports of Exercise Intensity Accurate in Recreational Athletes?

BACKGROUND

Quantifying exercise intensity accurately is crucial for understanding links between cumulative exercise and cardiovascular outcomes. Exercise burden, the integral of intensity and duration is often estimated from subjective self-reports which have uncertain accuracy.

METHODS

We studied 40 endurance athletes (EAs) 41 to 69 years of age with > 10 years of training history during a scripted outdoor 42-km cycling training session. Heart rate and power output (watts) were continuously measured. Reports of perceived exertion (RPE) using a word (RPEWord) and numerical Borg scale (RPEBorg) were obtained during and 30 minutes postride and were related to cardiac (heart rate) and metabolic (metabolic equivalent [MET] per minute) exercise endpoints.

RESULTS

RPEs were highly variable, underestimating objective metrics of exercise intensity. Poor agreement was observed between either scale reported 30 minutes after exercise relative to heart rate: exercise RPEBorg vs mean exercise heart rate and % heart ratepeak (both rs = 0.29; P = 0.07), with no agreement between either scale vs other objective endpoints. Agreement between RPEBorg and RPEWord was good during exercise (rs = 0.86; 95% confidence interval (CI), 0.75- 0.92; P = 0.001), but diminished postride (rs = 0.54; 95% CI, 0.28-0.73; P = 0.001). Different cardiac and metabolic profiles during exercise and a contrast between metabolic and cardiac burden was greater in less fit individuals as they accrued greater cardiac (14,039 ± 2649 vs 11,784 ± 1132 heart rate per minute; P < 0.01) but lower metabolic (808 ± 59 vs 858 ± 61 MET per minute; P < 0.05) burden vs fitter EA.

CONCLUSIONS

Caution is advised in interpreting MET per minute and heart rate burden estimated from self-reports. Objective measurements of exercise intensity are required for detailed assessment of the risks and benefits of long-term exercise.

Physiology and Pathophysiology of Marathon Running: A narrative Review

BACKGROUND

Marathon training and running have many beneficial effects on human health and physical fitness; however, they also pose risks. To date, no comprehensive review regarding both the benefits and risks of marathon running on different organ systems has been published.

MAIN BODY

The aim of this review was to provide a comprehensive review of the benefits and risks of marathon training and racing on different organ systems. A predefined search strategy including keywords (e.g., marathon, cardiovascular system, etc.) and free text search was used. Articles covering running regardless of sex, age, performance level, and event type (e.g., road races, mountain marathons) were considered, whereas articles examining only cycling, triathlon, stress-tests or other sports were excluded. In total, we found 1021 articles in PubMed, Scopus, and Google Scholar, of which 329 studies were included in this review. Overall, marathon training offers several benefits for different organ systems and reduces all-cause mortality. As such, it improves cardiovascular risk factors, leads to favorable cardiac adaptations, enhances lung function, and improves quality of life in chronic kidney disease patients. It also enhances gastrointestinal mobility and reduces the risk of specific tumors such as colorectal cancer and hepatocellular carcinoma. Marathon training enhances bone health and skeletal muscle metabolism. It further positively affects hematopoiesis and cytotoxic abilities of natural killer cells, and may act neuroprotective on a long-term basis. After a marathon, changes in biomarkers suggesting pathological events in certain organ systems such as cardiovascular, renal, gastrointestinal, liver, hematological, immune, musculoskeletal, central nervous, and endocrine systems can often be observed. Mostly, these changes are limited to 1-3 days post-race and usually normalize within a week. Moreover, marathon running poses the risk of serious adverse events such as sudden cardiac death or acute liver failure. Concerning lung function, a decrease after a marathon race was observed. Acute kidney injury, as well as electrolyte imbalances, are relatively common amongst marathon finishers. Many runners complain of gastrointestinal symptoms during or after long-distance running. Many runners suffer from running-related musculoskeletal injuries often impairing performance. A marathon is often accompanied by an acute inflammatory response with transient immunosuppression, making runners susceptible to infections. Also, hormonal alterations such as increased cortisol levels or decreased testosterone levels immediately after a race are observed. Disturbances in sleep patterns are commonly found in marathon runners leading up to or directly after the race.

CONCLUSION

All in all, marathon training is generally safe for human health and individual organ systems. Considering the high popularity of marathon running, these findings supply athletes, coaches, sports scientists, and sports medicine practitioners with practical applications. Further large-scale studies examining long-term effects on the cardiovascular, renal, and other system are needed.

Olympic distance duathlon and cardiac performance in highly-trained triathletes

The effects of triathlon exercise on cardiac function are well documented. While Olympic triathlon (swim-bike-run) remains the standard format, increasing concerns about water quality in natural waterways present ongoing challenges for open-water swimming events, highlighting the potential need to consider alternative formats such as duathlon (run-bike-run) in some circumstances. An additional run may increase the overall metabolic and cardiovascular demand compared with the swim in triathlon, leading to reduced future performance. Conversely, the majority of EICF research reports reversal of post-exercise perturbations within 24-7 days of recovery but duathlon has not yet been studied in this context. Therefore, this study aimed to investigate the cardiac, autonomic, haemodynamic and biomarker responses during and following two Olympic distance (OD) duathlon separated by 7 days of recovery. Highly-trained (V O2max >60 mL·kg-1·min-1) male participants (n = 10) completed two lab-based OD duathlons, either continuous (BD) or with functional measurements after each leg (UD), separated by 7 days of rest. Conventional echocardiography recorded standard and tissue Doppler measures of left ventricular (LV) structure and function. Speckle tracking echocardiography was used to measure global longitudinal strain (GLS). Time and frequency domain analysis of HRV, as well as plasma high sensitivity cardiac troponin T (hs-cTnT) were measured pre and post exercise. In the broken duathlon trial (BD) cardiac measurements and blood samples were also taken between each leg. In the unbroken duathlon (UD) participants performed each leg sequentially. Duathlon exercise resulted in similar cardiac functional and biomarker alterations as previously reported in triathlon and standalone running and cycling exercise. Cardiac troponins were still elevated following 24 h-1 of recovery. However, functional changes were resolved within 24 h-1 of passive recovery and did not impair subsequent duathlon performance, or pre-exercise measurements 7 days after the first trial. Whether or not elite or recreational athletes experience the same magnitude and reversibility of these changes remains to be elucidated further.

Diastolic function and dysfunction in athletes

Cardiac remodelling is often most profound in male athletes and in athletes with the greatest volumes of endurance training and is characterized by chamber enlargement and a mild-to-modest hypertrophy. The diastolic filling of the left ventricle (LV) is a complex process including the early recoil of the contracted LV, the active relaxation of the myocardium, the compliance of the myocardium, the filling pressures, and heart rate. Echocardiography is the cornerstone for the clinical assessment of LV diastolic function. LV diastolic function is usually enhanced in elite endurance athletes characterized by improved early filling of the ventricle, while it is preserved or enhanced in other athletes associated with the type of training being performed. This allows for the high performance of any endurance athlete. Typical findings when using resting echocardiography for the assessment of LV diastolic function in endurance athletes include a dilated LV with normal or mildly reduced LV ejection fraction (EF), significantly enlarged left atrium (LA) beyond the commonly used cut-off of 34 mL/m2, and a significantly elevated E/A ratio. The early-diastolic mitral annular velocity and the E-wave peak velocity are usually normal. Importantly, interpretation of the echocardiographic indices of LV diastolic function should always consider the clinical context and other parameters of systolic and diastolic functions. In the absence of an underlying pathology, single measurements outside the expected range for similar athletes will often not represent the pathology.

Exercise-Induced Cardiac Troponin I Elevation Is Associated With Regional Alterations in Left Ventricular Strain in High-Troponin Responders

BACKGROUND

The implications of exercise-induced cardiac troponin elevation in healthy individuals are unclear. This study aimed to determine if individuals with a high exercise-induced cardiac troponin I (cTnI) response have alterations in myocardial function following high-intensity endurance exercise compared with normal-cTnI responders.

METHODS AND RESULTS

Study individuals were recruited from previous participants in a 91-km mountain bike cycling race (the North Sea Race) and were classified as high- (n=34) or normal-cTnI responders (n=25) based on maximal cTnI values after the recruitment race. The present study exposed all participants to 2 prolonged high-intensity exercises: a combined lactate threshold and cardiopulmonary exercise test and repeated participation in the North Sea Race. Echocardiography was performed before, immediately after, and 24 hours following exercise. All study individuals (n=59) had normal coronary arteries, and were aged 51±10 years; 46 (74%) were men. There were no differences in baseline characteristics between the high- and normal-cTnI responders. Maximal cTnI levels 3 hours after exercise were significantly higher in the high- compared with normal-cTnI group (P<0.001-0.027). Following exercise, there were no differences in global ventricular function between the 2 groups. In contrast, high-cTnI responders had significantly lower regional strain in the anteroseptal segments following exercise, with more profound changes after the race.

CONCLUSIONS

High-cTnI responders had lower anteroseptal segmental strain shortly after exercise than normal-cTnI responders. However, there were no permanent alterations in myocardial strain, indicating no short- or long-term adverse consequences of these exercise-induced alterations in myocardial function.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02166216.

