Abstract
d: The foot racing disciplines include sprints, middle distances, and long distances, which vary in terms of intensities, duration of training, and metabolic demands. The aim of our study was to evaluate the differences in morpho-functional parameters describing cardiac remodeling in a large cohort of Olympic athletes practicing the different track subspecialties.Methods: We evaluated 140 track and field (52.1% males, mean age 26.3±4.3 years) Olympic athletes divided into
distances, and long distances, which vary in terms of intensities, duration of training, and metabolic demands. The aim of our study was to evaluate the differences in morpho-functional parameters describing cardiac remodeling in a large cohort of Olympic athletes practicing the different track subspecialties.Methods: We evaluated 140 track and field (52.1% males, mean age 26.3±4.3 years) Olympic athletes divided into four groups according to the distance performed: Group A (46, 32.9%): 100 and 200 mt; Group B (34, 24.3%): 400 mt; Group C (25, 17.9%): 800, 1500, and 3000 mt; Group D (35, 24.9%): 5000, 10,000 mt, and marathon distance. The athletes underwent a pre-participation screening, which included transthoracic echocardiography and exercise stress testing.Results: In Group A and in Group B, most athletes presented normal cardiac geometry (41/46, 89.1% in Group A and 31/34, 91.2% in Group B,p< 0.0001). Instead, in Groups C and D, more than half presented eccentric cardiac remodeling (13\25, 52% in Group C and 23\35, 65.7% in Group D). No significant differences were found between subspecialties in LVEF (p= 0.587), diastolic function (p= 0.431), and training hours/week (p= 0.078). Conclusions: In conclusion, the presence and extent of cardiac remodeling vary according to the distance of the discipline practiced, with the largest dimensional increase in both left and right ventricles and atria in mid- and long-distance runners and the lowest in sprinters. Keywords:athletics; athlete’s heart; cardiac remodeling; Olympic; echocardiography; foot racing; sprints; exercise intensity; metabolic demands 1. Introduction Intense and prolonged physical exercise leads to a specific adaptation of the heart commonly known as “athlete’s heart” [1]. Differences in cardiac remodeling have been observed depending on the type of exercise training. Specifically, it has been reported that dynamic exercise leads to increased stroke volume, decreased vascular resistance, and enlargement of the heart chambers, refs. [2–8]. Conversely, static exercise results in increased transient blood pressure and is characterized by minimum thickening of the left J. Clin. Med.2024,13, 6027.
and enlargement of the heart chambers, refs. [2–8]. Conversely, static exercise results in increased transient blood pressure and is characterized by minimum thickening of the left J. Clin. Med.2024,13, 6027.
J. Clin. Med.2024,13, 6027 2 of 11 ventricular (LV) wall without an accompanying increase in cavity dimensions [9,10]. This concept, known as the “Morganroth hypothesis”, describes distinct cardiac adaptations that occur in response to different types of training (endurance vs. resistance) [11]. While it has been a foundational concept in exercise physiology, the recent literature suggests that these adaptations are more gradual and nuanced than originally proposed [12]. Track and field is a sport that includes different contests based on running, jumping, and throwing skills with a wide range of hemodynamic loads and functional demands [13]. The foot racing disciplines include sprints (100, 200, and 400 m), middle distances (800, 1500, and 3000 m), and long distances (5000, 10,000 m, and marathon), which vary in terms of intensities, duration of training, and metabolic demands. Indeed, power disciplines (100, 200, and 400 m) primarily rely on the anaerobic energy system (both the anaerobic lactic and anaerobic lactic systems). In fact, these disciplines depend mainly on creatine phosphate and muscle glycogen as fuel for energy production with minimal oxygen use [14,15]. So, power athletes develop muscular strength, hypertrophy, and neuromuscular efficiency to generate maximum force in minimal time. In contrast, endurance disciplines such as middle distances and long distances predominantly rely on the aerobic