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Titheradge P, Robergs R. Evaluating Airflow Sensor Methods: Precision in Indirect Calorimetry. Scand J Med Sci Sports 2024; 34:e14674. [PMID: 38895762 DOI: 10.1111/sms.14674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 05/21/2024] [Accepted: 05/22/2024] [Indexed: 06/21/2024]
Abstract
This study assesses the impact of three volumetric gas flow measurement methods-turbine (fT); pneumotachograph (fP), and Venturi (fV)-on predictive accuracy and precision of expired gas analysis indirect calorimetry (EGAIC) across varying exercise intensities. Six males (Age: 38 ± 8 year; Height: 178.8 ± 4.2 cm;V ̇ O 2 peak $$ \dot{V}{\mathrm{O}}_2\mathrm{peak} $$ : 42 ± 2.8 mL O2 kg-1 min-1) and 14 females (Age = 44.6 ± 9.6 year; Height = 164.6 ± 6.9 cm;V ̇ O 2 peak $$ \dot{V}{\mathrm{O}}_2\mathrm{peak} $$ = 45 ± 8.6 mL O2 kg-1 min-1) were recruited. Participants completed physical exertion on a stationary cycle ergometer for simultaneous pulmonary minute ventilation (V ̇ $$ \dot{V} $$ ) measurements and EGAIC computations. Exercise protocols and subsequent conditions involved a 5-min cycling warm-up at 25 W min-1, incremental exercise to exhaustion (V ̇ O 2 $$ \dot{V}{\mathrm{O}}_2 $$ ramp test), then a steady-state exercise bout induced by a constant Watt load equivalent to 80% ventilatory threshold (80% VT). A linear mixed model revealed that exercise intensity significantly affectedV ̇ O 2 $$ \dot{V}{\mathrm{O}}_2 $$ measurements (p < 0.0001), whereas airflow sensor method (p = 0.97) and its interaction with exercise intensity (p = 0.91) did not. Group analysis of precision yielded aV ̇ O 2 $$ \dot{V}{\mathrm{O}}_2 $$ CV % = 21%; SEM = 5 mL O2 kg-1 min-1. Intra- and interindividual analysis of precision via Bland-Altman revealed a 95% confidence interval (CI) precision benchmark of 3-5 mL kg-1 min-1. Agreement among methods decreased at power outputs elicitingV ̇ $$ \dot{V} $$ up to 150 L min-1, indicating a decrease in precision and highlighting potential challenges in interpreting biological variability, training response heterogeneity, and test-retest comparisons. These findings suggest careful consideration of airflow sensor method variance across metabolic cart configurations.
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Affiliation(s)
- Praneel Titheradge
- School of Allied Health, Exercise & Sports Sciences, Charles Sturt University, Port Macquarie, New South Wales, Australia
| | - Robert Robergs
- School of Exercise & Nutrition Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Queensland, Australia
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Nobari H, Eken Ö, Singh U, Gorouhi A, Bordón JCP, Prieto-González P, Kurtoğlu A, Calvo TG. Which training load indicators are greater correlated with maturation and wellness variables in elite U14 soccer players? BMC Pediatr 2024; 24:289. [PMID: 38689258 PMCID: PMC11059657 DOI: 10.1186/s12887-024-04744-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Accepted: 04/08/2024] [Indexed: 05/02/2024] Open
Abstract
BACKGROUND Monitoring of training load is done to improve physical performance and minimize the incidence of injuries. The study examined the correlation between accumulated training load parameters based on periods with maturity (i.e., maturity offset and peak height velocity -PHV- and wellness variables -e.g., stress and sleep quality-). The second aim was to analyze the multi-linear regression between the above indicators. METHODS Twenty elite young U14 soccer players (M = 13.26 ± 0.52 years, 95% CI [13.02, 13.51]) were evaluated over 26 weeks (early, mid, and end-season) to obtain stress, sleep quality, and measures of workload in the season (accumulated acute workload [AW], accumulated chronic workload [CW], accumulated acute: chronic workload ratio [ACWLR], accumulated training monotony [TM], accumulated training strain [TS]). RESULTS The analysis revealed a moderate, statistically significant negative correlation between sleep quality and training monotony (r = -0.461, p < 0.05). No significant correlations were observed between other variables (p > 0.05). In the multi-linear regression analysis, maturity, PHV, sleep, and stress collectively accounted for variances of 17% in AW, 17.1% in CW, 11% in ACWLR, 21.3% in TM, and 22.6% in TS. However, individual regression coefficients for these predictors were not statistically significant (p > 0.05), indicating limited predictive power. CONCLUSION The study highlights the impact of sleep quality on training monotony, underscoring the importance of managing training load to mitigate the risks of overtraining. The non-significant regression coefficients suggest the complexity of predicting training outcomes based on the assessed variables. These insights emphasize the need for a holistic approach in training load management and athlete wellness monitoring.
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Affiliation(s)
- Hadi Nobari
- Faculty of Sport Sciences, University of Extremadura, Cáceres, 10003, Spain.
