Abstract
round: ESC sports classification in 2020, based on cardiac morphological adaptations, may not fully reflect also the variations in functional parameters of athletes. This study aims to characterize CPET-derived physiological parameters in elite athletes according to the ESC classification and evaluate whether this morphological classification also corresponds to a functional categorization.Methods: Elite athletes underwent pre-participation screening before the 2023 European Games and 2024 Olympic Games. Athletes were classified into four categories (skill, power, mixed and endurance). CPET was performed on a cycle ergometer using a ramp protocol, with measurements of VO2max, heart rate, power output and ventilatory efficiency.Results: We enrolled 1033 athletes (46.8% females; mean 25.6±5.2 years old) engaged in skill (14.1%), power (33.2%), mixed (33.3%) and endurance (19.4%) disciplines. O2pulse showed an incremental significant increase (p<
classified into four categories (skill, power, mixed and endurance). CPET was performed on a cycle ergometer using a ramp protocol, with measurements of VO2max, heart rate, power output and ventilatory efficiency.Results: We enrolled 1033 athletes (46.8% females; mean 25.6±5.2 years old) engaged in skill (14.1%), power (33.2%), mixed (33.3%) and endurance (19.4%) disciplines. O2pulse showed an incremental significant increase (p< 0.0001) among sport categories (skill 14.9±3.8 mL/beat; power 17.5±4.6 mL/beat, mixed 19±4.3 mL/beat and endurance 22.7±5.8 mL/beat). The lowest . VO2 max was observed in skill disciplines (36.3±7.9 mL/min/kg) whilst endurance ones showed the highest values (52.4±9.7 mL/min/kg) (p< 0.0001). . VO2 max was higher in power compared to mixed (42±7.7 mL/min/kg vs. 40.5±5.8 mL/min/kg,p= 0.005) disciplines with an overlapping amount between some mixed and power disciplines. No differences were found for VE max (p= 0.075).Conclusions: Our study provided values of CPET parameters in elite athletes. Significant differences in CPET parameters were observed among different sports disciplines, with endurance athletes showing the highest absolute and relative values in all parameters. An overlap amount was noted between mixed and power categories, especially for relative maximal oxygen consumption. Keywords:sports cardiology; cardiopulmonary exercise test; sports medicine; elite athletes 1. Introduction Over time, sports classification has been based on physiologic characteristics of the exercise (i.e., dynamic, static) [1,2] until 2020, when the European Society of Cardiology J. Clin. Med.2025,14, 4655 https://doi.org/10.3390/jcm14134655
J. Clin. Med.2025,14, 4655 2 of 11 (ESC) guidelines on sports cardiology and exercise introduced a new sport classification, closer to cardiologists’ understanding, based on the presence and type of cardiac remod- eling, comprising four major classes of sports disciplines (i.e., skill, power, mixed and endurance) [3]. However, this classification does not account for the actual functional parameters of athletes, potentially limiting its applicability in sports medicine. Cardiopulmonary exercise testing (CPET) is a comprehensive tool to assess the inte- grated function of the cardiovascular, pulmonary, vascular and musculoskeletal systems during exercise. Its application extends from performance optimization in athletes to clinical evaluation of those with known or suspected cardiopulmonary conditions. While CPET is widely used in the general population, its application in elite athletes still remains less explored, particularly concerning different sports categories. Indeed, elite athletes exhibit distinct physiological adaptations depending on their specific sport, necessitating tailored assessment criteria [4,5]. This study aims to characterize key CPET-derived physiological parameters in elite athletes divided into different sports disciplines according to the current ESC classification and to assess whether the morphological classification proposed by the ESC also reflects a functional categorization which incorporates both morphological and functional aspects. 2. Materials and Methods The Institute of Sport Medicine and Science in Rome, affiliated with the Italian National Olympic Committee, is tasked with conducting medical evaluations of athletes selected for relevant and international competitions such as the Olympic, European and Mediterranean Games. The present study was approved by the Ethics Committee of Sapienza University of Rome and by the internal Review Board of the Institute of Sports Medicine and Science on 25 September 2024, with code 0851/2024. All athletes included in this study were fully informed of the types and nature of the evaluation and signed the consent form, pursuant to Italian Law. All clinical data assembled from the study population are maintained in an institutional database. These procedures comply with the World Medical Association’s Code of Ethics (Declaration of Helsinki). For this study, we enrolled 1033 elite (Olympic) athletes who were evaluated for pre- participation screening before the Krakow 2023 European Games and
