Effects of Task Specificity on External and Internal Load in Professional Male Futsal Players: A Prospective Observational Study.

BACKGROUND: Futsal is characterized by intermittent high-intensity actions that impose substantial external (EL) and internal (IL) load demands. Although load monitoring using accelerometry and perceptual measures is widely applied, the interaction between EL, IL, and wellness status across the competitive microcycle in elite futsal players, particularly regarding task specificity, remains unclear. The aims were to (1) analyze the effects of microcycle day and task specificity on EL, IL, and wellness status; and (2) examine the relationships between these variables.

HYPOTHESIS: Training sessions with higher task specificity would elicit greater EL, IL, and wellness disturbances, with match day (MD) presenting the highest load values.

METHODS: Ten professional futsal players (age, 25.4 ± 4.8 years) from the Spanish first division were monitored during 43 training sessions and 11 official matches. Variables included microcycle day, task specificity, EL measured by accelerations (≥2 m/s2) and decelerations (≤-2 m/s2), IL assessed using rating of perceived exertion (RPE), and wellness status evaluated through the Hooper index (HI), including delayed onset muscle soreness (DOMS), stress, fatigue, and sleep.

RESULTS: MD produced significantly higher EL and RPE values (P = 0.04 to P < 0.001) than most training sessions. Among training sessions, those conducted 3 days before MD (MD-3) exhibited the highest task specificity, EL, and RPE. Strong positive correlations were found between task specificity and EL (rho = 0.85; P < 0.001), task specificity and RPE (rho = 0.80; P < 0.001), task specificity and fatigue (rho = -0.45; P < 0.001), EL and RPE (rho = 0.80; P < 0.001), and EL and fatigue (rho = -0.30; P = 0.03).

CONCLUSION: Microcycle day and task specificity significantly influenced EL, IL, and fatigue during the competitive microcycle in professional futsal. Sessions with higher task specificity exhibited greater EL and IL, highlighting the importance of tailoring training tasks to modulate player load.

CLINICAL RELEVANCE: Accurate monitoring and management of training load enhances understanding of the relationship between training stimuli and players' adaptive responses, supporting performance optimization and informing strategies for injury prevention and rehabilitation.

STUDY DESIGN: Prospective observational study.

LEVEL OF EVIDENCE: Level 3.