energy system, which provides a sustained energy supply for prolonged activities depending largely on carbohydrates and fats as energy substrates. Endurance athletes develop a high level of aerobic capacity (VO2 max), which is the body’s ability to efficiently transport and utilize oxygen during prolonged activity, leading to improved cardiovascular and respiratory efficiency [16]. Both types of sports impose very different demands on the body, leading to specialized adaptations in terms of energy systems, muscle function, and recovery needs [14,17]. The aim of our study was to evaluate the differences in morpho-functional parameters describing cardiac remodeling in a large cohort of Olympic athletes practicing the different track subspecialties. 2. Materials and Methods The Institute of Sport Medicine and Science in Rome functions as the medical division under the supervision of the Italian National Olympic Committee (CONI). Its primary objective
[14,17]. The aim of our study was to evaluate the differences in morpho-functional parameters describing cardiac remodeling in a large cohort of Olympic athletes practicing the different track subspecialties. 2. Materials and Methods The Institute of Sport Medicine and Science in Rome functions as the medical division under the supervision of the Italian National Olympic Committee (CONI). Its primary objective is to carry out medical evaluations for athletes chosen to compete in prestigious events such as the Olympic Games, World Championships, and Mediterranean Games. The research methodology employed in this investigation underwent scrutiny and approval by the Review Board of the Institute of Medicine and Sports Science, date of approval 20 February 2023, approval code CNI200223f. All athletes participating in this study were fully informed about the nature and scope of the evaluation and gave their informed consent in accordance with Italian law and institutional protocols. The clinical data from this cohort are securely stored in an institutional database. The activities detailed herein were conducted in accordance with the Code of Ethics of the World Medical Association (Declaration of Helsinki). We enrolled retrospectively 140 Olympic athletes practicing athletics (running) who participated at the London 2012, Rio 2016 and Tokyo 2020 Summer Olympic Games. The athletes participated in an extensive, multidisciplinary pre-participation assess- ment that involved a thorough clinical examination, resting electrocardiography (ECG), transthoracic echocardiography (TTE), and a maximal exercise stress test. Athletes who have arterial hypertension, diabetes (both type 1 and type 2), and/or cardiovascular structural or functional abnormalities were excluded. Athletes were arbitrarily divided into 4 groups according to the main distance per- formed: Group A: 100 mt and 200 mt; Group B: 400 mt; Group C: 800 mt, 1500 mt, and 3000 mt; Group C: 5000 mt, 10,000 mt, and marathon distance. Blood pressure was measured in the seated position prior to the exercise test, following the recommended guidelines [18]. Body height and weight were obtained in each subject, and body mass index (BMI) was calculated as weight (kg)\height (m 2 ). Body surface area (BSA) was derived by the
mt, and marathon distance. Blood pressure was measured in the seated position prior to the exercise test, following the recommended guidelines [18]. Body height and weight were obtained in each subject, and body mass index (BMI) was calculated as weight (kg)\height (m 2 ). Body surface area (BSA) was derived by the
J. Clin. Med.2024,13, 6027 3 of 11 Mosteller formula [19]. Body composition and fat mass percentage were measured using bioelectric impedance analysis (BIA 101 Quantum, Akern, Italy) using constant sinusoidal current at an intensity of 50 kHz and 400µA. Standard 12-lead ECG was performed in a supine position, and interpretations were made according to the international criteria for ECG interpretation in athletes [20]. All participants underwent maximal exercise testing on a bicycle ergometer (CubestressXR400; Cardioline S.p.A., Milan, Italy) as previously reported, with an incremental protocol until exhaustion. 