and signed the consent form, pursuant to Italian Law. All clinical data assembled from the study population are maintained in an institutional database. These procedures comply with the World Medical Association’s Code of Ethics (Declaration of Helsinki). For this study, we enrolled 1033 elite (Olympic) athletes who were evaluated for pre- participation screening before the Krakow 2023 European Games and Paris 2024 Olympic Games. The athletes underwent a thorough, multidisciplinary pre-participation screening, which included a complete physical exam, extensive blood tests, basal electrocardiography (ECG), transthoracic echocardiography (TTE) and a cardiopulmonary exercise test (CPET). All athletes enrolled in our study were elite athletes and, according to the current guidelines, trained for more than 10 hours per week [3]. Athletes participated in 42 different disciplines, divided into skill, power, mixed and endurance categories according to European classification and previous studies [3,6–9]. For sports disciplines not categorized within the ESC classification, we used the COCIS Italian Guidelines [10] to classify them, and in case of a different classification of the same discipline between European and Italian Guidelines, priority was given to the ESC classification. Athletes participated in the following sports disciplines: Archery, skeet shooting, target shooting, golf, park and street skateboarding, equitation, table tennis and sailing were classified as skill disciplines. Moreover, weightlifting, diving, synchronized swimming, taekwondo, athletics (<800 mt), boxing, artistic gymnastics, judo, Greek–Roman wrestling, climbing, Muai Thai, surfing, swimming (<400 mt), kickboxing, karate and BMX and mountain biking were grouped into power disciplines. Then, volleyball, beach volleyball, basketball, rugby, water polo, fencing, tennis, paddle tennis, beach soccer, sporting dancing, rhythmic gymnastics and badminton were included in mixed disciplines,
J. Clin. Med.2025,14, 4655 3 of 11 and, finally, canoeing, rowing, marathon swimming, pentathlon, marathon running, cycling and triathlon were classified as endurance sports. Anthropometric measurements were obtained, with body composition and percentage of body fat determined utilizing bioelectric impedance analysis (BIA101 Quantum, Akern, Pisa, Italy) employing a constant sinusoidal current at a frequency of 50 kHz and an intensity of 400µA. Height and weight were recorded for each subject, and body mass index (BMI) was computed as weight (in kilograms) divided by height (in meters) squared. Body surface area (BSA) was calculated using the Mosteller formula [11]. A standard 12-lead ECG was conducted with the subject in a supine position, and in- terpretation was performed in accordance with international criteria for ECG interpretation in athletes [12]. Blood pressure was assessed via non-invasive brachial cuff measurement while in a supine position at rest, according to European Society of Cardiology guide- lines [13], concurrently with the acquisition of apical views by TTE, prior to the execution of CPET [13]. 2.1. Cardiopulmonary Exercise Test We conducted CPET on a cycle ergometer (COSMED, Rome, Italy). The protocol included a one-minute rest, a two-minute warm-up without any load and subsequent increments of 15-20-25-30 Watts with a ramp protocol, depending on gender and sports discipline, until exhaustion [14]. Continuous ECG monitoring and recording (Quark T12x, COSMED) was obtained during the warm-up, exercise and subsequent recovery period, which lasted for five minutes. Additionally, we utilized a breath-by-breath metabolimeter (Quark CPET; COSMED) to measure oxygen consumption and carbon dioxide production throughout the entire cardiopulmonary assessment. We recorded the following parameters at the peak: 1. . VO2in absolute (mL/min) and relative (mL/min/kg) values; 2. 3. 4. 2(mL/min); 5. 6. . VO2/HR). When reaching both the lactate threshold and respiratory compensation threshold, measurements were conducted for the following: 7. 8. . VO2(mL/min); 9. . VO2/watts). Moreover, VE/CO2was measured with the exclusion of the data beyond the ventila- tory compensation point. Lactate threshold was measured according to current guidelines. In particular, in our study, it is defined by the following events, all of which occur roughly simultaneously: the . VO2
