Body Composition Interactions with Physical Fitness: A Cross-Sectional Study in Youth Soccer Players

Comparison of body composition and muscle mass by age in amateur soccer players

[Purpose] This study aimed to elucidate the changes in body composition components associated with aging in amateur male soccer players. Specifically, we investigated the alterations in the phase angle and regional muscle mass distribution. [Participants and Methods] The study included a cohort of 163 male participants categorized into three age groups: U15 (12-15 years), U18 (16-18 years), and O19 (≥19 years). Precise body composition assessments were performed, employing the InBodyS10 body composition scale. [Results] The findings revealed substantial age-related disparities in various body composition parameters. Data revealed a consistent trend of increasing basic body composition metrics with age. Notably, the body fat percentage progressively increased with age. Muscle mass and phase angle exhibited age-related increases with nuanced variations in different anatomical regions. [Conclusion] In the general Japanese population, muscle mass tends to decrease with age after 18 years. However, in this study on amateur soccer players, we observed a plateau in the height and lower limb phase angle around the age of 18 years, whereas muscle mass exhibited an increasing trend.

Lower limbs strength variations between injured and non-injured professional soccer players

Due to its physical demands, professional soccer is becoming a real challenge regarding players' exposure to high injury risk. Given its tight correlation with high-intensity actions, muscular strength is a crucial physical characteristic for soccer players. Therefore, the aims of this study are (a) to compare the vertical jumping performance during the season according to the injury profile, and (b) to investigate differences in isokinetic strength performance at the beginning and the end of the season. Twenty-one male professional soccer players (age: 26.0 ± 4.1 years, height: 181.0 ± 6.9 cm, body mass: 73.7 ± 6.9 kg) were assessed in isokinetic strength (Biodex System 4 Pro Dynamometer), and Optojump Next (Microgate, Bolzano, Italy). Isokinetic strength analyses considered the peak torque scores of knee flexors and knee extensors, according to the player's preferred and non-preferred limb. The countermovement and squat jump maximum height were assessed as lower body explosive strength indicators. No significant differences were found when comparing injured and non-injured players in vertical jump and isokinetic strength assessments. However, significant results were found when comparing both groups' initial and final evaluation in isokinetic strength assessment, with both groups significantly improving their performance. Our findings indicate that the overall lower body strength performance was not a discriminant factor between injured and non-injury players. Thus, muscular strength assessment performance increased throughout the season independently of the injury profile. Future research needs to integrate other variables related to sports injuries since they seem to result from multifactorial causes.

The Influence of Somatic Maturity on Anthropometrics and Body Composition in Youth Soccer Players

The primary aim of this investigation was to compare players' anthropometric (AP) and body composition (BC) characteristics between distinct maturity bands (pre-PHV, circa-PHV, post-PHV) in youth elite soccer. This study considered 320 male soccer players (mean age 13.8 y). Participants were from U14 (n = 157) and U15 (n = 163) age categories. The Khamis-Roche method was applied to calculate the percentage of predicted adult height (PAH) at the time of assessment based on which the players were further divided into maturity bands (pre-PHV ≤ 87%, circa-PHV = 88-95%, post-PHV > 95%). The findings indicated that most of the players were in the circa-PHV stage at the time of investigation. Measurements included height and weight. The estimates of BC parameters were derived using bioelectrical impedance (BIA) analysis. These various AP and BC attributes displayed significant differences among the maturity bands (F = 139.344-7.925; p < 0.001; large effect sizes) except in body fat mass (BFM) (F = 2.998; p = 0.051; small effect size). The current somatic maturity stage of the athletes should be considered when evaluating BC results, otherwise there is a risk of misinterpretation.