2.1. Transthoracic Echocardiogram The echocardiographic assessment was performed on athletes in a resting state, set in the left lateral decubitus orientation. Ultrasound data acquisition was performed utilizing a GE Vivid E9 ultrasound system equipped with a 4Vc phased array probe (GE Healthcare Vingmed Ultrasound AS, Horten, Norway). A comprehensive 2D echocardiographic study was carried out, wherein cardiac images were captured in various cross-sectional planes employing established transducer positions. According to current recommendations [21], measurements of LV end-diastolic diameter (LVEDD), left ventricle end-systolic diameter (LVESD), interventricular septum (IVS) thickness, and PWT (posterior wall thickness) were taken in the parasternal short- axis section of the LV. The relative wall thickness (RWT) was calculated using the ratio of (IVS + PWT) to LVEDD [21]. LV mass (LVM) was derived using the Devereux for- mula [22], with measurements indexed to body surface area (BSA) [23]. An LVM indexed (LVMi) > 115 g/m 2 for males and >95 g/m 2 for females was indicative of LV hypertro- phy [23]. Different types of LV remodeling [21] were defined based on the measurements ob- tained, including normal geometry (NG), defined as LVM≤115 g/m 2 in males or≤95 g/m 2 in females and RWT≤0.42; concentric remodeling (CR), as LVM≤115 g/m 2 in males or ≤95 g/m 2 in females and RWT > 0.42; concentric hypertrophy (CH), as LVM > 115 g/m 2 in males or >95 g/m 2 in females and RWT > 0.42; and eccentric remodeling (ER), as LVM > 115 g/m 2 in males or >95 g/m 2 in females and RWT≤0.42. LV systolic function was assessed based on
in males or ≤95 g/m 2 in females and RWT > 0.42; concentric hypertrophy (CH), as LVM > 115 g/m 2 in males or >95 g/m 2 in females and RWT > 0.42; and eccentric remodeling (ER), as LVM > 115 g/m 2 in males or >95 g/m 2 in females and RWT≤0.42. LV systolic function was assessed based on LV ejection fraction (EF), derived from LV end-diastolic volume (LVEDV) and end-systolic volume (LVESV) computed through LV biplane planimetry employing the modified Simpson’s rule in both the apical 2- and 4-chamber views [23]. Diastolic function was evaluated using both pulsed-wave Doppler (PW) and tissue Doppler imaging (TDI) as recommended [24], based on the measurement of maximum blood flow velocities (Vmax) of E- and A-wave, E/A-ratio, as well as myocardial Vmax of e ′ and a ′ at the basal septal and lateral tricuspid annulus, along with the septal E/e ′ -ratio [24]. Left atrial (LA) volume was determined using the biplane method. The right ventricular (RV) chamber was evaluated in accordance with established guidelines [6]. The right atrial (RA) area and right ventricular (RV) function parameters were assessed using the RV-focused apical four-chamber view. The endocardial contour of the end-diastolic and systolic areas was traced, and from these measurements, the fractional area change (FAC) was calculated and expressed as a percentage [6]. Tricuspid annular plane systolic excursion (TAPSE) was measured as an indicator of RV longitudinal systolic function [6]. Peak tricuspid regurgitant velocity and the systolic trans-tricuspid gradient were assessed using continuous wave Doppler on the tricuspid regurgitation jet. Pulmonary artery systolic pressure (PASP) was calculated by adding the systolic trans-tricuspid gradient to the value of right atrial pressure (RAP). The latter was estimated using the inferior vena cava (IVC) dimension, inspiratory collapsibility, and RV function [6]. In all athletes, three consecutive cardiac cycles were assessed in accordance with the current literature [25]. All echocardiographic measurements were conducted by skilled sports cardiologists (GDG and AP). Between 2012 and 2016, only one expert sports cardiologist (AP) performed the echocardiograms. From 2016 to 2022, a second physician (GDG) joined the team and
dimension, inspiratory collapsibility, and RV function [6]. In all athletes, three consecutive cardiac cycles were assessed in accordance with the current literature [25]. All echocardiographic measurements were conducted by skilled sports cardiologists (GDG and AP). Between 2012 and 2016, only one expert sports cardiologist (AP) performed the echocardiograms. From 2016 to 2022, a second physician (GDG) joined the team and began conducting echocardiograms. Nevertheless, all reports were re-evaluated by AP prior to validation.