respiratory compensation threshold, measurements were conducted for the following: 7. 8. . VO2(mL/min); 9. . VO2/watts). Moreover, VE/CO2was measured with the exclusion of the data beyond the ventila- tory compensation point. Lactate threshold was measured according to current guidelines. In particular, in our study, it is defined by the following events, all of which occur roughly simultaneously: the . VO2 at which VE/ . VO2 and PetO2reach a minimum and thereafter begin to rise consistently, coinciding with an unchanged VE/VCO2and PetCO2[15]. 2.2. Statistical Analysis Categorical variables were expressed as absolute numbers and percentages (shown in parentheses), and group comparisons were conducted using either Fisher’s exact test or the Chi-square test, depending on suitability. The distribution of continuous vari- ables was evaluated for normality; variables with normal distribution were presented as mean±standard deviation (SD). For between-group comparisons of normally distributed
J. Clin. Med.2025,14, 4655 4 of 11 continuous variables, independent-sample Student’st-tests were applied. When assessing differences across multiple groups, the Dunn test with pairwise comparisons was employed. Ap-value < 0.05was considered indicative of statistical significance. All analyses were conducted using SPSS software, version 29 (SPSS Inc., Chicago, IL, USA). 3. Results We enrolled 1033 elite athletes (Olympic and probable Olympic), 483 females (46.8%), with a mean age of 25.6±5.2 years old, mostly Caucasians (47 Afro-Caribbean, 4.5%) with a mean BMI of 23.2±2.9 kg/m 2 . Overall, 5 athletes (0.5%) had hypertension under chronic pharmacological treatment, 2 athletes (0.2%) had insulin-dependent type I diabetes, 87 (8.4%) were active smokers, 25 (2.4%) had familiarity with sudden cardiac death (SCD) and 338 (32.7%) had a family history of cardiovascular diseases (CVDs). Athletes participated in a wide range of sports disciplines (42) divided into four categories according to the 2020 ESC classification: skill, 146 (14.1%); power, 343 (33.2%); mixed, 344 (33.3%; and endurance, 200 (19.4%). In Table main sport categories. Athletes practicing power disciplines were younger compared to the remaining categories (p< 0.0001); a higher prevalence of Afro-Caribbean athletes (7.9%,p= 0.0008) compared to skill disciplines (100% Caucasians athletes) and to mixed sports (3.5%,p= 0.013) was observed. A similar prevalence of female athletes was found between the groups (p= 0.218) but significant anthropometric differences were noted with mixed-discipline athletes being the tallest population (p< 0.0001), with the highest body weight (p< 0.0001) and the highest BSA (p< 0.0001) compared to other sports disciplines. Moreover, a higher DBP at rest was found in this group (p= 0.0001). Significant differences were also found in smoking habits (p< 0.0001), with no endurance athletes having this attitude whereas the highest prevalence was found in 15.1% of the athletes practicing skill disciplines and 13.4% of the mixed group. At CPET, significant differences among sport categories were found in multiple parameters (Table). A list of functional parameters (rest HR, maximal Watt, Watt/kg and O2pulse and Watt and . VO2 at first lactate threshold) showed an incremental significant increase (p< 0.0001) proceeding from sports with less aerobic components (skills) to those with
skill disciplines and 13.4% of the mixed group. At CPET, significant differences among sport categories were found in multiple parameters (Table). A list of functional parameters (rest HR, maximal Watt, Watt/kg and O2pulse and Watt and . VO2 at first lactate threshold) showed an incremental significant increase (p< 0.0001) proceeding from sports with less aerobic components (skills) to those with maximal ones (endurance). For other functional parameters, a clear difference was noted for skill and endurance disciplines, but an overlap amount was noted between the mixed and power categories. In fact, athletes practicing mixed disciplines presented, for the following parameters, lower or similar data compared to power athletes. Specifically, METS peaks reached in exercise stress tests were higher in power (12±2.3 vs. 11.5±1.8 in mixed,p= 0.008) as well as . VO2 max (42±7.7 mL/min/kg vs. 40.5±5.8 mL/min/kg in mixed,p= 0.005). Moreover, no significant differences were found for VE max (100.9±28 L/min, vs. 104.7±27 L/min, p= 0.075), VT (2.58±1.6 L in power vs. 2.68±0.6 L in mixed,p= 0.307), Watts at second lactate threshold (205.4±66.7 in power vs. 212.9±76.7 in mixed,p= 0.191) and . VO2 at second lactate threshold (2564.1±752 mL/min in power vs. 2649.9±905.6 mL/min in mixed,p= 0.199). Therefore, in order to evaluate the influence of a single sport discipline on these functional parameters, we have analyzed the . VO2 max values in all disciplines (Table). As also graphically shown in Figure, a certain quote of heterogeneity exists in all sport categories. Globally, similar values of . VO2 max were found in power and mixed disciplines, with BMX and mountain cyclists presenting values more suitable to the endurance category, as sailing (in skill) had values similar to mixed\power.