Acute effect of ultramarathon on systolic and diastolic cardiac function: Systematic review and meta-analysis

BACKGROUND

Ultramarathon running poses physiological challenges, impacting cardiac function. This systematic review and meta-analysis explore the acute effects of single-stage ultramarathon running on cardiac function.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations were followed. Searches covered Medline, Embase, CINAHL, SPORTDiscus, Web of Science, Central Cochrane, and Scopus. Random effects meta-analyses assessed left ventricular (LV) and right ventricular (RV) variables, expressed as mean differences (MD) with 95% confidence intervals (CI).

RESULTS

Among 6972 studies, 17 were included. Post-ultramarathon reductions were found in LV end-diastolic diameter (LVEDD) (-1.24; 95% CI = -1.77, -0.71 mm), LV end-diastolic volume (LVEDV) (-9.92; 95% CI = -15.25, -4.60 ml), LV stroke volume (LVSV) (-8.96 ml, 95% CI -13.20, -4.72 ml), LV ejection fraction (LVEF) (-3.71; 95% CI = -5.21, -2.22%), LV global longitudinal strain (LVGLS) (-1.48; 95% CI = -2.21, -0.76%), E/A (-0.30; 95% CI = -0.38, -0.22 cm/s), .E' (-1.35 cm/s, 95% CI -1.91, -0.79 cm/s), RV fractional area change (RVFAC) (-3.34, 95% CI = -5.84, -0.84%), tricuspid annular plane systolic excursion (TAPSE) (-0.12, 95% CI = -0.22, -0.02 cm), RV global longitudinal strain (RVGLS) (-1.73, 95% CI = -2.87, -0.59%), with increases in RV end-diastolic area (RVEDA) (1.89, 95% CI = 0.63, 3.14 cm2), RV Peak A' (1.32 cm/s, 95% CI 0.20, 2.44), and heart rate (18.24, 95% CI = 15.16, 21.32). No significant differences were observed in LV end-systolic diameter (LVESD), LV end-systolic volume (LVESV), RV end-diastolic diameter (RVEDD), RV Peak E', and RV Peak S'.

CONCLUSIONS

Evidence suggests immediate impairment of systolic and diastolic cardiac function post-ultramarathon running.

Exercise-induced cardiac troponin elevations and cardiac ventricular dysfunction assessed by tissue Doppler echocardiography and speckle tracking among non-elite runners in Beijing marathon

OBJECTIVES

We aimed to identify the major determinants of cardiac troponin changes response to exercise among non-elite runners participating in the Beijing 2022 marathon, with a particular focus on the associations with the cardiac function assessed by tissue Doppler echocardiography and speckle tracking.

DESIGN

A prospective study.

METHODS

A total of 33 non-elite participants in the 2022 Beijing Marathon were included in the study. Echocardiographic assessment and blood sample collection were conducted before, immediately after, and two weeks after the marathon. Blood samples were analyzed using the same Abbot high-sensitivity cTnI STAT assay. Echocardiography included tissue Doppler and speckle tracking echocardiography.

RESULTS

Following the marathon, significant increases were observed in cardiac biomarkers, with hs-cTnI elevating from 3.1 [2.3-6.7] to 49.6 [32.5-76.9] ng/L (P < 0.0001). Over 72 % of participants had post-race hs-TnI levels surpassing the 99th percentile upper reference limit. There was a notable correlation between pre-marathon hs-cTnI levels (β coefficient, 0.56 [0.05, 1.07]; P = 0.042), weekly average training (β coefficient, -1.15 [-1.95, -0.35]; P = 0.009), and hs-cTnI rise post-marathon. Echocardiography revealed significant post-race cardiac function changes, including decreased E/A ratio (P < 0.0001), GWI (P < 0.0001), and GCW (P < 0.0001), with LVEF (β coefficients, 0.112 [0.01, 0.21]; P = 0.042) and RV GLS (β coefficients, 0.124 [0.01, 0.23]; P = 0.035) changes significantly associated with hs-TnI alterations. All echocardiographic and laboratory indicators reverted to baseline levels within two weeks.

CONCLUSIONS

Baseline hs-cTnI levels and weekly average training influence exercise-induced hs-cTnI elevation in non-elite runners. Echocardiography revealed post-race changes in cardiac function, with LVEF and RV GLS significantly associated with hs-TnI alterations. These findings contribute to understanding the cardiac response to exercise and could guide training and recovery strategies.

Cardiac biomarker responses following high-intensity interval and continuous exercise: the influence of ACE-I/D gene polymorphism and training status in men

This study aimed to investigate the relationship between pre- and postexercise cardiac biomarker release according to athletic status (trained vs. untrained) and to establish whether the I/D polymorphism in the angiotensin-converting enzyme (ACE) gene had an influence on cardiac biomarkers release with specific regard on the influence of the training state. We determined cardiac troponin I (cTnI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in 29 trained and 27 untrained male soccer players before and after moderate-intensity continuous exercise (MICE) and high-intensity interval exercise (HIIE) running tests. Trained soccer players had higher pre (trained: 0.014 ± 0.007 ng/mL; untrained: 0.010 ± 0.005 ng/mL) and post HIIE (trained: 0.031 ± 0.008 ng/mL; untrained: 0.0179 ± 0.007) and MICE (trained: 0.030 ± 0.007 ng/mL; untrained: 0.018 ± 0.007) cTnI values than untrained subjects, but the change with exercise (ΔcTnI) was similar between groups. There was no significant difference in baseline and postexercise NT-proBNP between groups. NT-proBNP levels were elevated after both HIIE and MICE. Considering three ACE genotypes, the mean pre exercise cTnI values of the trained group (DD: 0.015 ± 0.008 ng/mL, ID: 0.015 ± 0.007 ng/mL, and II: 0.014 ± 0.008 ng/mL) and their untrained counterparts (DD: 0.010 ± 0.004 ng/mL, ID: 0.011 ± 0.004 ng/mL, and II: 0.010 ± 0.006 ng/mL) did not show any significant difference. To sum up, noticeable difference in baseline cTnI was observed, which was related to athletic status but not ACE genotypes. Neither athletic status nor ACE genotypes seemed to affect the changes in cardiac biomarkers in response to HIIE and MICE, indicating that the ACE gene does not play a significant role in the release of exercise-induced cardiac biomarkers indicative of cardiac damage in Iranian soccer players.NEW & NOTEWORTHY Our study investigated the impact of athletic status and angiotensin-converting enzyme (ACE) gene I/D polymorphism on cardiac biomarkers in soccer players. Trained players showed higher baseline cardiac troponin I (cTnI) levels, whereas postexercise ΔcTnI remained consistent across groups. N-terminal pro-brain natriuretic peptide increased after exercise in both groups, staying within normal limits. ACE genotypes did not significantly affect pre-exercise cTnI. Overall, athletic status influences baseline cTnI, but neither it nor ACE genotypes significantly impact exercise-induced cardiac biomarker responses in this population.

Themes and trends in marathon performance research: a comprehensive bibliometric analysis from 2009 to 2023

Background: When marathon runners break the 2-h barrier at the finishing line, it attracts global attention. This study is aimed to conduct a bibliometric analysis of publications in the field of marathon running, analyze relevant research contributors, and visualize the historical trends of marathon performance research over the past 15 years. Methods: On 8 December 2023, we extracted high-quality publication data from the Web of Science Core Collection spanning from 1 January 2009 to 30 November 2023. We conducted bibliometric analysis and research history visualization using the R language packages biblioshiny, VOSviewer, and CiteSpace. Results: A total of 1,057 studies were published by 3,947 authors from 1,566 institutions across 63 countries/regions. USA has the highest publication and citation volume, while, the University of Zurich being the most prolific research institution. Keywords analysis revealed several hotspots in marathon research over the past 3 years: (1) physiology of the elite marathon runners, (2) elite marathon training intensity and pacing strategies, (3) nutritional strategies for elite marathon runners, (4) age and sex differences in marathon performance, (5) recovery of inflammatory response and muscle damage. Conclusion: This study presents the first comprehensive bibliometric analysis of marathon performance research over the past 15 years. It unveils the key contributors to marathon performance research, visually represents the historical developments in the field, and highlights the recent topical frontiers. The findings of this study will guide future research by identifying potential hotspots and frontiers.

The current paradigm of cardiac troponin increase among athletes

Although it is known that exercise improves cardiovascular health and extends life expectancy, a significant number of people may also experience an elevation in cardiac troponin levels as a result of exercise. For many years, researchers have argued whether exercise-induced cardiac troponin rises are a consequence of a physiological or pathological reaction and whether they are clinically significant. Differences in cardiac troponin elevation and cardiac remodeling can be seen between athletes participating in different types of sports. When forecasting the exercise-induced cardiac troponin rise, there are many additional parameters to consider, as there is a large amount of interindividual heterogeneity in the degree of cardiac troponin elevation. Although it was previously believed that cardiac troponin increases in athletes represented a benign phenomenon, numerous recent studies disproved this notion by demonstrating that, in specific individuals, cardiac troponin increases may have clinical and prognostic repercussions. This review aims to examine the role of cardiac troponin in athletes and its role in various sporting contexts. This review also discusses potential prognostic and clinical implications, as well as future research methods, and provides a straightforward step-by-step algorithm to help clinicians interpret cardiac troponin rise in athletes in both ischemic and non-ischemic circumstances.

