Variation in weekly internal training load in professional soccer players

Area of Science:

• Sports Science
• Exercise Physiology
• Soccer Performance Analysis

Background:

• Team-level weekly training load (w-TL) in professional soccer often lacks variation.
• Individual player responses to training load require deeper investigation.

Purpose of the Study:

• To analyze respiratory and muscular weekly perceived exertion in soccer players.
• To determine the variability of training load during pre-season and in-season periods on an individual player basis.

Main Methods:

• Monitored 21 professional soccer players over 44 weeks (6 pre-season, 38 in-season).
• Assessed internal load using differential Rating of Perceived Exertion (dRPE).
• Statistical analysis included descriptive statistics, coefficient of variation (CV), and Kruskal-Wallis test.

Main Results:

• Leg local-muscular weekly training load (w-TLmus) was significantly higher than central-respiratory weekly training load (w-TLres) in both periods.
• Total weekly loads were greater in pre-season than in-season.
• Intra-player variability in training load was significantly higher during pre-season (CV: 30.4–75.4% and 15.3–76.9%) compared to in-season (CV: 21.2–46.1% and 22.1–44.2%).

Conclusions:

• Soccer players perceive and respond to training loads differently across seasonal phases.
• Individualized monitoring of training load is essential for optimizing performance.
• Tailored training load management can help reduce injury risk in professional soccer players.