Differences in Kinanthropometric Variables and Physical Fitness of Adolescents with Different Adherence to the Mediterranean Diet and Weight Status: "Fat but Healthy Diet" Paradigm

The present investigation provides a new paradigm, the fat but healthy diet, through which to analyze the importance of adherence to the Mediterranean diet (AMD) in the adolescent population. To this end, the objectives were to analyze the existing differences in physical fitness, level of physical activity, and kinanthropometric variables in males and females with different AMD and to determine the existing differences in physical fitness, level of physical activity, and kinanthropometric variables in adolescents with different body mass index and AMD. The sample consisted of 791 adolescent males and females whose AMD, level of physical activity, kinanthropometric variables, and physical condition were measured. The results showed that when analyzing the whole sample, the differences were only significant in the level of physical activity among adolescents with different AMD. However, when considering the gender of the adolescents, the males also showed differences in the kinanthropometric variables, while the females did so in the fitness variables. In addition, when considering gender and body mass index, the results showed that overweight males with better AMD showed less physical activity and higher body mass, sum of three skinfolds, and waist circumference, and females did not show differences in any variable. Therefore, the benefits of AMD in anthropometric variables and physical fitness of adolescents are questioned, and the fat but healthy diet paradigm cannot be confirmed in the present research.

Using A-Mode Ultrasound to Assess the Body Composition of Soccer Players: A Comparative Study of Prediction Formulas

For elite athletes, monitoring body composition is important for maximizing performance without health risks. Amplitude (A)-mode ultrasound (AUS) has attracted increasing attention as an alternative to skinfold thickness measurements commonly used for assessing the amount of body fat in athletes. AUS accuracy and precision, however, depend on the formula used to predict body fat percentage (%BF) from subcutaneous fat layer thicknesses. Therefore, this study evaluates the accuracy of the 1-point biceps (B1), 9-sites Parrillo, 3-sites Jackson and Pollock (JP3), and 7-sites Jackson and Pollock (JP7) formulas. Relying on the previous validation of the JP3 formula in college-aged male athletes, we took AUS measurements in 54 professional soccer players (aged 22.9 ± 3.83 y, mean ± SD) and compared the results given by different formulas. The Kruskal-Wallis test indicated significant differences (p < 10^-6), and Conover's post hoc test revealed that the JP3 and JP7 data come from the same distribution, whereas the data given by B1 and P9 differ from all the others. Lin's concordance correlation coefficients for B1 vs. JP7, P9 vs. JP7, and JP3 vs. JP7 were 0.464, 0.341, and 0.909, respectively. The Bland-Altman analysis indicated mean differences of -0.5 %BF between JP3 and JP7, 4.7 %BF between P9 and JP7, and 3.1 %BF between B1 and JP7. This study suggests that JP7 and JP3 are equally valid, whereas P9 and B1 overestimate %BF in athletes.

Body composition variations between injured and non-injured professional soccer players

Professional soccer is characterized by its physical demands, making players' exposure to high injury risks a growing problem. It is crucial to study the factors associated with injuries in professional soccer. This study aimed to investigate the relationship between age, body composition, and others variables related with the injury profile of professional soccer players of a specific Portuguese team. Also, it analyzed the impact of the injury profile on soccer's variations in body fat (BF%), skeletal muscle mass (SMM) and total body water (TBW) throughout the season. The sample comprised 31 male professional soccer players competing in the First Portuguese Soccer League. Older players had a higher prevalence of muscular injuries. Midfielders and forwards showed the highest number of muscular injuries during the season being quadriceps the most affected zone. Considering players' BF% [Wilks' Lambda = 0.42, F (7, 23) = 4.61, p = 0.002, r = 0.58], SMM [Wilks' Lambda = 0.59, F (6, 23) = 2.70, p = 0.039, r = 0.41] and TBW [Wilks' Lambda = 0.54, F (7, 23) = 2.80, p = 0.029, r = 0.46] there was a substantial main effect for the assessments performed throughout the season and the injury status. Age assumes relevance in explaining the injury profile. The impact of the injury profile on soccer's variations in BF%, SMM and TBW throughout the season must be analyzed considering the clinical relevance.