- Department of Exercise Physiology, Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, Ardabil, 56199-11367, Iran.
| | - Özgür Eken
- Physical Education and Sports Teaching, Faculty of Sport Science, Inonu University, Battalgazi, Malatya, Türkiye
| | - Utkarsh Singh
- Sport and Exercise Science, College of Healthcare Sciences, James Cook University, Townsville, Australia
- Sports Dynamix Private Limited, Chennai, India
| | - Armin Gorouhi
- University of A Coruña, A Coruña, 15001, Spain
- Physical Activity and Health Promotion, Department of Biomedicine, University of Tor Vergata, Rome, Italy
| | | | - Pablo Prieto-González
- Health and Physical Education Department, Prince Sultan University, Riyadh, 11586, Saudi Arabia
| | - Ahmet Kurtoğlu
- Department of Coaching Education, Faculty of Sport Science, Bandirma Onyedi Eylul University, Balikesir, 10200, Türkiye
| | - Tomás García Calvo
- Faculty of Sport Sciences, University of Extremadura, Cáceres, 10003, Spain.
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Nobari H, Eken Ö, Kamiş O, Oliveira R, González PP, Aquino R. Relationships between training load, peak height velocity, muscle soreness and fatigue status in elite-level young soccer players: a competition season study. BMC Pediatr 2023; 23:55. [PMID: 36732715 PMCID: PMC9896692 DOI: 10.1186/s12887-023-03869-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 01/27/2023] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND This study aimed to compare training load parameters, delayed onset muscle soreness (DOMS), and fatigue status between season periods (1st and 2nd halves) in U14 soccer players and to analyze the relationships between training load parameters based on season periods (1st and 2nd halves) with peak height velocity (PHV), DOMS, and fatigue status in under-14 (U14) young elite soccer players. Additionally, it was intended to analyze if fatigue, DOMS and PHV could explain training load parameters across the season. METHODS Twenty U14 players that competed in the national league participated in this study. The players were monitored during the whole season (26 weeks), and evaluations were carried out at the end of the in-season. Anthropometric and body composition parameters and the maturity offset of each player were utilized to compute each player's age at PHV. Players reported their levels of DOMS and fatigue status using Hooper index questionnaires. The internal load was monitored using the rating of perceived exertion (RPE). Acute weekly internal load (AW), chronic weekly internal load (CW), acute: chronic workload ratio (ACWR), training monotony (TM), and training strain (TS) were also obtained. RESULTS The main results showed that TM was higher in the 2nd half, while CW, AW and DOMS were higher in the 1st half of the season. Moreover, the main correlations showed a positive correlation between PHV and TS (2nd half of the season) and between fatigue and TM (1st half of the season). CONCLUSION In conclusion, variations in well-being status and PHV cannot explain the variations in internal training loads in elite U14 soccer players. In addition, internal training load indices during the first half of the competitive season can promote a fundamental base for progression loads during the second period of the competitive season.
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Affiliation(s)
- Hadi Nobari
- Department of Exercise Physiology, Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, Ardabil, 56199-11367, Iran. .,Department of Motor Performance, Faculty of Physical Education and Mountain Sports, Transilvania University of Braşov, 500068, Braşov, Romania. .,Faculty of Sports Sciences, University of Extremadura, 10003, Cáceres, Spain.
| | - Özgür Eken
- grid.411650.70000 0001 0024 1937Department of Physical Education and Sport Teaching, Inonu University, Malatya, Turkey
| | - Okan Kamiş
- grid.411297.80000 0004 0384 345XFaculty of Sports Sciences, Aksaray University, 68100 Aksaray, Türkiye
| | - Rafael Oliveira
- Sports Science School of Rio Maior—Polytechnic Institute of Santarém, 2040-413 Rio Maior, Portugal ,Research Center in Sport Sciences, Health Sciences and Human Development, 5001-801 Vila Real, Portugal ,grid.512803.dLife Quality Research Centre, 2040-413 Rio Maior, Portugal
| | - Pablo Prieto González
- grid.443351.40000 0004 0367 6372Health and Physical Education Department, Prince Sultan University, Riyadh, 11586 Saudi Arabia
| | - Rodrigo Aquino
- grid.412371.20000 0001 2167 4168Lab Sport, Department of Sports, Centre of Physical Education and Sports, Federal University of Espírito Santo, Vitória, 29075810 Brazil
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Does maturity estimation, 2D:4D and training load measures explain physical fitness changes of youth football players? BMC Pediatr 2022; 22:726. [PMID: 36539728 PMCID: PMC9764734 DOI: 10.1186/s12887-022-03801-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Accepted: 12/14/2022] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVES The purpose of the present study was two-fold: (1) To analyse physical fitness changes of youth football players after a full-season; and (2) to examine whether physical fitness changes are explainable by estimated maturity status, 2digit:4digit ratio (2D:4D) from each hand and training load (TL) measures. METHODS Twenty-seven youth elite Under-15 football players were daily monitored for training load measures during 38 weeks. At the beginning and at the end of the season, all players were assessed for physical fitness. Also, the maturity status estimation and the length of the second and fourth digits of both hands were collected at the beginning of the season. RESULTS Significant differences were found for all physical fitness measures after the season. The second and fourth digits of left and right hands had negative moderate correlations with change of direction (COD) changes (r=-.39 to - 0.45 | p = .05 to 0.02). Also, the maturity offset measure had negative moderate correlations with COD changes (r=-.40 | p = .04). From the reported significant correlations, the maturity offset, Left 4D, Right 2D and Right 4D significantly predicted the Mod.505 COD test changes (β = 0.41, p = .04; β = -0.41, p = .04; β = -0.45, p = .02; and β = -0.44, p = .03, respectively). CONCLUSION The maturity offset and the 2D:4D measures have the potential to predict COD performance changes over-time in youth football players. Given the lack of associations between the maturity estimation, 2D:4D and training load measures, with the overall physical fitness measures, coaches should rely only at COD changes.