Exercise-Induced Troponin Elevation in High-Performance Cross-Country Skiers

Background: Troponin I and T are biomarkers to diagnose myocardial infarction and damage. Studies indicate that strenuous physical activity can cause transient increases in these troponin levels, typically considered physiological. However, current data show differences in the exercise-induced increase in troponin I and T in elite athletes. Method: This prospective clinical study aimed to determine troponin I and T levels in 36 top cross-country skiers of the German national team (18 male, 18 female) after a standardized competition load over two days. All study participants underwent a comprehensive sports medical and cardiological evaluation, including ECG and echocardiography. A multivariable regression analysis was utilized to identify possible predictors of increased troponin I levels. Results: Only three male athletes (8.1%) showed an isolated increase in Troponin I (Ø 112.49 ng/L, cut off < 45.2 ng/L), while no increase in troponin T in the study population was detected. Conclusions: The analysis suggested several potential predictors for increased troponin I levels, such as height, weight, weekly training hours, and indications of an enlarged sports heart, though none achieved statistical significance. Knowing the different exercise-induced detectability of the various troponins in the clinical setting is essential.

Cardiovascular risk of veterans' football: An observational cohort study with follow-up

BACKGROUND

The cardiac stress for veteran football players during match is considerable. In this specific elderly population, the kinetics of exercise-induced cardiac troponin I (cTnI) and B-Type natriuretic peptide (BNP) could potentially be related to cardiovascular risk factors (CVRF) and cardiovascular disease and are therefore be investigated for their usefulness as an complement to established screening measures.

METHODS

cTnI and BNP was measured in 112 veteran football players (age: 51 ± 10 years) within 30 minutes pre- and post-match. Players with elevated cTnI (cTnI-positive) and a control group (out of the 112 veteran players) with normal cTnI (cTnI-negative) underwent cardiac follow-up 4.2 ± 3.5 months post-match, comprising history, resting and stress ECG (including 30 minutes pre- and post cTnI and BNP), and echocardiography.

RESULTS

In 33 players (29%) cTnI and in 6 players BNP (5%) exceeded the upper range limit for increased risk of myocardial damage (cTnI ≥ 5 ng/l) and myocardial wall stress (BNP ≥ 100 pg/ml) post-match, respectively. No correlation was observed between Δ cTnI (pre- vs. post-match) and the number of CVRF (r = -0.06, p = 0.50). Follow-up was conducted in 62 players (31 cTnI-positive and 31 cTnI-negative players) of which 6 (10%, 3 cTnI positive and 3 cTnI negative players) had cardiac abnormalities (hypertrophic cardiomyopathy n = 2, coronary artery disease n = 2, coronary artery anomaly n = 1, hypertensive heart disease n = 1).

CONCLUSION

Veterans' football matches elicit increases in BNP and particularly cTnI in a considerable number of players. However, these biochemical alterations do not indicate acute cardiac damage as evidenced by follow-up. Routine determination of cardiac biomarkers is unlikely to improve cardiovascular screening in veteran football players.

The Acute Impact of Endurance Exercise on Right Ventricular Structure and Function: A Systematic Review and Meta-analysis

There have been many studies since the late 1980s investigating the effect of endurance exercise on the left ventricle. More recently, attention has shifted to the right heart, with suggestions that endurance exercise may have a detrimental effect on the right ventricle. This systematic review and meta-analysis summarizes and critiques 26 studies, including 649 athletes, examining the acute impact of endurance exercise on the right ventricle. We also present a subanalysis contrasting ultraendurance with endurance exercise. Finally, we identify areas for future research, such as the influence of sex, ethnicity, and age.

Insult of Ultraendurance Events on Blood Pressure: A Systematic Review and Meta-Analysis

The rise of ultraendurance sports in the past two decades warrants evaluation of the impact on the heart and vessels of a growing number of athletes participating. Blood pressure is a simple, inexpensive method to evaluate one dimension of an athlete's cardiovascular health. No systematic review or meta-analysis to date has chronicled and delineated the effects of ultraendurance races, such as ultramarathons, marathons, half-marathons, and Ironman triathlon events, specifically on heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP), and mean arterial pressure (MAP) measurements in supine and standing positions before and after the event. This meta-analysis reviews the effects of ultraendurance events on positional and calculated hemodynamic values. Data were extracted from 38 studies and analyzed using a random effects model with a total of 1,645 total blood pressure measurements. Of these, 326 values were obtained from a standing position, and 1,319 blood pressures were taken supine. Pre-race and post-race measurements were evaluated for clinical significance using established standards of hypotension and orthostasis. HR and calculated BP features, such as PP and MAP, were evaluated. Across all included studies, the mean supine post-race HR increased by 21±8 beats per minute (bpm) compared to pre-race values. The mean standing post-race HR increased by 23±14 bpm when compared with pre-race HR. Overall, there was a mean SBP decrease of 19±9 mmHg and a DBP decrease of 9±5 mmHg post-race versus pre-race values. MAP variations reflected SBP and DBP changes. The mean supine and standing pre-race blood pressures across studies were systolic (126±7; 124±14) and diastolic (76±6; 75±12), suggesting that some athletes may enter races with existing hypertension. The post-race increase in the mean HR and decline in mean blood pressure across examined studies suggest that during long-term events, ultramarathon athletes perform with relatively asymptomatic hypotension.

Cardiac Troponin Release after Exercise in Healthy Young Athletes: A Systematic Review

Cardiac troponin (cTn) is a recognized marker used to assess damage to the heart muscle. Actual research has indicated that the levels of cTn increase after doing exercise in individuals who are in good health, and this is believed to be a result of a normal cellular process rather than a pathological one. The main goal of this study was to investigate the evidence of a postexercise release of cTn in child and adolescent athletes (6-17.9 years old) of different ages, sex, and sports disciplines. The Web of Science, MEDLINE, and Scopus databases were used to conduct the research up to March 2023. Three hundred and twenty-eight records were identified from the databases, however, only twenty-three studies were included in the review after being screened and quality-assessed by two independent authors. The gender, age of the participants, maturational status, and training level of the participants, the timing of sample collection, the exercise modality, and the number of participants with values above the cut-off reference were the data analyzed. Males, older young people, and individual sports seemed to have higher levels of serum cTn after practice exercise. Different methodologies, analyzers, and cut-off reference values make it difficult to compare the data among studies.

Elevated cfDNA after exercise is derived primarily from mature polymorphonuclear neutrophils, with a minor contribution of cardiomyocytes

Strenuous physical exercise causes a massive elevation in the concentration of circulating cell-free DNA (cfDNA), which correlates with effort intensity and duration. The cellular sources and physiological drivers of this phenomenon are unknown. Using methylation patterns of cfDNA and associated histones, we show that cfDNA in exercise originates mostly in extramedullary polymorphonuclear neutrophils. Strikingly, cardiomyocyte cfDNA concentration increases after a marathon, consistent with elevated troponin levels and indicating low-level, delayed cardiac cell death. Physical impact, low oxygen levels, and elevated core body temperature contribute to neutrophil cfDNA release, while muscle contraction, increased heart rate, β-adrenergic signaling, or steroid treatment fail to cause elevation of cfDNA. Physical training reduces neutrophil cfDNA release after a standard exercise, revealing an inverse relationship between exercise-induced cfDNA release and training level. We speculate that the release of cfDNA from neutrophils in exercise relates to the activation of neutrophils in the context of exercise-induced muscle damage.

Investigating the roles of exercise intensity and biological sex on postexercise alterations in cardiac function

The term exercise-induced cardiac fatigue (EICF) has typically been used to describe a transient reduction in cardiac function following prolonged-strenuous exercise. Recent evidence demonstrates that EICF can occur following only 45 min of high-intensity exercise when assessed using exercising stress echocardiography. This investigation sought to examine whether sprint intervals (SIT; 6 × 30 s Wingate tests), or 90-min moderate-cycling with sprint intervals (MIX; 90 min with 1 × 30 s Wingate test every 15 min) would cause greater EICF than 90 min (CON) or 3 h (LONG) moderate-cycling assessed using stress echocardiography, with a secondary aim to interrogate sex differences in EICF. Seventeen participants (M: 9, F: 8) underwent three cycling sessions with stress-echocardiography performed before-and-after each condition at a target heart rate (HR) of 100 beats·min^-1, with the CON testing occurring at the mid-point of the 3 h LONG condition. For all conditions, measures of left ventricular (LV) systolic [stroke volume, ejection fraction (EF), peak longitudinal strain, isovolumetric contraction time, S') and diastolic (E/A, E', isovolumetric relaxation time, longitudinal strain rate) function were reduced after exercise (all P < 0.05). In the right ventricle (RV), systolic function was reduced (tricuspid annular plane systolic excursion, S', peak longitudinal strain and strain rate) following all conditions, and fractional area change was reduced to the greatest degree following SIT (condition × time, P = 0.01). Females demonstrated lesser impairments in LV EF, and elastance (ESP/ESV) compared with males (P < 0.05). Markers of EICF occurred similarly following all cycling loads, suggesting the functional changes may be due to altered loading conditions and reduced stress-echocardiography workload. However, males experienced greater cardiac alterations in some measures, likely due to greater changes in postexercise loading conditions.NEW & NOTEWORTHY This investigation sought to determine the role of exercise intensity on the magnitude of exercise-induced cardiac fatigue using stress echocardiography to maintain loading conditions, with a secondary purpose of assessing sex differences. Unexpectedly, it was found that all cycling loads elicited the same magnitude of functional alteration, which likely represents a common response to exercise and stress echocardiography, rather than intrinsic cardiac impairment. Males demonstrated greater alterations than females, likely due to sex differences in postexercise hemodynamics.