Changes in body composition during the macrocycle of professional football players in relation to sports nutrition knowledge

Professional football players are obligated to meet the physical demands and maintain the best possible performance throughout the whole macrocycle. It is important to assess the players' nutrition knowledge, identify areas that require increased nutrition awareness and identify the impact of knowledge on changes in body composition as this can affect the players' health and performance. This study aimed to assess changes in the body composition of professional football players during the macrocycle of the spring round of the football championship and to identify the correlation between nutrition knowledge and maintaining body composition. The study included 38 football players. The players' body compositions were analyzed 6 times during the macrocycle consisting of preparatory, competitive, and transition periods using the Direct Segmental Multi-Frequency Bioelectrical Impedance Analysis method. Athletes completed the Nutrition for Sport Knowledge Questionnaire to assess their nutrition knowledge. During the preparatory period, a statistically significant negative correlation was demonstrated between the players' knowledge about the subsections of micronutrients in the diet and the dispersion of the adipose percentage tissue content (r = -0.36, p = 0.03). In the competitive period, there was a statistically significant negative correlation between the players' knowledge of sports nutrition and the dispersion of lean body mass (r = -0.46, p = 0.004), and skeletal muscle mass (r = -0.36, p = 0.03). During the transition period, a statistically significant negative correlation between the players' knowledge of weight control and the dispersion of body mass (r = -0.47, p = 0.00) and BMI values (r = -0.48, p = 0.00) was identified. The player's knowledge about the subsection of macronutrients significantly negatively correlated with the dispersion of skeletal muscle mass content (r = -0.33, p = 0.05). Nutrition knowledge has an impact on the stability of body composition during all analyzed periods: preparatory, competitive, and transition periods.

Physical Fitness Variations between Those Playing More and Those Playing Less Time in the Matches: A Case-Control Study in Youth Soccer Players

The purpose of this study was (i) to compare two groups (players with more vs. less match play time) regarding body composition, vertical and horizontal jumping performance, and aerobic capacity; and (ii) to test the relationships between physical fitness and play time. This study followed a case-control design in which the outcome was playtime, and the causal attribute was physical fitness. Sixty-six youth male soccer players from under-16 (n = 21), under-17 (n = 19), under-18 (n = 12), and under-19 (n = 14) age groups were monitored for match play time during five months of observation. Inclusion criteria consisted of (1) no absence of more than a week due to injury or other conditions during the five months of observation and (2) physical assessments having been done simultaneously with those of the other players (at the beginning of the season). The exclusion criteria were (1) not participating in one week or more of training sessions, and (2) not participating in the physical fitness assessments. At the beginning of the season, players were assessed for anthropometry (height, body mass, skinfolds), countermovement jump, triple hop bilateral and unilateral jump, and aerobic capacity using the Yo-Yo Intermittent Recovery Test, level 2 (YYIRT). The group that played more time had significantly greater YYIRT results (+28.2%; p = 0.009; Cohen’s d = 0.664). No other significant differences were found between those who played more and fewer minutes. Moderate and significant linear positive correlations were found between YYIRT and play time in the under-19 group (r = 0.423; p = 0.031) and overall (r = 0.401; p < 0.001). In the case of the under-17 group, moderate and significant linear positive correlations were found between TSA and play time (r = 0.473; p = 0.041). This suggests that aerobic and anaerobic capacity is related to play time while jumping performance and fat mass seem not to play an essential role in play time.