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Cartón-Llorente A, Roche-Seruendo LE, Mainer-Pardos E, Nobari H, Rubio-Peirotén A, Jaén-Carrillo D, García-Pinillos F. Acute effects of a 60-min time trial on power-related parameters in trained endurance runners. BMC Sports Sci Med Rehabil 2022; 14:142. [PMID: 35871673 PMCID: PMC9310469 DOI: 10.1186/s13102-022-00538-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 07/20/2022] [Indexed: 11/10/2022] Open
Abstract
Background The advent of power meters for running has raised the interest of athletes and coaches in new ways of assessing changes in running performance. The aim of this study is to determine the changes in power-related variables during and after a strenuous endurance running time trial.
Methods Twenty-one healthy male endurance runners, with a personal record of 37.2 ± 1.2 min in a 10-km race, completed a 1-h run on a motorized treadmill trying to cover as much distance as they could. Before and after the time trial the athletes were asked to perform a 3-min run at 12 km h−1. Normalized mean power output, step frequency, form power and running effectiveness were calculated using the Stryd™ power meter. Heart rate (HR) and rating of perceived exertion (RPE) were monitored, and data averaged every 5 min. Results Despite high levels of exhaustion were reached during the time trial (HRpeak = 176.5 ± 9.8 bpm; RPE = 19.2 ± 0.8), the repeated measures ANOVA resulted in no significant differences (p ≥ 0.05), between each pair of periods for any of the power-related variables. The pairwise comparison (T test) between the non-fatigued and fatigued constant 3-min runs showed an increase in step frequency (p = 0.012) and a decrease in form power (p < 0.001) under fatigue conditions, with no meaningful changes in normalized mean power output and running effectiveness. Conclusions Trained athletes are able to maintain power output and running effectiveness during a high demanding extended run. However, they preferred to reduce the intensity of vertical impacts under fatigue conditions by increasing their step frequency.
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Effects of a small-sided games training program in youth male soccer players: variations of the locomotor profile while interacting with baseline level and with the accumulated load. BMC Sports Sci Med Rehabil 2022; 14:198. [DOI: 10.1186/s13102-022-00595-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 11/18/2022] [Indexed: 11/25/2022]
Abstract
Abstract
Purpose
This study aimed to (1) analyze the impact of a small-sided game training program in the locomotor profile of youth male soccer players (while interacting with the baseline level – higher and lower level); and (2) test the relationships between variation in locomotor profile and the accumulated demands in 3v3, 5v5 and match over the period of observation.
Methods
The cohort lasted 3-weeks. Twenty under-17 male amateur soccer players (16.8 ± 0.41 years; experience: 6.35 ± 0.67 years) were assessed twice for their final velocity at 30−15 intermittent fitness test (VIFT), peak speed at 30-m sprint test (PSS) and anaerobic speed reserve (ASR). The PSS was estimated using a Global Positioning System, while the VIFT was estimated using the maximum level attained by the players during the test. Based on the baseline levels, the scores were standardized using the Z-score. The total score of athleticism (TSA) was calculated per player to organize the players into two groups: lower TSA and higher TSA. Over the three weeks of observation, the small-sided games of 3v3 and 5v5 and match demands were monitored using polar team pro. The heart rate responses (mean and peak), distance covered (overall and split by speed thresholds), and peak speed in these games were obtained and summed over the weeks. The repeated measures ANCOVA tested the variations (time) of the locomotor profile of players while considering the baseline as covariable and the group as a factor. The Pearson-product correlation test analyzed the relationships between variations in locomotor profile (Δ, post-baseline) and the accumulated demands in 3v3, 5v5, and match.
Results
Between-groups analysis (lower TSA vs. higher TSA) revealed no significant differences on VIFT (p = 0.915), PSS (p = 0.269), ASR (p = 0.258) and TSA score (p = 0.138). Within-group (baseline vs. post-observation) analysis revealed significant difference on VIFT (p < 0.001), PSS (p = 0.008), while no significant differences were found on ASR (p = 0.949) and TSA score (p = 0.619). Significant correlations were found between ΔPSS and match total distance (r = 0.444; p = 0.050), match Z2 (r = 0.481; p = 0.032) and match Z3 (r = 0.454; p = 0.044). Significant correlations were found between ΔTSA and match total distance (r = 0.457; p = 0.043), match Z1 (r = 0.451; p = 0.046), match Z2 (r = 0.500; p = 0.025) and match Z3 (r = 0.468; p = 0.037).
Conclusion
Significant improvements were observed after the period of observation. However, the fitness baseline level and the accumulated training load in the small-sided games seem to have no significant impact on the observed improvements.