Can the Heart Get an Overuse Sports Injury?

Can the Heart Get an Overuse Sports Injury?Recent studies suggest that vigorous endurance exercise increases markers of cardiomyocyte injury and that lifelong endurance exercise may increase myocardial scarring, coronary artery atherosclerosis, AF, and aortic dilatation. This review summarizes the evidence linking these conditions with physical exertion and an approach to their management.

Effects of Breed, Exercise, and a Two-Month Training Period on NT-proBNP-Levels in Athletic Dogs

N-terminal pro-b-type natriuretic peptide (NTproBNP) is a cardiac biomarker used to detect myocardial wall stress. Physical activity and cardiac disease can affect serum NTproBNP concentrations. In people, different types of physical activity have different effects on NTproBNP. Our hypothesis was that physical activity and training have an effect on NTproBNP concentrations depending on the type of exercise and the intensity. Seven German Shepherd dogs (GSD) under military training performing short bursts of fast-paced interval exercise and seven Eurohounds (EHs) training for racing competition with endurance exercise were included in the study. Blood samples were taken at enrollment (T₀) and after a two-month (T_2mth) training period; on both occasions, the samples were acquired before and after physical exercise. An echocardiographic evaluation was performed at T₀. Echocardiographic heart size was larger in the EHs compared to the GSDs. The NTproBNP concentration was higher in the EHs than in the GSDs before and after exercise at T₀ and T_2mth. Echocardiographic parameters of heart size and wall thickness correlated with NTproBNP at T₀ before and after exercise. Exercise induced an elevation of NTproBNP in the EHs at T₀ and T_2mth, while in the GSDs this was observed only at T₀. In the EHs, post exercise was associated with higher NTproBNP at T_2mth compared to T₀, while in the GSDs the opposite pattern was noticed. From our study, the serum NTproBNP concentration differs between breeds. Intense physical activity causes an increase in NTproBNP. A two-month training period does not affect the NTproBNP concentration at rest. Intense physical activity may increase NTproBNP above the reference range in individual dogs.

May Strenuous Endurance Sports Activity Damage the Cardiovascular System of Healthy Athletes? A Narrative Review

The positive effects of physical activity are countless, not only on the cardiovascular system but on health in general. However, some studies suggest a U-shape relationship between exercise volume and effects on the cardiovascular system. On the basis of this perspective, moderate-dose exercise would be beneficial compared to a sedentary lifestyle, while very high-dose physical activity would paradoxically be detrimental. We reviewed the available evidence on the potential adverse effects of very intense, prolonged exercise on the cardiovascular system, both acute and chronic, in healthy athletes without pre-existing cardiovascular conditions. We found that endurance sports activities may cause reversible electrocardiographic changes, ventricular dysfunction, and troponin elevation with complete recovery within a few days. The theory that repeated bouts of acute stress on the heart may lead to chronic myocardial damage remains to be demonstrated. However, male veteran athletes with a long sports career show an increased prevalence of cardiovascular abnormalities such as electrical conduction delay, atrial fibrillation, myocardial fibrosis, and coronary calcifications compared to non-athletes. It must be underlined that the cause-effect relationship between such abnormalities and the exercise and, most importantly, the prognostic relevance of such findings remains to be established.

Sex-Specific Physiological Responses to Ultramarathon

PURPOSE

Despite a growing body of literature on the physiological responses to ultramarathon, there is a paucity of data in females. This study assessed the female physiological response to ultramarathon and compared the frequency of perturbations to a group of race- and time-matched males.

METHODS

Data were collected from 53 contestants of an ultramarathon trail race at the Ultra-Trail du Mont-Blanc (UTMB®) in 2018/19. Before and within 2 h of the finish, participants underwent physiological assessments, including blood sampling for biomarkers (creatine kinase-MB isoenzyme [CK-MB], cardiac troponin I [cTnI], brain natriuretic peptide [BNP], and creatinine [Cr]), pulmonary function testing (spirometry, exhaled NO, diffusing capacities, and mouth pressures), and transthoracic ultrasound (lung comet tails, cardiac function). Data from eight female finishers (age = 36.6 ± 6.9 yr; finish time = 30:57 ± 11:36 h:min) were compared with a group of eight time-matched males (age = 40.3 ± 8.3 yr; finish time = 30:46 ± 10:32 h:min).

RESULTS

Females exhibited significant pre- to postrace increases in BNP (25.8 ± 14.6 vs 140.9 ± 102.7 pg·mL -1 ; P = 0.007) and CK-MB (3.3 ± 2.4 vs 74.6 ± 49.6 IU·L -1 ; P = 0.005), whereas males exhibited significant pre- to postrace increases in BNP (26.6 ± 17.5 vs 96.4 ± 51.9 pg·mL -1 ; P = 0.002), CK-MB (7.2 ± 3.9 vs 108.8 ± 37.4 IU·L -1 ; P = 0.002), and Cr (1.06 ± 0.19 vs 1.23 ± 0.24 mg·dL -1 ; P = 0.028). Lung function declined in both groups, but males exhibited additional reductions in lung diffusing capacities (DL CO = 34.4 ± 5.7 vs 29.2 ± 6.9 mL⋅min -1 ⋅mm Hg -1 , P = 0.004; DL NO = 179.1 ± 26.2 vs 152.8 ± 33.4 mL⋅min -1 ⋅mm Hg -1 , P = 0.002) and pulmonary capillary blood volumes (77.4 ± 16.7 vs 57.3 ± 16.1 mL; P = 0.002). Males, but not females, exhibited evidence of mild postrace pulmonary edema. Pooled effect sizes for within-group pre- to postrace changes, for all variables, were generally larger in males versus females ( d = 0.86 vs 0.63).

CONCLUSIONS

Ultramarathon negatively affects a range of physiological functions but generally evokes more frequent perturbations, with larger effect sizes, in males compared to females with similar race performances.

Predictors of Stress-Delta High-Sensitivity Troponin T in Emergency Department Patients Undergoing Stress Testing

Background and objective

Elevations in high-sensitivity troponin T (hs-TnT) are frequently observed following extreme physical exercise. In light of this, we sought to determine whether specific clinical characteristics are associated with this phenomenon in patients undergoing cardiac exercise tolerance testing (ETT).

Methods

We conducted a retrospective analysis of a prospectively collected biospecimen repository of 257 patients undergoing a stress echocardiogram for possible acute coronary syndrome (ACS). Ischemic electrocardiogram (ECG) changes during ETT and the presence or absence of ischemia on imaging were determined by a board-licensed cardiologist. N-terminal pro-brain natriuretic peptide (NT-proBNP) and hs-TnT assays were obtained immediately before and two hours following ETT. We developed linear regression models including several clinical characteristics to predict two-hour stress-delta hs-TnT. Variable selection was performed using the least absolute shrinkage and selection operator (LASSO).

Results

The mean age of the patients was 52 years [standard deviation (SD): 11.4]; 125 (48.6%) of them were men, and 88 (34.2%) were African-American. Twenty-two patients (8.6%) had ischemia evident on echocardiography, and 31 (12.1%) had ischemic ECG changes during exercise. The mean baseline hs-TnT was 5.6 ng/L (SD: 6.4) and the mean two-hour hs-TnT was 7.1 ng/L (SD: 10.2). Age and ischemic ECG changes were associated with two-hour stress-delta hs-TnT values.

Conclusions

Based on our findings, ischemic changes in stress ECG and age were associated with an increase in hs-TnT levels following exercise during a stress echo.

Tachycardia-Induced Cardiomyopathy in a Young Healthy Patient: A Case Report

Tachycardia-induced cardiomyopathy (TIC) can result in both systolic and/or diastolic ventricular dysfunction as a result of the prolonged fast heart rate which is reversible upon controlling the fast heart rate or arrhythmia. The exact heart rate that can lead to this is not clear, however, a heart rate > 100 in general needs attention. Tachycardia-induced cardiomyopathy is a well-established cause of left ventricular dysfunction which usually happens due to an increased atrial or ventricular rate. The incidence of TIC is very low although the exact incidence is unclear. It should be considered in all patients with dilated cardiomyopathy or those with no obvious explanation for dilated cardiomyopathy and in presence of tachycardia or atrial fibrillation with a rapid ventricular response. Tachycardia-induced cardiomyopathy has also been labeled as arrhythmia-induced cardiomyopathy lately. We present a case of a 50-year-old patient who presented with a fever of 39^oC, feeling generally unwell, had a sore throat, and collapsed at home after several episodes of vomiting after two days of intense exercise. He was diagnosed with suspected tonsillitis and was treated with co-amoxiclav. He was exercising over 10 hours weekly for the last two months in the gym for the Ironman triathlon in London. An echocardiogram showed severe left ventricular systolic dysfunction (LVSD) with a left ventricular ejection fraction (LVEF) of 25%. An electrocardiogram showed sinus tachycardia with a right bundle branch block (RBBB). Cardiac magnetic resonance imaging (CMR) showed normal biventricular function with an ejection fraction (EF) of 71% four months later. The patient was diagnosed with tachycardia-induced cardiomyopathy. This case is unique as the patient presented with transient severe LVSD after training for the ironman triathlon and spontaneous recovery.