J. Clin. Med.2025,14, 4655 5 of 11 Table 1.Demographic and clinical characteristics of the population according to sports discipline. Skill Power Mixed Endurance P Pooled P Pairwise N, (%) 146 (14.1) 343 (33.2) 344 (33.3) 200 (19.4) Age, years 26.4 ±8.5 24.3 ±4 26 ±5 26.4 ±3.9 <0.0001 P vs. M,p< 0.0001; P vs. E,p< 0.0001; S vs. P, p= 0.0003; S vs. M,p= 0.643; S vs. E,p= 0.973; M vs. E,p= 0.454. Female, (%) 61 (41.8) 170 (49.6) 167 (48.5) 85 (42.5) 0.218 - Afro-Caribbean, n (%) 0 (0) 27 (7.9) 12 (3.5) 8 (4) 0.0008 S vs. P,p= 0.0005; S vs. M,p= 0.020; S vs. E, p= 0.014; P vs. M,p= 0.013;P vs. E,p= 0.076; M vs. E,p= 0.760. Height, cm 173.7 ±8.7 173.6 ±9.8 180.7±11.9 177.7±10 <0.0001 S vs. M,p< 0.0001; S vs. E,p= 0.0001; P vs. M, p< 0.0001; P vs. E,p< 0.0001; M vs. E,p= 0.003; S vs. P,p= 0.927. Weight, kg 71.8 ±14.2 70.1 ±14.1 77.8 ±14.2 71.6 ±13.1 <0.0001 S vs. M,p< 0.0001; P vs. M,p< 0.0001; M vs. E, p< 0.0001;S vs. P,p= 0.236; S vs. E,p= 0.905; P vs. E, p= 0.228; BMI, kg/m 2 23.7±3.8 23.1 ±3.1 23.7 ±2.4 22.5 ±2.4 <0.0001 S vs. E,p= 0.005; P vs. M,p= 0.006; P vs. E, p= 0.018; M vs. E,p< 0.0001;S vs. P,p= 0.075; S vs. M,p= 0.968. BSA 1.85 ±0.21 1.82 ±0.22 1.96 ±0.24 1.87 ±0.22 <0.0001 S vs. M,p< 0.0001; P vs. M,p< 0.0001; P vs. E, p= 0.010; M vs. E,p< 0.0001;S vs. E,p= 0.284; S vs. P, p= 0.241. SBP, mmHg 114.5 ±9.7 114.3±10.7 115.8±9.5 114.4±10.1 0.180 - DBP, mmHg 69 ±7.3 69 ±7.6 71 ±7.2 69.2 ±7 0.0001 S vs. M,p= 0.013; P vs. M,p< 0.0001; M vs. E, p= 0.004; S vs. P,p= 0.346; S vs. E,p= 0.984; P vs. E,p= 0.296. Familiarity for CAD, n (%) 49 (33.6) 119 (34.7) 118 (34.3) 52 (26) 0.161 - Smokers, n (%) 22 (15.1) 19 (5.5) 46 (13.4) 0 (0) <0.0001 S vs. P,p= 0.0005; S vs. E,p< 0.0001; P vs. M, p= 0.0004; P vs. E,p= 0.0007;
vs. E, p= 0.004; S vs. P,p= 0.346; S vs. E,p= 0.984; P vs. E,p= 0.296. Familiarity for CAD, n (%) 49 (33.6) 119 (34.7) 118 (34.3) 52 (26) 0.161 - Smokers, n (%) 22 (15.1) 19 (5.5) 46 (13.4) 0 (0) <0.0001 S vs. P,p= 0.0005; S vs. E,p< 0.0001; P vs. M, p= 0.0004; P vs. E,p= 0.0007; M vs. E,p< 0.0001; S vs. M,p= 0.620. Abbreviations: BMI: body mass index; BSA: body surface area; CAD: coronary artery disease; DBP: diastolic blood pressure; SBP: systolic blood pressure. Figure 1.Values of . VO2 max in mL/min/Kg according to practiced sports discipline, divided into skill (green), power (red), mixed (yellow) and endurance (blue) categories.