Relationship between Anthropometric Measures and Anxiety Perception in Soccer Players

In the sports context, it has been corroborated that the physical demands of presenting an “ideal” body configuration have been associated with different psychological variables, such as self-esteem, anxiety and personality dimensions, such as perfectionism. Specifically, there is evidence that anthropometric measures may be closely related to psychological indicators. A total of 33 male soccer players (18.12 ± 1.24 years) participated in the investigation. Anthropometric assessments were carried out following the ISAK standards for the restricted profile. All of them completed the Competitive Trait Anxiety Inventory (CTAI-2D) in its Spanish version. The percent fat was calculated using Withers (density) and Siri equations. The ∑7 skinfolds were used to calculate this. After statistical analysis, significant mean differences were observed in the somatic anxiety dimension (valence) and a medium–large effect size. Regarding correlations, the significantly negative relationship between self-confidence (intentionality) and somatic anxiety (valence) was noteworthy. The relationship between psychological variables and anthropometric measurements was corroborated, showing the need for interdisciplinary work between psychologists and nutritionists who do not ignore the physical health and psychological well-being of the soccer player.

Relationship between Type and Intensity of Sports Activities and the Prevalence of Overweight in Serbian School Children

This study aimed to explore the relationship between different forms and intensities of sports activities and the prevalence of overweight in primary school children. Using International Obesity Task Force BMI criteria, we have identified body weight status in a group of 2893 children aged 9–15 years participating in 27 different sports and within a group of 4987 non-active children of the same age. We have compared the prevalence of overweight and obesity between these groups, as well as between genders and different forms and intensities of sports, within the group of active children. We have found lower prevalence of overweight (Χ2 = 41.689, DF = 1, p < 0.001), as well as prevalence of obesity (Χ2 = 175.184, DF = 1, p < 0.001) in physically active children compared with their non-active counterparts, as expected. Overweight (including obesity) had the highest prevalence in mixed sports of the Classification of Sports of the European Association of Preventive Cardiology, in boys (p = 0.003), as well as in girls (p = 0.043). A lower prevalence of overweight was noted in boys (p = 0.001), as well as in girls (p = 0.025) with more than 7 years of training. Regarding the number of hours of training per week, a lower prevalence of overweight was noted only in girls with 4 and more hours of training per week (p = 0.025). Concerning intensity, we have found a significant drop in the prevalence of overweight in children with sports activities whose intensity is more than 60 MET-hours per week. We conclude that a significant relationship between sports and the prevalence of overweight is found in children with more than 60 MET-hours of sports activities per week, as well as among children involved in mixed sports, and after more than 7 years spent in regular sports training.

Assessment of Body Composition and Physical Performance of Young Soccer Players: Differences According to the Competitive Level

Soccer is a multifactorial sport, in which players are expected to possess well developed physical, psychological, technical, and tactical skills. Thus, the anthropometric and fitness measures play a determinant role and could vary according to the competitive level. Therefore, the present study aimed to verify differences in body composition and physical performance between two soccer team. 162 young soccer players (from the Under 12 to Under 15 age categories; age: 13.01 ± 1.15 years) of different competitive levels (elite—n = 98 and non-elite—n = 64) were recruited. Anthropometric characteristics (height, weight, lengths, widths, circumferences, and skinfold thicknesses (SK)), bioelectrical impedance, physical performance test as countermovement jump (CMJ), 15 m straight-line sprints, Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo), and 20 + 20 m repeated-sprint ability (RSA)) were carried out. In addition, Body mass index (BMI), body composition parameters (percentage of fat mass (%F), Fat mass (FM, kg), and Fat-free mass (FFM, kg)) and the areas of the upper arm, calf and thigh were calculated, and the Bioelectric Impedance Vector Analysis (BIVA) procedures were applied. In addition, a linear discriminant analysis was assessed to determine which factors better discriminate between an elite and non-elite football team. Many differences were observed in body composition between and within each football team’s category, especially in triceps SK (p < 0.05), %F (p < 0.05), and all performance tests (p < 0.01). The canonical correlation was 0.717 (F(7,128) = 19.37, p < 0.0001), and the coefficients that better discriminated between two teams were 15 m sprint (−2.39), RSA (1−26), suprailiac SK (−0.5) and CMJ (−0.45). Elite soccer team players present a better body composition and greater physical efficiency. In addition, BIVA outcome could be a relevant selection criterion to scout among younger soccer players.