Exercise as an Aging Mimetic: A New Perspective on the Mechanisms Behind Exercise as Preventive Medicine Against Age-Related Chronic Disease

Age-related chronic diseases are among the most common causes of mortality and account for a majority of global disease burden. Preventative lifestyle behaviors, such as regular exercise, play a critical role in attenuating chronic disease burden. However, the exact mechanism behind exercise as a form of preventative medicine remains poorly defined. Interestingly, many of the physiological responses to exercise are comparable to aging. This paper explores an overarching hypothesis that exercise protects against aging/age-related chronic disease because the physiological stress of exercise mimics aging. Acute exercise transiently disrupts cardiovascular, musculoskeletal, and brain function and triggers a substantial inflammatory response in a manner that mimics aging/age-related chronic disease. Data indicate that select acute exercise responses may be similar in magnitude to changes seen with +10-50 years of aging. The initial insult of the age-mimicking effects of exercise induces beneficial adaptations that serve to attenuate disruption to successive "aging" stimuli (i.e., exercise). Ultimately, these exercise-induced adaptations reduce the subsequent physiological stress incurred from aging and protect against age-related chronic disease. To further examine this hypothesis, future work should more intricately describe the physiological signature of different types/intensities of acute exercise in order to better predict the subsequent adaptation and chronic disease prevention with exercise training in healthy and at-risk populations.

Strenuous Endurance Exercise and the Heart: Physiological versus Pathological Adaptations

Although the benefits of regular physical activity on cardiovascular health are well established, the effects of strenuous endurance exercise (SEE) have been a matter of debate since ancient times. In this article, we aim to provide a balanced overview of what is known about SEE and the heart-from epidemiological evidence to recent cardiac imaging findings. Lifelong SEE is overall cardioprotective, with endurance master athletes showing in fact a youthful heart. Yet, some lines of research remain open, such as the need to elucidate the time-course and potential relevance of transient declines in heart function (or increases in biomarkers of cardiac injury) with SEE. The underlying mechanisms and clinical relevance of SEE-associated atrial fibrillation, myocardial fibrosis, or high coronary artery calcium scores also remain to be elucidated. © 2022 American Physiological Society. Compr Physiol 12:1-19, 2022.

Cardiorespiratory Fitness and Mortality Risk Across the Spectra of Age, Race, and Sex

BACKGROUND

Cardiorespiratory fitness (CRF) is inversely associated with all-cause mortality. However, the association of CRF and mortality risk for different races, women, and elderly individuals has not been fully assessed.

OBJECTIVES

The aim of this study was to evaluate the association of CRF and mortality risk across the spectra of age, race, and sex.

METHODS

A total of 750,302 U.S. veterans aged 30 to 95 years (mean age 61.3 ± 9.8 years) were studied, including septuagenarians (n = 110,637), octogenarians (n = 26,989), African Americans (n = 142,798), Hispanics (n = 35,197), Native Americans (n = 16,050), and women (n = 45,232). Age- and sex-specific CRF categories (quintiles and 98th percentile) were established objectively on the basis of peak METs achieved during a standardized exercise treadmill test. Multivariable Cox models were used to estimate HRs and 95% CIs for mortality across the CRF categories.

RESULTS

During follow-up (median 10.2 years, 7,803,861 person-years of observation), 174,807 subjects died, averaging 22.4 events per 1,000 person-years. The adjusted association of CRF and mortality risk was inverse and graded across the age spectrum, sex, and race. The lowest mortality risk was observed at approximately 14.0 METs for men (HR: 0.24; 95% CI: 0.23-0.25) and women (HR: 0.23; 95% CI: 0.17-0.29), with no evidence of an increase in risk with extremely high CRF. The risk for least fit individuals (20th percentile) was 4-fold higher (HR: 4.09; 95% CI: 3.90-4.20) compared with extremely fit individuals.

CONCLUSIONS

The association of CRF and mortality risk across the age spectrum (including septuagenarians and octogenarians), men, women, and all races was inverse, independent, and graded. No increased risk was observed with extreme fitness. Being unfit carried a greater risk than any of the cardiac risk factors examined.

Exercise-induced myocardial edema in master triathletes: Insights from cardiovascular magnetic resonance imaging

Background

Strenuous exercise has been associated with functional and structural cardiac changes due to local and systemic inflammatory responses, reflecting oxidative, metabolic, hormonal, and thermal stress, even in healthy individuals. We aimed to assess changes in myocardial structure and function using cardiovascular magnetic resonance (CMR) imaging in master triathletes early after a full-distance Ironman Triathlon race.

Materials and methods

Ten master triathletes (age 45 ± 8 years) underwent CMR within 3 h after a full-distance Ironman Triathlon race (3.8 km swimming, 180 km cycling, and 42.2 km running) completed with a mean time of 12 ± 1 h. All the triathletes had a 30-day follow-up CMR. Cine balanced steady-state free precession, T2-short tau inversion recovery (STIR), tagging, and late gadolinium enhancement (LGE) imaging sequences were performed on a 1.5-T MR scanner. Myocardial edema was defined as a region with increased T2 signal intensity (SI) of at least two SDs above the mean of the normal myocardium. The extent of myocardial edema was expressed as the percentage of left ventricular (LV) mass. Analysis of LV strain and torsion by tissue tagging included the assessment of radial, longitudinal, and circumferential peak systolic strain, rotation, and twist.

Results

Compared with postrace, biventricular volumes, ejection fraction, and LV mass index remained unchanged at 30-day follow-up. Global T2 SI was significantly higher in the postrace CMR (postrace 10.5 ± 6% vs. follow-up 3.9 ± 3.8%, P = 0.004) and presented with a relative apical sparing distribution (P < 0.001) matched by reduction of radial peak systolic strain of basal segments (P = 0.003). Apical rotation and twist were significantly higher immediately after the competition compared with follow-up (P < 0.05).

Conclusion

Strenuous exercise in master triathletes is associated with a reversible regional increase in myocardial edema and reduction of radial peak systolic strain, both presenting with a relative apical sparing pattern.

Could Repeated Cardio-Renal Injury Trigger Late Cardiovascular Sequelae in Extreme Endurance Athletes?

Regular exercise confers multifaceted and well-established health benefits. Yet, transient and asymptomatic increases in markers of cardio-renal injury are commonly observed in ultra-endurance athletes during and after competition. This has raised concerns that chronic recurring insults could cause long-term cardiac and/or renal damage. Indeed, extreme endurance exercise (EEE) over decades has sometimes been linked with untoward cardiac effects, but a causal relation with acute injury markers has not yet been established. Here, we summarize the current knowledge on markers of cardiac and/or renal injury in EEE athletes, outline the possible interplay between cardiac and kidney damage, and explore the roles of various factors in the development of potential exercise-related cardiac damage, including underlying diseases, medication, sex, training, competition, regeneration, mitochondrial dysfunction, oxidative stress, and inflammation. In conclusion, despite the undisputed health benefits of regular exercise, we speculate, based on the intimate link between heart and kidney diseases, that in rare cases excessive endurance sport may induce adverse cardio-renal interactions that under specific, hitherto undefined conditions could result in persistent cardiac damage. We highlight future research priorities and provide decision support for athletes and clinical consultants who are seeking safe strategies for participation in EEE training and competition.