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Variations in Accumulated-Training Load Parameters and Locomotor Demand with Consideration of Puberty in Elite Young Soccer Players. BIOLOGY 2022; 11:biology11111594. [PMID: 36358295 PMCID: PMC9687643 DOI: 10.3390/biology11111594] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 10/19/2022] [Accepted: 10/26/2022] [Indexed: 11/07/2022]
Abstract
The study’s purposes were to examine the associations of training load parameters with locomotor demand and puberty status in elite young soccer players and to predict the percentage of changes in their performance ability with adjustments to the training load parameters, using multivariate regression analysis, while considering PHV and maturity offset. Seventeen male players (15−16 years old) participated in this study. Anthropometrics, body composition, maximal oxygen consumption (VO2max), and puberty status (for calculating PHV) and maturity offset were assessed. The results demonstrated substantial differences between the PHV, VO2max, and load parameters (acute and chronic workload (CWL)) over a soccer season. A substantial relationship existed between the workload parameters (VO2max, CWL, and training monotony (TM)) and maturity offset. All of the variables, except for training strain, demonstrated significant variances in relation to the differences between the first and second halves (p < 0.05). Aerobic performance can be estimated using the CWL, TM, and maturity offset values (R2 = 0.46). On the contrary, aerobic power performance can be explained using the acute:chronic workload, TM, and PHV values (R2 = 0.40). In conclusion, the biological maturity state of young soccer players has a substantial impact on their functional potential. Variations in accumulated load contribute significantly to aerobic resistance, whereas weight and height contribute significantly to sprint and vertical-jump performance, respectively.
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Turcu I, Oancea B, Chicomban M, Simion G, Simon S, Negriu Tiuca CI, Ordean MN, Petrovici AG, Nicolescu Șeușan NA, Hăisan PL, Hășmășan IT, Hulpuș AI, Stoian I, Ciocan CV, Curițianu IM. Effect of 8-Week β-Alanine Supplementation on CRP, IL-6, Body Composition, and Bio-Motor Abilities in Elite Male Basketball Players. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph192013700. [PMID: 36294288 PMCID: PMC9603793 DOI: 10.3390/ijerph192013700] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 10/18/2022] [Accepted: 10/19/2022] [Indexed: 06/01/2023]
Abstract
The purpose of this study was to evaluate the effect of 8-week β-alanine supplementation on C-Reactive Protein (CRP), interleukin-6 (IL-6), body composition, and bio-motor abilities in elite male basketball players. Twenty male basketball players (age: 23 + 0.6 years; body mass: 78.3 + 4.8 kg; height:185.3 + 5.4 cm, %BF, 15.2 ± 4.8) volunteered to participate in this study. They were divided into a β-alanine group (BG, N = 10) and a placebo group (PG, N = 10). All players were preparing for university competitions and had played for over five years. Players used 6.4 g/d of β-alanine in BG and maltodextrin in PG. The participants were involved in regular basketball training three months before the study. CRP, IL-6, body composition parameters, and bio-motor abilities were measured before starting the exercises and after completing the eight-week training period. The research findings showed a significant decrease in CRP and IL-6 and an increase in anaerobic peak power between the pre-test and post-test, as well as between BG and PG groups (p < 0.05). Although the other measured factors were a relative improvement compared to the pre-test and also compared to PG, these changes were not statistically significant (p < 0.05). Eight weeks of β-alanine supplementation ameliorated increases in IL-6 and CRP associated with in-season physical stressors in collegiate basketball players. These changes in pro-inflammatory cytokines suggest that β-alanine supplementation may be a useful nutritional strategy for immune regulation and can also improve anaerobic performance compared to PG.
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Affiliation(s)
- Ioan Turcu
- Department of Motor Performance, Faculty of Physical Education and Mountain Sports, Transilvania University of Brasov, 500036 Brasov, Romania
| | - Bogdan Oancea
- Department of Motor Performance, Faculty of Physical Education and Mountain Sports, Transilvania University of Brasov, 500036 Brasov, Romania
| | - Mihaela Chicomban
- Department of Motor Performance, Faculty of Physical Education and Mountain Sports, Transilvania University of Brasov, 500036 Brasov, Romania
| | - Gabriel Simion
- Department of Motor Performance, Faculty of Physical Education and Mountain Sports, Transilvania University of Brasov, 500036 Brasov, Romania
| | - Sorin Simon
- Department of Physical Education and Sport, 1 Decembrie 1918 University of Alba Iulia, 510009 Alba Iulia, Romania
| | - Codruța Ioana Negriu Tiuca
- Department of Physical Education and Sport, 1 Decembrie 1918 University of Alba Iulia, 510009 Alba Iulia, Romania
| | - Mircea Nicolae Ordean
- Department of Physical Education and Sport, 1 Decembrie 1918 University of Alba Iulia, 510009 Alba Iulia, Romania
| | - Alexandru Gabriel Petrovici
- Department of Physical Education and Sport, 1 Decembrie 1918 University of Alba Iulia, 510009 Alba Iulia, Romania
| | | | - Petronela Lăcrămioara Hăisan
- Department of Physical Education and Sport, 1 Decembrie 1918 University of Alba Iulia, 510009 Alba Iulia, Romania
| | - Ioan Teodor Hășmășan
- Department of Environmental Sciences Physics Physical Education and Sport, Faculty of Science, Lucian Blaga University of Sibiu, 550024 Sibiu, Romania
| | - Alexandru Ioan Hulpuș
- Department of Environmental Sciences Physics Physical Education and Sport, Faculty of Science, Lucian Blaga University of Sibiu, 550024 Sibiu, Romania
| | - Iulian Stoian
- Department of Environmental Sciences Physics Physical Education and Sport, Faculty of Science, Lucian Blaga University of Sibiu, 550024 Sibiu, Romania
| | - Cătălin Vasile Ciocan
- Department of Physical Education and Sports Performance, Faculty of Physical Education, Sport and Health Sciences, Vasile Alecsandri of Bacau, 600115 Bacau, Romania
| | - Ioana Maria Curițianu
- Department of Physical Education and Special Motricity, Faculty of Physical Education and Mountain Sports, Transilvania University of Brasov, 500036 Brasov, Romania
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Effects of small-sided games and running-based high-intensity interval training on body composition and physical fitness in under-19 female soccer players. BMC Sports Sci Med Rehabil 2022; 14:119. [PMID: 35765044 PMCID: PMC9238068 DOI: 10.1186/s13102-022-00516-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 06/24/2022] [Indexed: 11/10/2022]
Abstract
Background The aim of this study was to compare the effects of small-sided games (SSGs) and running-based high-intensity interval training (HIIT) on the body composition and physical fitness of youth female soccer players.
