The Validity of an Updated Metabolic Power Algorithm Based upon di Prampero's Theoretical Model in Elite Soccer Players

• Published in: International journal of environmental research and public health 2020-12, Vol.17 (24), p.9554
• Main Authors: Savoia, Cristian, Padulo, Johnny, Colli, Roberto, Marra, Emanuele, McRobert, Allistair, Chester, Neil, Azzone, Vito, Pullinger, Samuel A, Doran, Dominic A
• Format: Article
• Language: English
• Subjects: Algorithms; Anaerobic threshold; Bias; Consumption; Data collection; Energy; Exercise; Exercise Test; Fitness equipment; Global positioning systems; GPS; Heart rate; Humans; Kinematics; Male; Metabolism; Models, Theoretical; Oxygen Consumption; Physical fitness; Running; Soccer; Soccer - physiology; Statistical analysis; Variance analysis
• ISSN: 1660-4601; 1661-7827; 1660-4601
• DOI: 10.3390/ijerph17249554

The aim of this study was to update the metabolic power (MP) algorithm (PV˙O2, W·kg ) related to the kinematics data (P , W·kg ) in a soccer-specific performance model. For this aim, seventeen professional (Serie A) male soccer players (V˙O2max 55.7 ± 3.4 mL·min ·kg ) performed a 6 min run at 10.29 km·h to determine linear-running energy cost (C ). On a separate day, thirteen also performed an 8 min soccer-specific intermittent exercise protocol. For both procedures, a portable Cosmed K4b gas-analyzer and GPS (10 Hz) was used to assess the energy cost above resting (C). From this aim, the MP was estimated through a newly derived C equation (P ) and compared with both the commonly used (P ) equation and direct measurement (PV˙O2). Both P and P correlated with PV˙O2 (r = 0.66, < 0.05). Estimates of fixed bias were negligible (P = -0.80 W·kg and P = -1.59 W·kg ), and the bounds of the 95% CIs show that they were not statistically significant from 0. Proportional bias estimates were negligible (absolute differences from one being 0.03 W·kg for P and 0.01 W·kg for P ) and not statistically significant as both 95% CIs span 1. All variables were distributed around the line of unity and resulted in an under- or overestimation of P , while P routinely underestimated MP across ranges. Repeated-measures ANOVA showed differences over MP conditions ( = 16.929 and < 0.001). Following Bonferroni post hoc test significant differences regarding the MP between P and PV˙O2/P ( < 0.001) were established, while no differences were found between PV˙O2 and P ( = 0.853). The new approach showed it can help the coaches and the soccer trainers to better monitor external training load during the training seasons.