Exercise-Induced Atrial Remodeling in Female Amateur Marathon Runners Assessed by Three-Dimensional and Speckle Tracking Echocardiography

Endurance athletes have an increased risk of atrial remodeling and atrial arrhythmias. However, data regarding atrial adaptation to physical exercise in non-elite athletes are limited. Even less is known about atrial performance in women. We aimed to elucidate exercise-induced changes in atrial morphology and function in female amateur marathon runners using three-dimensional (3D) echocardiography and two-dimensional (2D) speckle tracking echocardiography (STE). The study group consisted of 27 female (40 ± 7 years) amateur athletes. Right (RA) and left atrial (LA) measures were assessed three times: 2–3 weeks before the marathon (stage 1), immediately after the run (stage 2), and 2 weeks after the competition (stage 3). Directly after the marathon, a remarkable RA dilatation, as assessed by RA maximal volume (RAVmax, 31.3 ± 6.8 vs. 35.0 ± 7.0 ml/m²; p = 0.008), with concomitant increase in RA contractile function [RA active emptying fraction (RA active EF), 27.7 ± 8.6 vs. 35.0 ± 12.1%; p = 0.014; RA peak atrial contraction strain (RA PACS) 13.8 ± 1.8 vs. 15.6 ± 2.5%; p = 0.016] was noticed. There were no significant changes in LA volumes between stages, while LA active EF (34.3 ± 6.4 vs. 39.4 ± 8.6%; p = 0.020), along with LA PACS (12.8 ± 2.1 vs. 14.9 ± 2.7%; p = 0.002), increased post race. After the race, an increase in right ventricular (RV) dimensions (RV end-diastolic volume index, 48.8 ± 11.0 vs. 60.0 ± 11.1 ml/m²; p = 0.001) and a decrease in RV function (RV ejection fraction, 54.9 ± 6.3 vs. 49.1 ± 6.3%; p = 0.006) were observed. The magnitude of post-race RV dilatation was correlated with peak RA longitudinal strain deterioration (r = −0.56, p = 0.032). The measured parameters did not differ between stages 1 and 3. In female amateur athletes, apart from RV enlargement and dysfunction, marathon running promotes transient biatrial remodeling, with more pronounced changes in the RA. Post-race RA dilatation and increment of the active contraction force of both atria are observed. However, RA reservoir function diminishes in those with post-race RV dilation.

Acute effects of high intensity training on cardiac function: a pilot study comparing subjects with type 2 diabetes to healthy controls

This study evaluated acute cardiac stress after a high-intensity interval training session in patients with type 2 diabetes (T2D) versus healthy controls. High intensity aerobic exercise was performed by 4 × 4-min intervals (90-95% of maximal heart rate), followed by a ramp protocol to peak oxygen uptake. Echocardiography was performed before and 30 min after exercise. Holter electrocardiography monitored heart rhythms 24 h before, during, and 24 h after the exercise. Left atrial end-systolic volume, peak early diastolic mitral annular velocity, and the ratio of peak early to late diastolic mitral inflow velocity were reduced by approximately 18%, 15%, and 31%, respectively, after exercise across groups. Left ventricular end-diastolic wall thickness was the only echo parameter that significantly differed between groups in response to exercise. The T2D group had a rate of supraventricular extrasystoles per hour that was 265% greater than that of the controls before exercise, which remained higher after exercise. A single exhaustive exercise session impaired left ventricular diastolic function in both groups. The findings also indicated impaired right ventricular function in patients with T2D after exercise.ClinicalTrials.gov Identifier: NCT02998008.

Cardiac Troponin-T Release After Sport and Differences by Age, Sex, Training Type, Volume, and Intensity: A Critical Review

BACKGROUND

Postexercise release of cardiac troponin (cTn) is a well-known phenomenon, although the influence of various confounders remains unclear. The aim of this critical review was to analyze the postexercise release of cTn according to age, sex, different types of sport, exercise intensity and duration, and training level.

DATA SOURCES

A literature search was performed within the National Library of Medicine using the following keywords: cTn, peak, release, and exercise. The search was further refined by adding the keywords athletes, children/adolescents, and sport.

MAIN RESULTS

For final analysis, 52 studies were included: 43 adult studies, 4 pediatric studies, and 5 with a mixed population of adults and children. Several studies have investigated the kinetics of cTn response after exercise with different biomarkers. The current evidence suggests that sport intensity and duration have significant effects on postexercise cTn elevation, whereas the influence of the type of sport, age, and sex have been not completely defined yet. Most data were obtained during endurance races, whereas evidence is limited (or almost absent), particularly for mixed sports. Data on young adults and professional athletes are limited. Finally, studies on women are extremely limited, and those for non-White are absent.

CONCLUSIONS

Postexercise release of cTn can be observed both in young and master athletes and usually represents a physiological phenomenon; however, more rarely, it may unmask a subclinical cardiac disease. The influence of different confounders (age, sex, sport type/intensity/duration, and training level) should be better clarified to establish individualized ranges of normality for postexercise cTn elevation.

Mountain Ultra-Marathon (UTMB) Impact on Usual and Emerging Cardiac Biomarkers

The number of participants in ultra-marathons is increasing. However, the data regarding the impact of this type of exercise on the cardiovascular system are contradictory. In our study, 28 ultra-trail runners were enrolled. Blood samples were collected at three time points: immediately before, immediately after, and 7 days after the ultra-marathon. Different biomarkers were measured. Immediately after the race, the blood concentrations of the different cardiac and inflammatory biomarkers increased significantly. Interestingly, some biomarkers remained high even after 7 days of recovery.

Auto-antibodies to cardiomyocyte proteins dynamics at different stages of simulated muscle loads

Relevance. Early diagnosis of chronic overstress among athletes remains an important problem for coaches and specialists in the field of sports physiology and medicine. The goal is to study in an animal model the dynamics of autoimmune response to physical activity of different duration and intensity and to establish the prospects of the method of determining autoantibodies to cardiomyocyte proteins as an indicator of the morphofunctional state of the heart in the conditions of adaptation to muscle loads. Materials and Methods. The study was conducted in male white rats. Animals were subjected to 9 weeks of training simulated with treadban. The intensity of the load changed the angle of inclination and the speed of the tape. The amount of cardiospecific autoantibodies (auto-AB) to troponin I, to alpha-actin 1, to the human cardiac beta-myosin heavy chain MYH7 was determined in the blood by enzyme immunoassay. The relative heart mass was measured. Histomorphological assessment of cardiomyocyte condition was carried out. Statistical processing was carried out using the Student and Mann-Whitney criteria. Results and Discussion. Animal training was accompanied by moderate cardiac hypertrophy of pathological changes in cardiomyocytes. Heart weight increased by 6.9 %; 10.6 %; 12.9 % in the dynamics of 6-8-9 weeks of training. Concentrations of auto-AB to troponin I and to alpha-actin 1 were characterized by cyclicity, manifested by an increase in week 2 and a decrease by the 8th and 9th weeks of training. In the dynamics of 0-2-8-9 weeks of the experiment, the amount of auto-AB to troponin I was: 3.10.3; 4.20.9; 2.10.2; 2.00.04 ng/ml. For auto-AB to actin: 26.71.2; 31.31.4; 13.71.8; 12.11.6 ng/ml, respectively. The level of auto-AB to beta-myosin was manifested by a decrease in the dynamics of 0-6-9 weeks of training and amounted to: 16.30.9; 10.91.5; 8.20.8; 9.6 0.9 ng/ml. Conclusion. The results of determining cardiospecific auto-AB demonstrate a clear response of the immune system to the processes taking place in cardiomyocytes, which makes it possible to recommend further study of the method of determining auto-AB to cardiomyocyte proteins as a diagnostic test of the functional state of the heart muscle during the period of adaptation to physical activity.

Auto-antibodies to cardiomyocyte proteins dynamics at different stages of simulated muscle loads

Relevance. Early diagnosis of chronic overstress among athletes remains an important problem for coaches and specialists in the field of sports physiology and medicine. The goal is to study in an animal model the dynamics of autoimmune response to physical activity of different duration and intensity and to establish the prospects of the method of determining autoantibodies to cardiomyocyte proteins as an indicator of the morphofunctional state of the heart in the conditions of adaptation to muscle loads. Materials and Methods. The study was conducted in male white rats. Animals were subjected to 9 weeks of training simulated with treadban. The intensity of the load changed the angle of inclination and the speed of the tape. The amount of cardiospecific autoantibodies (auto-AB) to troponin I, to alpha-actin 1, to the human cardiac beta-myosin heavy chain MYH7 was determined in the blood by enzyme immunoassay. The relative heart mass was measured. Histomorphological assessment of cardiomyocyte condition was carried out. Statistical processing was carried out using the Student and Mann-Whitney criteria. Results and Discussion. Animal training was accompanied by moderate cardiac hypertrophy of pathological changes in cardiomyocytes. Heart weight increased by 6.9 %; 10.6 %; 12.9 % in the dynamics of 6-8-9 weeks of training. Concentrations of auto-AB to troponin I and to alpha-actin 1 were characterized by cyclicity, manifested by an increase in week 2 and a decrease by the 8th and 9th weeks of training. In the dynamics of 0-2-8-9 weeks of the experiment, the amount of auto-AB to troponin I was: 3.10.3; 4.20.9; 2.10.2; 2.00.04 ng/ml. For auto-AB to actin: 26.71.2; 31.31.4; 13.71.8; 12.11.6 ng/ml, respectively. The level of auto-AB to beta-myosin was manifested by a decrease in the dynamics of 0-6-9 weeks of training and amounted to: 16.30.9; 10.91.5; 8.20.8; 9.6 0.9 ng/ml. Conclusion. The results of determining cardiospecific auto-AB demonstrate a clear response of the immune system to the processes taking place in cardiomyocytes, which makes it possible to recommend further study of the method of determining auto-AB to cardiomyocyte proteins as a diagnostic test of the functional state of the heart muscle during the period of adaptation to physical activity.