Methods This study followed a randomized parallel study design. Twenty-four female soccer players (age: 18.63 ± 2.36 years) were randomly allocated to two training groups (SSG, n = 12; and HIIT, n = 12). The training intervention had a duration of eight weeks, consisting of three training sessions per week. Players were assessed twice (pre- and post-intervention) for anthropometrics, vertical (countermovement jumps, CMJ; and drop jumps, DJ) and horizontal jumping (single, triple and crossover hop), sprinting (10- and 30-m), change-of-direction (COD), COD deficit and final velocity at 30–15 Intermittent Fitness Test (VIFT). A covariance analysis (ANCOVA) was used to determine differences between the groups in the effect on post-intervention by controlling for covariates (pre-intervention). The within-group analysis (time) was performed using a paired t-test, while the between-group analysis per assessment moment was performed using an independent t-test. Results The between-group analysis with ANCOVA revealed that there are no significant differences between the SSG and HIIT groups in the post-intervention for any outcome (p > 0.05). The within-group analysis revealed significant improvements in both the SSG and HIIT groups in CMJ (p < 0.05), single, triple and crossover hops (p < 0.05), RSI DJ 30-cm and RSI DJ 40-cm (p < 0.05), VIFT (p < 0.05) and COD (p < 0.05). Conclusions SSG and HIIT are both effective for improving vertical and horizontal jumping ability, change-of-direction, and aerobic capacity status measured at a progressive and intermittent multistage test in youth soccer players.
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Bezuglov E, Emanov A, Waśkiewicz Z, Semeniuk N, Butovsky M, Shoshorina M, Baranova D, Volodina K, Morgans R. Successful Young Athletes Have Low Probability of Being Ranked Among the Best Senior Athletes, but This Is Higher When Compared to Their Less Successful Peers. Front Psychol 2022; 13:869637. [PMID: 35719603 PMCID: PMC9202474 DOI: 10.3389/fpsyg.2022.869637] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 04/11/2022] [Indexed: 01/02/2023] Open
Abstract
Background Contemporary research has shown that only a small proportion of high achieving young athletes continue to become successful senior athletes. However, there is a lack of empirical literature tracking the success of senior male and female athletes who were considered high achieving as a youth. Hypothesis Athletes of both sexes who are successful in youth categories (U18 and U20) are more likely to be successful senior athletes. Conclusion Data from 67,600 athletes were collated from the tilastopaja.org platform. The inclusion criteria for both genders were determined by top-100 ranking in the U18 and U20 age groups and progression to the top-100 as a senior athlete. Only 23.5% of successful track and field athletes (ranked in top-100) at U18 became a successful senior athlete, while 35.4% were from the U20 group. Girls ranked in the top-100 U18 and U20 categories are significantly more likely to be ranked in the top-100 as a senior when compared to boys. Although, being ranked in the top-50 at U18 and U20 significantly increases the probability of becoming a successful senior athlete when compared with less successful athletes at these age groups (p < 0.001). Notably, the majority (68.5%) of the most successful senior athletes were not ranked in the top-100 when in the U18 or U20 age groups. Only a small group of track and field athletes that are successful at U18 and U20 become successful at senior level. The most successful track and field youth athletes are significantly more likely to succeed as a senior athlete than their less successful peers, while girls are more likely to be successful than boys.
