Christou GA; Pagourelias ED; Deligiannis AP; Kouidi EJ;

Frontiers in physiology [Front Physiol] 2021 Sep 03; Vol. 12, pp. 693733.
Date of Electronic Publication: 2021 Sep 03 (Print Publication: 2021).

Aim: We aimed to investigate the main anthropometric, cardiorespiratory and haematological factors that can determine marathon race performance in marathon runners.
Methods: Forty-five marathon runners (36 males, age: 42 ± 10 years) were examined during the training period for a marathon race. Assessment of training characteristics, anthropometric measurements, including height, body weight ( n = 45) and body fat percentage (BF%) ( n = 33), echocardiographic study ( n = 45), cardiopulmonary exercise testing using treadmill ergometer ( n = 33) and blood test ( n = 24) were performed. We evaluated the relationships of these measurements with the personal best marathon race time (MRT) within a time frame of one year before or after the evaluation of each athlete.
Results: The training age regarding long-distance running was 9 ± 7 years. Training volume was 70 (50-175) km/week. MRT was 4:02:53 ± 00:50:20 h. The MRT was positively associated with BF% ( r = 0.587, p = 0.001). Among echocardiographic parameters, MRT correlated negatively with right ventricular end-diastolic area (RVEDA) ( r = -0.716, p < 0.001). RVEDA was the only independent echocardiographic predictor of MRT. With regard to respiratory parameters, MRT correlated negatively with maximum minute ventilation indexed to body surface area (VEmax/BSA) ( r = -0.509, p = 0.003). Among parameters of blood test, MRT correlated negatively with haemoglobin concentration ( r = -0.471, p = 0.027) and estimated haemoglobin mass (Hbmass) ( r = -0.680, p = 0.002). After performing multivariate linear regression analysis with MRT as dependent variable and BF% (standardised β = 0.501, p = 0.021), RVEDA (standardised β = -0.633, p = 0.003), VEmax/BSA (standardised β = 0.266, p = 0.303) and Hbmass (standardised β = -0.308, p = 0.066) as independent variables, only BF% and RVEDA were significant independent predictors of MRT (adjusted R ² = 0.796, p < 0.001 for the model).
Conclusions: The main physiological determinants of better marathon performance appear to be low BF% and RV enlargement. Upregulation of both maximum minute ventilation during exercise and haemoglobin mass may have a weaker effect to enhance marathon performance.