J. Clin. Med.2024,13, 6027 4 of 11 Intra-observer and inter-observer variability was assessed. Two investigators (GDG and AP), blinded, measured the same exam. Both investigators repeated the analysis two days later, without knowledge of the previous measurements. The interclass correlation co- efficients (ICCs) for LVEF were 0.91 for intra-observer and 0.92 for inter-observer agreement; for LVEDD, the ICCs were 0.93 for intra-observer and 0.92 for inter-observer agreement; for IVS thickness, the ICCs were 0.94 for intra-observer and 0.93 for inter-observer agreement; for LVEDV, the ICCs were 0.90 for intra-observer and 0.89 for inter-observer agreement. Discrepancies among observers were resolved through consensus. 2.2. Statistical Analysis Categorical variables were reported as frequencies and percentages and analyzed using either Fisher’s exact test or the Chi-square test, depending on the situation. For continuous variables, normality was assessed, and results were presented as means with standard deviations (SDs), with comparisons made using the Student’st-test for indepen- dent samples if the data followed a normal distribution. Pearson’s correlation coefficient was utilized for correlation analyses. A significance level ofp< 0.05 was applied to all tests. Intraclass correlation coefficients (ICCs) were calculated to evaluate both inter-observer and intra-observer agreement regarding the primary left ventricle measurements. The statistical analysis was conducted using STATA Statistics for Windows (SE, version 17). 3. Results Of the enrolled 140 athletes, 73 were males (52.1%), with a mean age of 26.3±4.3 years and a mean BMI of 20.4±2.6 kg/m 2 . Based on the type of discipline, we classified 46 athletes (32.9%) into a 100 mt and 200 mt group (Group A), 34 athletes (24.3%) into a 400 mt group (Group B), 25 athletes (17.9%) into an 800 mt, 1500 mt, and 3000 mt group (Group C), and 35 athletes (24.9%) into a 5000 mt, 10,000 mt, and marathon distance group (Group D). In Table, clinical and anthropometric parameters in different disciplines are listed. No significant gender differences were present, with a similar prevalence of male athletes (p= 0.511). Athletes performing long distance running (5000, 10,000, and marathons) were older (29±5.1) compared to other groups (24.8±3.6 years old in Group A, 25.6±3.7 years old
mt, 10,000 mt, and marathon distance group (Group D). In Table, clinical and anthropometric parameters in different disciplines are listed. No significant gender differences were present, with a similar prevalence of male athletes (p= 0.511). Athletes performing long distance running (5000, 10,000, and marathons) were older (29±5.1) compared to other groups (24.8±3.6 years old in Group A, 25.6±3.7 years old in Group B, and 26±3.4 years old in Group C;p< 0.0001). Other differences were found in anthropometric characteristics, with a progressive reduction in body weight (p< 0.0001), BMI (p< 0.0001), and BSA (p< 0.0001) from Group A (sprinters) to Group D (long-distance runners). Table 1.Clinical, anthropometric, and demographic characteristics in different disciplines. N = 140 100–200 mt 400 mt 800–1500–3000 mt5000–10,000 mt–Marathon N, (%) 46 (32.9) 34 (24.3) 25 (17.9) 35 (25) Male, n (%) 26 (56.5) 14 (41.8) 13 (52) 20 (57.1) 0.511 Age, years 24.8±3.6 25.6±3.7 26±3.4 29±5.1 0.0001 Afro-Caribbean, n (%) 12 (26.1) 6 (17.6) 8 (32) 6 (17.1) 0.459 Familiarity for CVD, n (%)9 (19.6) 6 (17.6) 2 (8) 9 (25.7) 0.388 Weight, kg 69.8±11.5 64.3±10.8 58.9±9.3 55.9±9.3 <0.0001 BSA 1.83±0.20 1.76±0.18 1.66±0.18 1.63±0.17 <0.0001 BMI, kg/m 2 21.9±3.1 20.7±2.2 19.5±1.5 19±1.8 <0.0001 Fat mass, % 11.4±4.9 12.1±4.4 12±4.8 10.8±4.9 0.677 Training hours per week 19.3±6.2 18±5.2 19.1±5.7 22.6±7.5 0.078 BMI: body mass index; BSA: body surface area; CVD: cardiovascular disease. Peculiar differences in echocardiographic measurements are highlighted (Table). A cardiac remodeling was observed, with multiparametric significant differences evident from Group A to Group D, including chamber size enlargement (both linear dimensions and volumes) of both ventricles and atria: i.e., LVEDD indexed (LVEDDi) (ranging from
J. Clin. Med.2024,13, 6027 5 of 11 27.3±2 mm/m 2 in Group A to 32.5±2.3 mm/m 2 in Group D),p< 0.0001; LVESD indexed (LVSEDi) (from 17.2±1.9 mm/m 2 in Group A to 19.5±2.1 mm/m 2 in Group D),p< 0.0001; LVEDV indexed (LVEDVi) (from 59±13.1 mL/m 2 in Group A to 81.5±16.3 mL/m 2 in Group D); IVS thickness (ranging from 9.3±1 mm in Group A to 9.6±1.1 mm in Group D),p= 0.008; PWT (from 8.7±1 mm in Group A to 9.3±1 mm in Group D),p= 0.003; LVM indexed (from 86.3±16.2 g/m 2 in Group A to 113.8±19.2 g/m 2 in Group D),p< 0.0001; LAV indexed (LAVi) (ranging from 18.1±6 mL/m 3 in Group A to 25.1±9.3 mL/m 3 in Group D),p< 0.0001; and RVOT indexes (RVOTi) LAX (p< 0.0001), RVOT indexed (RVOTi) SAX (p< 0.0001), and right area (RA) (p= 0.003), Figure. No significant differences, instead, were observed among groups regarding indexes of systolic function (p= 0.587) and diastolic function (E/E’,p= 0.431). Table 2.Echocardiographic differences in athletes practicing different athletic disciplines. N = 140 100–200 mt 400 mt 800–1500–3000 mt5000–10,000 mt–Marathon N, (%) 46 (32.9) 34 (24.3) 25 (17.9) 35 (25) LVEDDi, mm/m 2 27.3±2 28.9±1.8 31.4±2.6 32.5±2.3 <0.0001 LVESDi, mm/m 2 17.2±1.9 17.8±1.5 19.7±1.9 19.5±2.1 <0.0001 LVEDVi, mL/m 2 59±13.1 66.6±19.1 75.6±15.1 81.5±16.3 <0.0001 LVESVi, mL/m 2 21.4±6.4 23.8±8.7 26.7±6.1 28.1±8 0.0008 IVS, mm 9.3±1 8.9±1.1 9.6±0.8 9.6±1.1 0.008 PWT, mm 8.7±1 8.6±1 9.3±0.9 9.3±1 0.003 LVMi, g/m 2 86.3±16.2 88.1±14.3 108.9±16.1 113.8±19.2 <0.0001 EF, % 64.3±5.6 64.6±6.1 63.9±4.9 65.8±5.4 0.587 LAD, mm 32.9±3.5 33.5±3.6 35.6±3.4 36.3±3.3 <0.0001 LAVi, mL/m 3 18.1±6 17±3.1 22.4±5.4 25.1±9.3 <0.0001 AR, mm 29.1±3.5 29.1±3.5 29.2±3.3 29.6±2.6 0.930 AA, mm 25.3±2.9 25.7±2 25.9±1.8 27.4±3.1 0.042 E wave, cm/sec 82.7±16.1 86.4±15.2 82.2±12.3 84.1±13.4 0.663 A wave, cm/sec 48.6±10.8 45.3±11.7 42.4±8.5 43.6±10.5 0.082 E/A 1.77±0.5 2.03±0.6 2±0.4 2.03±0.5 0.083 E’, m/sec 12.5±2.4 12.4±2.5 11.9±1.7 11.7±2.1 0.408 A’, m/sec 6.3±1.3 6.1±1 5.9±1.2 6.4±1.4 0.497 S’, m/sec 7.8±1.3 7.8±1.3 7.6±1.4 8.1±1.2 0.568 E/E’ 6.79±1.5 7.2±2 7±1.1 7.3±1.6 0.431 PASP, mmHg 22.2±3.2 23.1±3.4 21.1±4.7 24±4.9 0.049 TAPSE, mm 25.3±2.8 26.5±3 26.3±4 26.4±4.5 0.430 RVEDA, mm 2 21.1±5 22.3±5.3 24.2±6.4
Description
The research assesses cardiac adaptations in athletes based on their specific track and field events.