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Affiliation(s)
- Eduard Bezuglov
- Department of Sports Medicine and Medical Rehabilitation, Sechenov First Moscow State Medical University of the Ministry of Health of the Russia Federation, Moscow, Russia.,High Performance Sport Laboratory, Moscow Witte University, Moscow, Russia.,Sirius University of Science and Technology, Sochi, Russia.,Professional Football Club CSKA, Moscow, Russia
| | - Anton Emanov
- "Smart Recovery" Sports Medicine Clinic LLC, Moscow, Russia
| | - Zbigniew Waśkiewicz
- Department of Sports Medicine and Medical Rehabilitation, Sechenov First Moscow State Medical University of the Ministry of Health of the Russia Federation, Moscow, Russia.,Institute of Sport Science, Jerzy Kukuczka Academy of Physical Education, Katowice, Poland
| | | | | | - Maria Shoshorina
- Department of Sports Medicine and Medical Rehabilitation, Sechenov First Moscow State Medical University of the Ministry of Health of the Russia Federation, Moscow, Russia
| | - Daria Baranova
- Department of Sports Medicine and Medical Rehabilitation, Sechenov First Moscow State Medical University of the Ministry of Health of the Russia Federation, Moscow, Russia
| | - Kristina Volodina
- Department of Sports Medicine and Medical Rehabilitation, Sechenov First Moscow State Medical University of the Ministry of Health of the Russia Federation, Moscow, Russia
| | - Ryland Morgans
- Department of Sports Medicine and Medical Rehabilitation, Sechenov First Moscow State Medical University of the Ministry of Health of the Russia Federation, Moscow, Russia
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Relationship between Variations in the Accumulated Workload and the Change of Direction Ability in Elite Young Soccer Players. SUSTAINABILITY 2022. [DOI: 10.3390/su14095535] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Background: The main aim of this study was to evaluate the relationships between training workload (WL) parameters with variations in the change of direction (COD) in under-16 soccer players. Methods: Twenty-seven under-16 elite soccer players were daily monitored for their WL across 15 weeks during the competitive soccer season. Additionally, players were assessed two times for anthropometric measures (weight, height, sitting height and leg length), COD performance (modified 505 test) and maturity offset measured using the peak height velocity (PHV). Results: A correlational analysis was performed to determine the relationship between the variation in COD performance and accumulated WL parameters. Moreover, a regression analysis was executed to explain the variations in the percentage of COD performance considering the accumulated WL parameters and PHV of the season (r = 0.93; p ≤ 0.01) and training monotony during the early-season (r = 0.53; p ≤ 0.05). There were associations between the acute workload during the start of the season and the COD during the end of the season (r = 0.47; p ≤ 0.05). The multiple linear regression analysis showed that 55% of the variation in COD performance between the early and end of season could be explained by the acute or chronic WL, training monotony or strain and the PHV. Conclusions: This information might be useful for practitioners and coaches aiming to improve the COD performance in youth soccer players during an entire competitive season.
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Eskandarifard E, Nobari H, Clemente FM, Silva R, Silva AF, Figueiredo AJ. Associations between match participation, maturation, physical fitness, and hormonal levels in elite male soccer player U15: a prospective study with observational cohort. BMC Pediatr 2022; 22:196. [PMID: 35410178 PMCID: PMC8996429 DOI: 10.1186/s12887-022-03257-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 03/31/2022] [Indexed: 11/19/2022] Open
Abstract
Objectives The aims of this study were to analyze the relationships between minutes of play (MP) and maturity status, fitness, and hormonal levels and to explain how those measures influence the time of play. Methods Twenty-six youth soccer players U15 participated in this study over a full-season period. Anthropometric measures, maturity status, growth hormone (GH), insulin-like growth factor and physical levels such as maximal oxygen uptake (VO2max), fatigue index, countermovement jump (CMJ) performance were collected. At the end-season, players were assessed in 6 different tests over four days. Results VO2max largely correlated with GH (r = 0.57) and CMJ (r = 0.51). Also, GH largely correlated with CMJ (r = 0.55). MP had moderate correlations with VO2max (r = 0.44) and CMJ (r = 0.42). Multiple linear regression with maturation, physical fitness and hormonal levels explained R2 of 0.62 of the MP (F (8, 17) = 3.47, p = 0.015). Although each independent variable alone was not able to determine the playing time, when using the interactions, the model significantly explained the MP. Conclusions The combination of maturity status, physical fitness, and hormonal levels seem to play a determinant role in explaining the match participation in youth soccer players.
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Affiliation(s)
- Ebrahim Eskandarifard
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan, 81746-7344, Iran.,Faculty of Sport Sciences and Physical Education, University of Coimbra, Coimbra, Portugal
| | - Hadi Nobari
- Department of Exercise Physiology, Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, Ardabil, 56199-11367, Iran. .,Sports Scientist, Sepahan Football Club, Isfahan, 81887-78473, Iran. .,Department of Physiology, Faculty of Sport Sciences, University of Extremadura, Cáceres, 10003, Spain.