J. Clin. Med.2025,14, 4655 6 of 11 Table 2.Comparison of CPET parameters according to sports discipline. Skill Power Mixed Endurance P Pooled P Pairwise N, (%) 146 (14.1) 343 (33.2) 344 (33.3) 200 (19.4) Rest HR, bpm 63.8 ±11.1 58.3 ±10.6 56.8 ±9.2 52.1 ±10 <0.0001 P vs. M, p= 0.048; remainingp< 0.0001 Peak HR, bpm 173.9 ±12.5 169.4±12.1 166 ±12.1 166.1±13.1 <0.0001 S vs. P,p= 0.0002; S vs. M,p< 0.0001; S vs. E,p< 0.0001; P vs. M,p= 0.0002; P vs. E,p= 0.002; M vs. E,p= 0.921. MTHR, % 89.4 ±4.9 85.9 ±5.5 85.2 ±5.3 85.1 ±6.9 <0.0001 S vs. P,p< 0.0001; S vs. M,p< 0.0001; S vs. E,p< 0.0001; P vs. M,p= 0.078; P vs. E,p= 0.117; M vs. E,p= 0.817. Watt max 197.9 ±54.4 236.5±62.3 252.1±58.6 316.5±94.3 <0.0001 All p< 0.0001. Watt/Kg 2.79 ±0.7 3.39 ±0.8 3.23 ±0.5 4.42 ±1 <0.0001 All p< 0.0001. METs Peak 10.3 ±2.4 12 ±2.3 11.5 ±1.8 15.3 ±6.3 <0.0001 P vs. M, p= 0.008; remainingp< 0.0001 Peak SBP, mmHg 172.1 ±22 170.8 ±17.6 176.5±17.6 177.2±20.3 <0.0001 S vs. M,p= 0.021; S vs. E,p= 0.028; P vs. M,p< 0.0001; P vs. E,p= 0.0002; M vs. E,p= 0.672; S vs. P,p= 0.500. Peak DBP, mmHg 81.1 ±7.7 79.6 ±8.1 80.3 ±7.5 79.4 ±6.8 0.115 - . VO2max, mL/min/kg 36.3±7.9 42 ±7.7 40.5 ±5.8 52.4 ±9.7 <0.0001 P vs. M, p= 0.005; remainingp< 0.0001 . VO2/Watt 13.1±1.9 12.5 ±1.5 12.6 ±1.6 12.6 ±7 0.427 - VCO2, mL/min 2907.1±709.5 3219.3±839.53439±763.9 3980±989.3 <0.0001 P vs. M, p= 0.0004; remainingp< 0.0001. RQ 1.15 ±0.08 1.12 ±0.08 1.11 ±0.07 1.08 ±0.08 <0.0001 P vs. M, p= 0.231; remainingp< 0.0001. O2pulse, mL/beat 14.9 ±3.8 17.5 ±4.6 19 ±4.3 22.7 ±5.8 <0.0001 All p< 0.0001 VE max, L/min 90.7 ±20.7 100.9 ±28 104.7 ±27 121.3 ±33.7 <0.0001 P vs. M, p= 0.075; remainingp< 0.0001. VT, L 2.41 ±0.6 2.58 ±1.6 2.68 ±0.6 2.82 ±0.7 <0.0001 S vs. M,p< 0.0001; S vs. E,p< 0.0001; M vs. E,p< 0.0001; P vs. M,p= 0.307; S vs. P,p= 0.225; P vs. E,p= 0.053. Watt @ LT1 104.1 ±41 125.2 ±47 134.2 ±43.2 203.2±93.6 <0.0001 All
