Relationships between Training Loads and Selected Blood Parameters in Professional Soccer Players during a 12-Day Sports Camp

Abstract

The main purpose of this study is to assess the relations between training loads and selected blood parameters in professional soccer players during a preseason sports camp. Fifteen professional soccer players (age: 24.3 ± 5.25 year; height: 182.6 ± 6.75 cm; weight: 76.4 ± 6.72 kg) participated in the 12-day training camp. All the training sessions and friendly games were accurately analyzed with a GPS system. Blood samples were taken from the players and analyzed before the camp (PRE), in the middle (MID), and one day after the camp (POST). Mean total distance covered by the players during the camp was 85,205 ± 2685 m, high-intensity running 12,454 ± 1873 m, and sprinting 639 ± 219 m. The highest aspartate transaminase (AST), lactate dehydrogenase (LDH), creatine kinase (CK), and C-reactive protein (CRP) values were observed after six days of the camp. The application of intensive training during a 12-day sports camp can be associated with chronic muscle pain with high activity of some blood enzymes (CK, AST) and a high concentration of myoglobin (Mb). During training camps longer than 10 days, it would be necessary to apply, every second or third day, one day of rest, and the training load should not exceed two units every day.

Blood Biomarkers Variations across the Pre-Season and Interactions with Training Load: A Study in Professional Soccer Players

“…The studies mentioned above support the results of our study. However, these results differ from the study published by Radzimiński et al [ 70 ], where it was found that elevated CRP values were not detected in soccer players during a pre-season sports camp (pre: 1.44 ± 0.7 mg/L, post: 0.83 ± 0.34 mg/L), i.e., above the reference range (<5.0 mg/L).…”

“…Increased levels of oxidative stress are closely associated with markers of muscle damage with high inflammation [ 59 ]. CRP is the most common inflammation molecule of the body’s acute phase response, and it increases the inflammatory response to various stimuli that initiate the acute phase response [ 47 , 69 , 70 ]. In our study, significant increases were found in CRP values after post-pre-season compared to pre-pre-season.…”

“…It was recently determined that decreases in CRP levels of futsal players, also asserted that reductions in the CRP level indicated that players adapt to the training load applied throughout the competitive season [ 59 ]. Radzimiński et al [ 70 ], emphasized that inflammation in the bodies of pre-season soccer players might be the result of misuse of high-intensity training loads in a short time. On the other hand, a previous study stated that GPS variables associated with high-intensity activities, such as running speeds, accelerations, and decelerations were useful markers for detecting muscle damage or inflammation [ 74 ].…”

Changes of 25(OH)D Concentration, Bone Resorption Markers and Physical Performance as an Effect of Sun Exposure, Supplementation of Vitamin D and Lockdown among Young Soccer Players during a One-Year Training Season

“…Due to the nature of professional soccer, players are at particular risk for vitamin D insufficiency. The reason for this is the large number of official matches played during the annual training cycle where the difference between the pre-season and competitive periods has become indistinct and the detraining period sometimes last less than two weeks [ 31 ]. The periodization was more widely observed and respected in training periods of young soccer players [ 31 ].…”

Marathon Running Increases Synthesis and Decreases Catabolism of Joint Cartilage Type II Collagen Accompanied by High-Energy Demands and an Inflamatory Reaction

“…Inflammatory biomarkers as C-reactive protein (CRP), an acute-phase inflammatory protein, and high-energy enzyme biomarkers as creatin kinase (CK), a high-energy phosphate enzyme, reportedly have a dose-dependent behaviour with a transient increase after a 24-h marathon and ultra-marathon (Kim et al, 2009). Lactate dehydrogenase (LDH) is a key glycolytic enzyme that increases with increased training loads (Radzimiński et al, 2020).…”