| | - Filipe Manuel Clemente
- Escola Superior Desporto e Lazer, Instituto Politécnico de Viana do Castelo, Rua Escola Industrial e Comercial de Nun'Álvares, Viana do Castelo, 4900-347, Portugal.,Instituto de Telecomunicações, Delegação da Covilhã, Lisboa, 1049-001, Portugal
| | - Rui Silva
- Escola Superior Desporto e Lazer, Instituto Politécnico de Viana do Castelo, Rua Escola Industrial e Comercial de Nun'Álvares, Viana do Castelo, 4900-347, Portugal.,Research Center in Sports Performance, Recreation, Innovation and Technology (SPRINT), Melgaço, 4960-320, Portugal
| | - Ana Filipa Silva
- Escola Superior Desporto e Lazer, Instituto Politécnico de Viana do Castelo, Rua Escola Industrial e Comercial de Nun'Álvares, Viana do Castelo, 4900-347, Portugal.,Research Center in Sports Performance, Recreation, Innovation and Technology (SPRINT), Melgaço, 4960-320, Portugal.,The Research Centre in Sports Sciences, Health Sciences and Human Development (CIDESD), Vila Real, 5001-801, Portugal
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Teixeira JE, Alves AR, Ferraz R, Forte P, Leal M, Ribeiro J, Silva AJ, Barbosa TM, Monteiro AM. Effects of Chronological Age, Relative Age, and Maturation Status on Accumulated Training Load and Perceived Exertion in Young Sub-Elite Football Players. Front Physiol 2022; 13:832202. [PMID: 35432006 PMCID: PMC9010324 DOI: 10.3389/fphys.2022.832202] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 03/07/2022] [Indexed: 01/12/2023] Open
Abstract
The aims of this study were 1) to analyze the influence of chronological age, relative age, and biological maturation on accumulated training load and perceived exertion in young sub-elite football players and 2) to understand the interaction effects amongst age grouping, maturation status, and birth quartiles on accumulated training load and perceived exertion in this target population. A 6-week period (18 training sessions and 324 observation cases) concerning 60 young male sub-elite football players grouped into relative age (Q1 to Q4), age group (U15, U17, and U19), and maturation status (Pre-peak height velocity (PHV), Mid-PHV, and Post-PHV) was established. External training load data were collected using 18 Hz global positioning system technology (GPS), heart-rate measures by a 1 Hz short-range telemetry system, and perceived exertion with total quality recovery (TQR) and rating of perceived exertion (RPE). U17 players and U15 players were 2.35 (95% CI: 1.25–4.51) and 1.60 (95% CI: 0.19–4.33) times more likely to pertain to Q1 and Q3, respectively. A negative magnitude for odds ratio was found in all four quartile comparisons within maturation status (95% CI: 6.72–0.64), except for Mid-PHV on Q2 (95% CI: 0.19–4.33). Between- and within-subject analysis reported significant differences in all variables on age group comparison measures (F = 0.439 to 26.636, p = 0.000 to 0.019, η2 = 0.003–0.037), except for dynamic stress load (DSL). Between-subject analysis on maturity status comparison demonstrated significant differences for all training load measures (F = 6.593 to 14.424, p = 0.000 to 0.037, η2 = 0.020–0.092). Interaction effects were found for age group x maturity band x relative age (Λ Pillai’s = 0.391, Λ Wilk’s = 0.609, F = 11.385, p = 0.000, η2 = 0.391) and maturity band x relative age (Λ Pillai’s = 0.252, Λ Wilk’s = 0.769, F = 0.955, p = 0.004, η2 = 0.112). Current research has confirmed the effects of chronological age, relative age, and biological maturation on accumulated training load. Perceived exertion does not seem to show any differences concerning age group or maturity status. Evidence should be helpful for professionals to optimize the training process and young football players’ performance.
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Affiliation(s)
- José Eduardo Teixeira
- Research Centre in Sports Sciences, Health and Human Development, Vila Real, Portugal
- Department of Sports, Exercise and Health Sciences, University of Trás-os-Montes e Alto Douro, Vila Real, Portugal
- Department of Sport Sciences, Instituto Politécnico de Bragança, Bragança, Portugal
- *Correspondence: José Eduardo Teixeira,
| | - Ana Ruivo Alves
- Research Centre in Sports Sciences, Health and Human Development, Vila Real, Portugal
- Department of Sport Sciences, University of Beira Interior, Covilhã, Portugal
| | - Ricardo Ferraz
- Research Centre in Sports Sciences, Health and Human Development, Vila Real, Portugal
- Department of Sport Sciences, University of Beira Interior, Covilhã, Portugal
| | - Pedro Forte
- Research Centre in Sports Sciences, Health and Human Development, Vila Real, Portugal
- Department of Sport Sciences, Instituto Politécnico de Bragança, Bragança, Portugal
- Department of Sports, Douro Higher Institute of Educational Sciences, Penafiel, Portugal
| | - Miguel Leal
- Department of Sports, Douro Higher Institute of Educational Sciences, Penafiel, Portugal
| | - Joana Ribeiro
- Department of Sports, Douro Higher Institute of Educational Sciences, Penafiel, Portugal
| | - António J. Silva
- Research Centre in Sports Sciences, Health and Human Development, Vila Real, Portugal
- Department of Sports, Exercise and Health Sciences, University of Trás-os-Montes e Alto Douro, Vila Real, Portugal
| | - Tiago M. Barbosa
- Research Centre in Sports Sciences, Health and Human Development, Vila Real, Portugal
- Department of Sport Sciences, Instituto Politécnico de Bragança, Bragança, Portugal
| | - António M. Monteiro
- Research Centre in Sports Sciences, Health and Human Development, Vila Real, Portugal
- Department of Sport Sciences, Instituto Politécnico de Bragança, Bragança, Portugal
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Using Global Positioning System to Compare Training Monotony and Training Strain of Starters and Non-Starters across of Full-Season in Professional Soccer Players. SUSTAINABILITY 2022. [DOI: 10.3390/su14063560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Soccer is an attractive and popular team sport that has high physiological and fitness stress, and therefore requires special and controlled training programs during the season. The aim of this study was to describe the weekly average and changes in training monotony (TM) and training strain (TS) throughout different periods of the season in professional football players based on the number of accelerations and decelerations, and also to analyze the difference between starters and non-starters players in TM and TS. Nineteen professional players from a soccer team competing in the Iranian Premier League (age, 28 ± 4.6 years; height, 181.6 ± 5.8 cm; body mass, 74.5 ± 5.6 kg, and body mass index, 21.8 ± 1.0 kg/m2) participated in a cohort study. Participants were divided into two groups based on the time of participation in the weekly competition: starters (N = 10) or non-starters (N = 9). The physical activities of the players were recorded during the training sessions and competitive matches of 43 weeks using GPSPORTS systems Pty Ltd. During pre- and end-season TS was not significantly different between starters and non-starters, while during early- and mid-season starters showed a higher TS than non-starter (p < 0.05). TS was higher during early- and mid-season compared to pre- and end-season. In all zones on both the TM and TS variables, non-starters experienced higher change percentages and coefficient of variation. TM during the season in all zones of accelerations was not significantly different between starters and non-starters. while during mid-season starters showed a higher TM than non-starters in all zones of decelerations (p < 0.05). TM data showed fluctuations and w-shaped graphs in the week-by-week survey. These results indicate that training during early- and mid-season is not enough for the physical development of non-starters soccer players. Coaches should be more careful when designing training for non-starters players, and they could consider the use of game simulation, preparatory match or intra-team match, or individual training programs.
