DEFD - Artículos

Road to Olympics: Modelling performance standards of those athletes classified for Paris 2024 in 1500m, 5000m, 10,000mand marathon

Road to Olympics: Modelling performance standards of those athletes classified for Paris 2024 in 1500m, 5000m, 10,000mand marathon Ruiz Alías, Santiago Alejo; García Pinillos, Felipe Elite athlete cohorts are complex and difficult to physiologically characterize using traditional approaches. Large-scale mathematical modelling of the speed-duration relationship offers a practical solution to describe and integrate physiological performance determinants across elite endurance athletes. Therefore, this study aims to describe the performance indices (i.e., critical speed [CS], work over critical speed [D′ ], maximal aerobic speed [MAS)] and the endurance index [EI]), of men and women athletes classified for Paris 2024 in 1500 m, 5000 m, 10,000 m, and the marathon. The start lists of Paris 2024 were retrieved from the World Athletics webpage. A total of 211 men and 234 women athletes were classified. Their historical best performances from 1500m to Marathon were noted from their profiles. The linear CS and Peronnet models were used to analyse their speed-duration relationship and retrieve different performance indices (i.e., CS, D′ , MAS and EI). The 5000m and 10,000mCSwere over 1500mand marathon (Men: P< 0.001;Women: P< 0.001). 1500m athletes were characterized by a superior D′ in both sexes (P< 0.001), being of similar size among the rest of the events. Marathon athletes were characterized by the lowest MAS in both sexes (P< 0.001), remaining similar among the rest of the events. The EI was proportional to the distance of each event, being the EI of marathon the lowest (Men:4.5%; Women:4.1%). These performance indices serve as a benchmark for elite performance in middle- and long-distance events, emphasizing the specific demands of each race distance.

Sleep Efficiency Predicts Next-Day Glycaemia and Daytime Glycaemia Influences Sleep in Free-Living Adults at Risk of Type 2 Diabetes

Sleep Efficiency Predicts Next-Day Glycaemia and Daytime Glycaemia Influences Sleep in Free-Living Adults at Risk of Type 2 Diabetes Clavero-Jimeno, Antonio; Martín Olmedo, Juan José; Hidalgo Migueles, Jairo; Camacho Cardeñosa, Alba; Molina Fernández, Marcos; Dote Montero, Manuel; Merino, Jordi; Muñoz Torres, Manuel Eduardo; Labayen, Idoia; Ruiz Ruiz, Jonatan Aim: To investigate how sleep features influence next-day diurnal glucose homeostasis and vice versa in free-living adults at risk of type 2 diabetes. Materials and Methods: This observational repeated-measures study included 388 adults aged 25–65 years (50% women) with overweight or obesity (BMI ≥ 25.0–< 40.0 kg/m2). Sleep and glucose homeostasis were simultaneously assessed over 14 days using wrist-worn accelerometers and continuous glucose monitors. Linear mixed models evaluated day-level associations between sleep metrics—wake-up time, sleep period time (i.e., time from sleep onset to wake-up) and sleep efficiency ([total sleep time/sleep period time] × 100)—and diurnal glucose metrics, including mean glucose and its standard deviation (glycaemic variability). Results: We analysed 3942 valid person-days. Each 1% increase in sleep efficiency was associated with lower next-day mean glucose (B [95% CI] = −0.05 [−0.08, −0.01] mg/dL; p = 0.007). Each 1 h delay in wake-up time was linked to reduced next-day glucose variability (−0.24 [−0.38, −0.10] mg/dL; p = 0.001). Conversely, each 1 mg/dL increase in daytime mean glucose was associated with later wake-up time (0.008 [0.002, 0.014] h; p = 0.008), longer sleep period time (0.006 [0.000, 0.012] h; p = 0.039) and lower sleep efficiency (−0.05% [−0.08%, −0.01%] %; p = 0.005) the subsequent night. Each 1 mg/dL increase in glucose variability was associated with earlier wake-up time (−0.02 [−0.03, −0.01] h; p < 0.001). Conclusions: This study provides evidence that sleep and glucose dynamics are temporally associated in free-living adults at risk of type 2 diabetes. These findings underscore the potential of combining sleep and glucose metrics to inform cardiometabolic risk prevention strategies. This study (Project ref. PID2022.141506OB.I00) is funded by the MCIU/AEI/10.13039/501100011033 and by ERDF, EU a way of making Europe to J.R.R.; Junta de Andalucía, Consejería de Transformación económica, Industria, Conocimiento y Universidades (A-CTS-516-UGR20) to J.R.R.; the University of Granada Plan Propio de Investigación-Excellence actions: Unit of Excellence on Exercise Nutrition and Health (UCEENS) to J.R.R.; the Consejo Superior de Deportes, Ministerio de Cultura y Deporte, Plan de Recuperación, Transformación y Resiliencia, Funded by the European Union – NextGenerationEU (EXP_75091) to I.L.; the Government of Navarra, Departamento de Desarrollo Economico y Empresarial (0011-1365-2021-00070), Plan de Promoción de Grupos de Investigación de la Universidad Pública de Navarra to I.L.; Spanish Ministry of Universities (FPU21/01161 to A.C.-J., FPU22/01631 to J.J.M.-O., FPU23/02158 to M.M.-F., and FPU18/03357 to M.D.M). J.H.M. is supported by grant RYC2024-050453-I funded by MCIN/ AEI/10.13039/501100011033. A.C.-C. is supported by the Junta de Andalucía, Consejería de Salud y Consumo (RHJ-0098-2024). J.M. is supported by the Novo Nordisk Foundation grant NNF23SA0084103, the EFSD/Novo Nordisk Foundation Future Leaders Award (no. 0094134) and the European Union (HORIZONEIC-2023- PATHFINDERCHALLENGES-01-101161509). In addition, funding was provided from the EXERNET Research Network on Exercise and Health (DEP2005-00046/ACTI; 09/UPB/19; 45/UPB/20; 27/UPB/21 to I.L. and J.R.R.). Instituto de Salud Carlos III, MCIU/AES and by ERDF, EU a way of making Europe (PI24/01360). This work is part of a doctorate thesis conducted in the Official Doctoral Program in Biomedicine of the University of Granada, Spain. The funders had no role in the design, conduct or interpretation of the study.