Post-marathon Decline in Right Ventricular Radial Motion Component Among Amateur Sportsmen

Moderate physical activity has a positive impact on health, although extreme forms of sport such as marathon running may trigger exercise-induced cardiac fatigue. The explicit distinction between the right ventricular (RV) physiological response to training and maladaptive remodeling has not yet been determined. In this study, we aimed to analyze the impact of running a marathon on RV mechanics in amateur athletes using three-dimensional (3D) echocardiography (ECHO) and the ReVISION method (RV separate wall motion quantification). A group of 34 men with a mean age of 40 ± 8 years who successfully finished a marathon underwent ECHO three times, i.e., 2 weeks before the marathon (stage I), at the marathon finish line (stage II), and 2 weeks after the marathon (stage III). The ECHO findings were then correlated with the concentrations of biomarkers related to myocardial injury and overload and also obtained at the three stages. On finishing the marathon, the amateur athletes were found to have a significant (p < 0.05) increase in end-diastolic (with a median of 51.4 vs. 57.0 ml/m²) and end-systolic (with a median of 24.9 vs. 31.5 ml/m²) RV volumes indexed to body surface area, reduced RV ejection fraction (RVEF) (with a median of 51.0% vs. 46.0%), and a decrease in RV radial shortening [i.e., radial EF (REF)] (with a mean of 23.0 ± 4.5% vs. 19.3 ± 4.2%), with other RV motion components remaining unchanged. The post-competition decrease in REF was more evident in runners with larger total volume of trainings (R² = 0.4776, p = 0.0002) and higher concentrations of high-sensitivity cardiac troponin I (r = 0.43, p < 0.05) during the preparation period. The decrease in REF was more prominent in the training of marathoners more than 47 km/week. At stage II, marathoners with a more marked decrease in RVEF and REF had higher galectin-3 (Gal-3) levels (r = −0.48 and r = −0.39, respectively; p < 0.05). Running a marathon significantly altered the RV performance of amateur athletes. Transient impairment in RV systolic function resulted from decreased radial shortening, which appeared in those who trained more extensively. Observed ECHO changes correlated with the concentrations of the profibrotic marker Gal-3.

Exercise-Induced Cardiac Troponin Elevations: From Underlying Mechanisms to Clinical Relevance

Supplemental Digital Content is available in the text.

Serological assessment of cardiac troponins (cTn) is the gold standard to assess myocardial injury in clinical practice. A greater magnitude of acutely or chronically elevated cTn concentrations is associated with lower event-free survival in patients and the general population. Exercise training is known to improve cardiovascular function and promote longevity, but exercise can produce an acute rise in cTn concentrations, which may exceed the upper reference limit in a substantial number of individuals. Whether exercise-induced cTn elevations are attributable to a physiological or pathological response and if they are clinically relevant has been debated for decades. Thus far, exercise-induced cTn elevations have been viewed as the only benign form of cTn elevations. However, recent studies report intriguing findings that shed new light on the underlying mechanisms and clinical relevance of exercise-induced cTn elevations. We will review the biochemical characteristics of cTn assays, key factors determining the magnitude of postexercise cTn concentrations, the release kinetics, underlying mechanisms causing and contributing to exercise-induced cTn release, and the clinical relevance of exercise-induced cTn elevations. We will also explain the association with cardiac function, correlates with (subclinical) cardiovascular diseases and exercise-induced cTn elevations predictive value for future cardiovascular events. Last, we will provide recommendations for interpretation of these findings and provide direction for future research in this field.

Acute impact of an endurance race on biventricular and biatrial myocardial strain in competitive male and female triathletes evaluated by feature-tracking CMR

Objectives

Cardiac adaptation in endurance athletes is a well-known phenomenon, but the acute impact of strenuous exercise is rarely reported on. The aim of this study was to analyze the alterations in biventricular and biatrial function in triathletes after an endurance race using novel feature-tracking cardiac magnetic resonance (FT-CMR).

Methods

Fifty consecutive triathletes (45 ± 10 years; 80% men) and twenty-eight controls were prospectively recruited, and underwent 1.5-T CMR. Biventricular and biatrial volumes, left ventricular ejection fraction (LVEF), FT-CMR analysis, and late gadolinium imaging (LGE) were performed. Global systolic longitudinal (GLS), circumferential (GCS), and radial strain (GRS) were assessed. CMR was performed at baseline and following an endurance race. High-sensitive troponin T and NT-proBNP were determined. The time interval between race completion and CMR was 2.3 ± 1.1 h (range 1–5 h).

Results

Post-race troponin T (p < 0.0001) and NT-proBNP (p < 0.0001) were elevated. LVEF remained constant (62 ± 6 vs. 63 ± 7%, p = 0.607). Post-race LV GLS decreased by tendency (− 18 ± 2 vs. − 17 ± 2%, p = 0.054), whereas GCS (− 16 ± 4 vs. − 18 ± 4%, p < 0.05) and GRS increased (39 ± 11 vs. 44 ± 11%, p < 0.01). Post-race right ventricular GLS (− 19 ± 3 vs. − 19 ± 3%, p = 0.668) remained constant and GCS increased (− 7 ± 2 vs. − 8 ± 3%, p < 0.001). Post-race left atrial GLS (30 ± 8 vs. 24 ± 6%, p < 0.0001) decreased while right atrial GLS remained constant (25 ± 6 vs. 24 ± 6%, p = 0.519).

Conclusions

The different alterations of post-race biventricular and biatrial strain might constitute an intrinsic compensatory mechanism following an acute bout of endurance exercise. The combined use of strain parameters may allow a better characterization of ventricular and atrial function in endurance athletes.

Key Points

• Triathletes demonstrate a decrease of LV global longitudinal strain by tendency and constant RV global longitudinal strain following an endurance race.

• Post-race LV and RV global circumferential and radial strains increase, possibly indicating a compensatory mechanism after an acute endurance exercise bout.

• Subgroup analyses of male triathletes with focal myocardial fibrosis did not demonstrate alterations in biventricular and biatrial strain after an endurance race.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-08401-y.

The value of perioperative biomarker release for the assessment of myocardial injury or infarction in cardiac surgery

OBJECTIVES

Cardiac biomarkers are indicators of irreversible cell damage. Current myocardial infarction (MI) definitions require concomitant clinical characteristics. For perioperative MI, a correlation of biomarker elevations and mortality has been suggested. Definitions emerged relying on cardiac biomarker release only. This approach is questionable as several clinical and experimental scenarios exist where relevant biomarker release can occur apart from MI.

METHODS

We reviewed the clinical and basic science literature and revealed important aspects regarding the use and interpretation of cardiac biomarker release with special focus on their interpretation in the perioperative setting.

RESULTS

Ischaemic biomarkers may be released without cell death in multiple conditions, such as after endurance runs in athletes, temporary inotropic stimulation in animal models and flow variations in in vitro cell models. In addition, access through atrial tissue during cannulation or concomitant valve procedures adds sources of enzyme release that may not be related to ventricular ischaemia (i.e. MI). Such non-cell death-related mechanisms may explain the lack of poor correlations of enzyme release and long-term outcomes in recent trials. In addition, the 3 main biomarkers, troponin T, I and creatine kinase myocardial band, differ in their release kinetics, which may differentially trigger MI events in trial patients.

CONCLUSIONS

The identification of irreversible myocardial injury in cardiac surgery based only on biomarker release is unreliable. Cell death- and non-cell death-related mechanisms create a mix in the perioperative setting that requires additional markers for proper identification of MI. In addition, the 3 most common ischaemic biomarkers display different release kinetics adding to the confusion. We review the topic.

SUBJ COLLECTION

120, 123.

The impact of an ultra-trail on the dynamic of cardiac, inflammatory, renal and oxidative stress biological markers correlated with electrocardiogram and echocardiogram

The aim of this study was to describe the effects of a 64.2 km ultra-trail on the biomarkers of muscle damage, inflammation and oxidative stress, and compare the results observed with an ECG and an echocardiogram, both performed before and after the race.Thirty-three ultra-trail volunteers (45.8 ± 8.7 years old) were enrolled in our study. Three blood tests were drawn from each runner, one just before (TPRE), one just after (TPOST) and the last 3 h after the end of the race (TPOST3h).All the markers increased. The maximum concentrations observed were at TPOST3h and were significant (p < 0.001) for creatine kinase, creatine kinase isoform MB, high-sensitivity C-reactive protein, uric acid and for the ratio of reduced glutathione to oxidised glutathione. However, in the case of myoglobin, high-sensitive troponin T, N-terminal pro-brain natriuretic peptide, oxidised glutathione, myeloperoxidase, cystatin C and creatinine, the most significant increases were at TPOST (p < 0.001). Modifications were observed in the medical imaging using echocardiography such as reduction of left ventricule end-sytolic and diastolic volumes and left ventricular global longitudinal strain. ECG showed electrical criteria for left ventricular hypertrophy and incomplete right bundle branch block after the race.Endurance races cause significant physiological stress to the body that can be measured by the increase of different biomarkers. From a laboratory perspective, it is important to take into account the possible exercise performed previous to the testing to avoid a misinterpretation of the results. From a training perspective, due to these increases in biomarkers, it is recommended that runners wait at least 72 h after an ultra-trail before subsequent training. In addition a transient impairment of ventricular function due to dehydration were observed.