±28 104.7 ±27 121.3 ±33.7 <0.0001 P vs. M, p= 0.075; remainingp< 0.0001. VT, L 2.41 ±0.6 2.58 ±1.6 2.68 ±0.6 2.82 ±0.7 <0.0001 S vs. M,p< 0.0001; S vs. E,p< 0.0001; M vs. E,p< 0.0001; P vs. M,p= 0.307; S vs. P,p= 0.225; P vs. E,p= 0.053. Watt @ LT1 104.1 ±41 125.2 ±47 134.2 ±43.2 203.2±93.6 <0.0001 All p< 0.0001 . VO2@ LT1 1543.1±484.81756±533.1 1869.5±505.4 2563.3±978.6 <0.0001 P vs. M, p= 0.004; remainingp< 0.0001. VE/VCO2@ LT1 26.5 ±2.8 26.4 ±2.8 26.1 ±3.1 27 ±2.9 0.031 P vs. E,p= 0.018; M vs. E,p= 0.005; S vs. P,p= 0.664; S vs. M,p= 0.334; S vs. E,p= 0.130; P vs. M,p= 0.463. Watt @ LT2 168.9 ±56.2 205.4±66.7 212.9±76.7 275.4±103.7 <0.0001 P vs. M, p= 0.191; remainingp< 0.0001. . VO2@ LT2 2279±1066.82564.1±752 2649.9±905.6 3248.5±1070.2<0.0001 S vs. P,p= 0.001; S vs. M,p= 0.0002; S vs. E,p< 0.0001; P vs. M,p= 0.199; P vs. E,p< 0.0001; M vs. E,p< 0.0001. VE/VCO2@ LT2 27.6 ±3.3 27.7 ±3.2 27 ±3.2 27.9 ±3.4 0.014 P vs. M,p= 0.007; M vs. E,p= 0.006; S vs. P,p= 0.637; S vs. M,p= 0.103; S vs. E,p= 0.366; P vs. E,p= 0.534. Abbreviations: DBP: diastolic blood pressure; HR: heart rate; LT1: first lactate threshold; LT2: second lactate threshold; MET: metabolic equivalent of task; MTHR: maximal theoretical heart rate; RQ: respiratory quotient; SBP: systolic blood pressure; VE: ventilation; VE/VCO2: ventilatory efficiency; VT: tidal volume. Table 3. . VO2 max values in specific sports disciplines divided according to 2020 ESC/COCIS classification. Sport Category Sport Discipline N, (%) . VO2max, mL/min/Kg Skill 146 (14.1%) Archery 15 (10.3) 30.1±4.9 Skeet shooting 29 (19.9) 33±11 Target shooting 19 (13) 34.4±5.9 Golf 43 (29.4) 37±5.9 Park and street skateboarding 5 (3.4) 38.4±9 Equitation 18 (12.3) 39.5±3.9 Table tennis 5 (3.4) 41.8±5.2 Sailing 12 (8.2) 44.5±5.6 Power 343 (33.2%) Weightlifting 7 (2) 35.6±5.8 Diving 16 (4.7) 36.6±4.8 Synchronized swimming 19 (5.5) 37.2±3.1 Taekwondo 13 (3.8) 39.2±6.8 Athletics (<800 mt) 67 (19.5) 40±6.5 Boxing 20 (5.8) 41±6.5 Artistic gymnastics 24 (7) 41.1±4.3 Judo 32 (9.3) 41.3±6.4 Greek–Roman wrestling 21 (6.1) 41.4±6.0 Climbing 20 (5.8) 42.2±6.6 Muai Thai 4
Description
The study analyzes CPET parameters in elite athletes across different sports disciplines.