Task Failure in Endurance Sports: A Review

Task Failure in Endurance Sports: A Review Pérez-Díaz, Juan-José; Salas-Montoro, José-Antonio; Hopker, James; Zabala, Mikel Task failure in endurance sports represents a complex and multifaceted phenomenon likely arising from the dynamic and intricate interaction between peripheral and central mechanisms. Traditional models of fatigue have long emphasized a gradual and inevitable decline in performance because of metabolic, neuromuscular, and cardiovascular limitations. Research has also highlighted that task failure may not only be a product of this progressive deterioration but could also result from acute and unpredictable disruptions at the central level (e.g., psychological factors such as perceived effort) that compromise the athlete’s ability to sustain effort. This review examines the existing literature on task failure, critically describing what is currently known about the influence of peripheral (physiological processes at the skeletal muscle and neuromuscular junction) and central mechanisms (neural processes in the brain and spinal cord, which may integrate physiological and psychological components). Finally, we identify gaps in the current literature and propose directions for future research to refine our understanding of the interplay between peripheral and central contributors to task failure, emphasizing the need for integrative approaches to optimize endurance performance.

Effects of Attentional Focus on Performance and Perceived Exertion during 400-meter races in University Students

Effects of Attentional Focus on Performance and Perceived Exertion during 400-meter races in University Students Pérez-Díaz, Juan-José; Sánchez-Muñoz, Cristóbal; Salas-Montoro, José-Antonio Attentional focus (internal/external) affects motor performance; its effect on performance (time) and perceived exertion (RPE) during 400m races was studied in non-expert university students, an area with limited research. The objective was to investigate the effects of internal vs. external focus on time and RPE in this task, considering gender differences. Using a counterbalanced repeated-measures design, 89 sports science students (37 women, 52 men) performed two 400m runs under internal focus (technical instructions) and external focus (outcome/competition instructions). Time and RPE (Borg CR10) were measured. Paired t-tests and mixed ANOVAs (2 Focus x 2 Gender) were used for analysis. Results showed no significant difference in time between focus conditions (p=0.054), although there was a pro-external tendency. RPE was significantly higher with external focus (p<.001). Men were faster (p<.001) with no significant gender differences in RPE (p=.572). Significant Focus x Gender interactions were found for time (p=.007) and RPE (p=.005). Simple effects analysis revealed that external focus significantly improved time in men (p<.001) but not in women (p=.548), while the RPE increase was significant for both genders but larger in men (p<.001) than in women (p=.008). In conclusion, in non-expert students, while the main effect of external focus on time was not significant, it did increase RPE. The effects of focus were moderated by gender. It is suggested to consider the performance-RPE balance and individual differences when applying focus strategies in this context.

Effect of Breast Cancer Surgery on Upper-Limb Muscle Activation

Effect of Breast Cancer Surgery on Upper-Limb Muscle Activation Franco-López, Francisco; Hernández-Belmonte, Alejandro; García Segura, Ana María; López Bueno, Jaime; Martínez-Cava, Alejandro; Courel Ibáñez, Javier; Pallarés, Jesús G. This two-step design used the unilateral bench press to examine the effect of breast cancer surgery on upper-limb muscle activation under low and moderate fatigue conditions. First, we studied the proper method to normalize the activation values obtained during dynamic contractions. For that, the muscle activation was relativized to the maximal value obtained during (i) an isometric contraction (ISONorm), and the concentric phase of the (ii) repetition maximum load (1RMNorm), and (iii) the first three repetitions of an 80% 1RM set (Max80%Norm). The normalization method with the lowest inter-subject variability was further used to compare the muscle activation of the affected and non-affected sides of twelve women who underwent unilateral breast surgery (eight mastectomies and four lumpectomies). Both sides were tested using dynamic sets at 60 and 80% of their 1RM until reaching 40% velocity loss (VL). Repetitions completed at each %1RM were then divided into two groups: low fatigue (first half of repetitions) and moderate fatigue (second half of repetitions). On results, the ISONorm and the Max80%Norm showed the highest (mean CV = 32.9%) and lowest (mean CV = 12.9%) inter-subject variability, respectively. The affected side showed higher activation for the deltoid and triceps (Δ = 6.9 to 15.9%) but lower for the pectoralis (Δ = −5.7 to −13.2%) against 60% 1RM. These differences were lower and without a consistent trend against 80% 1RM. Between-side comparisons were not significant for either 60% 1RM (p > 0.270) or 80% 1RM (p > 0.500). Although these results should be interpreted with caution due to the small and heterogeneous sample, our analyses did not reveal meaningful differences in upper-limb muscle activation following breast cancer surgery.