Cardiac troponin and defining myocardial infarction

The 4th Universal Definition of Myocardial Infarction has stimulated considerable debate since its publication in 2018. The intention was to define the types of myocardial injury through the lens of their underpinning pathophysiology. In this review, we discuss how the 4th Universal Definition of Myocardial Infarction defines infarction and injury and the necessary pragmatic adjustments that appear in clinical guidelines to maximize triage of real-world patients.

Marathon-Induced Cardiac Fatigue: A Review over the Last Decade for the Preservation of the Athletes' Health

AIM

To provide a state-of-the-art review of the last 10 years focusing on cardiac fatigue following a marathon.

METHODS

The PubMed, Bookshelf and Medline databases were queried during a time span of 10 years to identify studies that met the inclusion criteria. Twenty-four studies focusing only on the impact of marathons on the cardiac function and factors involved in cardiac fatigue were included in this review.

RESULTS

Sixteen studies focused on the impact of marathons on several biomarkers (e.g., C-reactive protein, cardiac troponin T). Seven studies focused on the left (LV) or right (RV) ventricular function following a marathon and employed cardiac magnetic resonance, echocardiography, myocardial speckle tracking and heart rate variability to analyze global and regional LV or RV mechanics and the impact of the autonomic nervous system on cardiac function. One study focused on serum profiling and its association with cardiac changes after a marathon.

CONCLUSIONS

This review reported a negligible impact of marathons on LV and RV systolic and contractile function but a negative impact on LV diastolic function in recreational runners. These impairments are often associated with acute damage to the myocardium. Thus, the advice of the present review to athletes is to adapt their training and have a regular medical monitoring to continue to run marathons while preserving their cardiac health.

Cardiac Biomarkers and Autoantibodies in Endurance Athletes: Potential Similarities with Arrhythmogenic Cardiomyopathy Pathogenic Mechanisms

The “Extreme Exercise Hypothesis” states that when individuals perform training beyond the ideal exercise dose, a decline in the beneficial effects of physical activity occurs. This is due to significant changes in myocardial structure and function, such as hemodynamic alterations, cardiac chamber enlargement and hypertrophy, myocardial inflammation, oxidative stress, fibrosis, and conduction changes. In addition, an increased amount of circulating biomarkers of exercise-induced damage has been reported. Although these changes are often reversible, long-lasting cardiac damage may develop after years of intense physical exercise. Since several features of the athlete’s heart overlap with arrhythmogenic cardiomyopathy (ACM), the syndrome of “exercise-induced ACM” has been postulated. Thus, the distinction between ACM and the athlete’s heart may be challenging. Recently, an autoimmune mechanism has been discovered in ACM patients linked to their characteristic junctional impairment. Since cardiac junctions are similarly impaired by intense physical activity due to the strong myocardial stretching, we propose in the present work the novel hypothesis of an autoimmune response in endurance athletes. This investigation may deepen the knowledge about the pathological remodeling and relative activated mechanisms induced by intense endurance exercise, potentially improving the early recognition of whom is actually at risk.

Associations between cardiac troponin I and cardiovascular parameters after 12-week endurance training in young moderately trained amateur athletes

Background

Previous studies were conducted only on elite athletes, and they investigate acute training responses of cardiac troponin I (CTnI). However, cardiac troponin was found to be elevated in young and inexperienced athletes than adults, and immature myocardium is more susceptible to injury, which needs further consideration.

Aim

Therefore, we aimed to observe the association between CTnI and cardiovascular parameters in response to chronic endurance training adaptation in young athletes.

Methods

Fifteen participants aged (19.5±1.3) years were selected and placed in endurance running at 70%–80% HRmax intensity for 35 min per training for the first week and additional 2 min each week from the second to the last week for 12 weeks. Serum cardiac troponin and cardiovascular parameters were assessed at pre-training and after 12 weeks of training.

Result

We find a significant CTnI level (p<0.05) and it is positively correlated with systolic blood pressure (BP) (r=0.425). Moreover, CTnI was statistically significant (p<0.01) and positively associated with mean arterial pressure (r=0.516) with a moderate correlation. Besides, CTnI showed a significant (p<0.001) and positive relationship with resting heart rate (r=0.605) and a moderate correlation. We did not find a significant relationship between CTnI and diastolic BP in response to endurance training adaptation.

Conclusion

In conclusion, serum CTnI was significantly and positively associated with cardiovascular parameters in young amateur athletes in response to 12-week endurance training adaptation.

Cardiac Biomarkers Following Marathon Running: Is Running Time a Factor for Biomarker Change?

PURPOSE

Plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponin T levels show a transient increase after marathon running. The aim of this study was to investigate whether running duration influences the patterns of changes in cardiac biomarkers.

METHODS

Twenty participants with fast and slow finishing times were included in the study. Blood samples were taken before the marathon race, immediately after, and 24 hours after the race. Samples were analyzed for NT-proBNP and cardiac troponin T concentration. Furthermore, a complete blood cell count was performed.

RESULTS

After the marathon race, the fast and slow runners showed similar changes of NT-proBNP and cardiac troponin T (ie, a transient increase). Curve estimation regression analysis showed a curvilinear relationship (quadratic model) between running times and NT-proBNP increments immediately after the race, with less of an increase in the very fast and the very slow runners (r2 = .359, P = .023). NT-proBNP increments immediately after the race were correlated to the decline 24 hours after the marathon (r = -.612, P = .004).

CONCLUSIONS

This study indicates that NT-proBNP release immediately after marathon running varies in a curvilinear fashion with running time. It is speculated that low NT-proBNP release is associated with training adaptation in most elite runners and the relatively low cardiac stress in the slowest (but experienced) runners. The combination of less adaptation and relatively large cardiac wall and metabolic stress may explain the highest NT-proBNP values in runners with average running times. In addition, NT-proBNP decrements 24 hours after the race depend primarily on the values reached after the marathon and not on running time.

Effect of racing on cardiac troponin I concentration and associations with cardiac rhythm disturbances in Standardbred racehorses

INTRODUCTION/OBJECTIVES

Accumulating evidence indicates intense exercise can be associated with myocardial damage. Investigating the impact of maximal effort on myocardium and exploring possible association of injury with rhythm disturbance requires a high-sensitivity cardiac troponin assay. The objectives of this study were: (1) to determine the effect of racing on serum cardiac troponin I (cTnI) in Standardbred horses using a high-sensitivity assay; (2) to determine the 99th percentile of cTnI in healthy horses and investigate the effect of demographic variables on cTnI prevailing pre-race in Standardbred horses using a validated high-sensitivity assay and a contemporary assay, and; (3) to explore associations between exercise-associated arrhythmia and cTnI concentration.

ANIMALS

Racehorses (n = 145).

MATERIALS AND METHODS

≤ 2 h pre-race, cTnI concentrations were measured in 158 race starts. Electrocardiogram (ECG) monitoring was applied during racing and race recovery and screened for complex ventricular arrhythmia. Associations between cTnI prevailing before racing concentration, age, sex, and gait were investigated. Demographic and performance variables were evaluated for associations with cTnI concentration post-race and rhythm disturbance.

RESULTS

Incidence of arrhythmia was 11.6% (16 horses). A significant increase in median (interquartile range) cTnI concentration of 1.36 (0.49-2.81) ng/L was found post-race (p < 0.0001). Serum cardiac troponin I (cTnI) concentration prevailing pre-race was positively associated with increasing age, and gait. Serum cardiac troponin I prevailing post-race was positively associated with concentration prevailing pre-race. Interaction between arrhythmia and finishing distanced revealed horses finishing distanced and experiencing arrhythmia displayed higher cTnI release than with the presence of either alone.

CONCLUSIONS

Racing increased cTnI concentration. Horses finishing distanced and also exhibiting arrhythmia may be experiencing myocardial compromise.

The acute effects of an ultramarathon on biventricular function and ventricular arrhythmias in master athletes

AIMS

Endurance sports practice has significantly increased over the last decades, with a growing proportion of participants older than 40 years. Although the benefits of moderate regular exercise are well known, concerns exist regarding the potential negative effects induced by extreme endurance sport. The aim of this study was to analyse the acute effects of an ultramarathon race on the electrocardiogram (ECG), biventricular function, and ventricular arrhythmias in a population of master athletes.

METHODS AND RESULTS

Master athletes participating in an ultramarathon (50 km, 600 m of elevation gain) with no history of heart disease were recruited. A single-lead ECG was recorded continuously from the day before to the end of the race. Echocardiography and 12-lead resting ECG were performed before and at the end of the race. The study sample consisted of 68 healthy non-professional master athletes. Compared with baseline, R-wave amplitude in V1 and QTc duration were higher after the race (P < 0.001). Exercise-induced isolated premature ventricular beats were observed in 7% of athletes; none showed non-sustained ventricular tachycardia before or during the race. Left ventricular ejection fraction, global longitudinal strain (GLS), and twisting did not significantly differ before and after the race. After the race, no significant differences were found in right ventricular inflow and outflow tract dimensions, fractional area change, s', and free wall GLS.

CONCLUSION 

In master endurance athletes running an ultra-marathon, exercise-induced ventricular dysfunction, or relevant ventricular arrhythmias was not detected. These results did not confirm the hypothesis of a detrimental acute effect of strenuous exercise on the heart.