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Exploring interactions between maturity status and playing time with fluctuations in physical fitness and hormonal markers in youth soccer players. Sci Rep 2022; 12:4463. [PMID: 35296744 PMCID: PMC8927162 DOI: 10.1038/s41598-022-08567-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 02/25/2022] [Indexed: 11/24/2022] Open
Abstract
The purpose of this study was to determine the differences in functional capacities and hormonal indices according to biological maturity and seasonal playing time status in young soccer players. Twenty-three male under-15 players (14.6 ± 0.2 years) were divided into two groups, based on their maturity status and seasonal playing time. They were measured for anthropometrics, Yo-Yo intermittent recovery level 1 (YYIR1), seven repeated sprint test (7RST), countermovement jump (CMJ), skeletal age, growth hormone, and insulin-like growth factor-1 (IGF-1) level. Age at peak height velocity (APHV) was determined to estimate the maturity timing. The results revealed that players who advanced in maturation were significantly heavier (p = 0.029) and had higher values in skeletal age (p < 0.001), sitting height (p = 0.005), CMJ (p = 0.038), and IGF-1 (p = 0.013). Players given greater playing time exhibited significantly lower fatigue index (p = 0.012), but higher CMJ (p = 0.003) and IGF-1 (p = 0.001) values. The overall results highlighted that early-maturing players and players with greater playing time obtained higher values in both CMJ and IGF-1. The findings may provide an insight on the coaches’ evaluation of players and on the possible factors that may affect the future playing status of young male soccer players.
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Weekly Variations of Well-Being and Interactions with Training and Match Intensities: A Descriptive Case Study in Youth Male Soccer Players. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19052935. [PMID: 35270628 PMCID: PMC8910011 DOI: 10.3390/ijerph19052935] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 02/25/2022] [Accepted: 03/01/2022] [Indexed: 02/05/2023]
Abstract
The aim of this study was two-fold: (i) analyze the weekly variations of well-being and training/match intensity measures in youth soccer players, and (ii) test relations between well-being and training intensity outcomes. The study followed a descriptive case study design. Twenty-seven under-17 male soccer players were monitored for well-being and training intensity parameters over seventeen consecutive weeks. An adjusted version of the Hooper questionnaire was used to monitor the perceptive sleep quality, readiness, fatigue, and delayed onset muscle soreness (DOMS) early in the morning. The CR-10 Borg’s scale was also used for monitoring the rate of perceived exertion (RPE) of players after training sessions. Repeated-measures analysis of variance was executed to test the between-week variations of both well-being and training intensity outcomes. Moreover, Pearson product moment correlation was used to test the relations between well-being and training intensity outcomes. Repeated measures ANOVA revealed significant differences between weeks in the sleep quality (F = 0.422; p < 0.001; ηp2 = 0.140), readiness (F = 0.8.734; p < 0.001; ηp2 = 0.251), fatigue (F = 4.484; p < 0.001; ηp2 = 0.147), DOMS (F = 3.775; p = 0.001; ηp2 = 0.127), RPE (F = 7.301; p < 0.001; ηp2 = 0.219), and session-RPE (F = 17.708; p < 0.001; ηp2 = 0.405). Correlations between well-being and training intensity outcomes in the same week revealed moderate correlations between fatigue and session-RPE (r = 0.325). As conclusions, it was found that well-being and training intensity fluctuates over the season, while well-being outcomes seems to be related with training intensity, although with a small magnitude.
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Nobari H, Gandomani EE, Reisi J, Vahabidelshad R, Suzuki K, Volpe SL, Pérez-Gómez J. Effects of 8 Weeks of High-Intensity Interval Training and Spirulina Supplementation on Immunoglobin Levels, Cardio-Respiratory Fitness, and Body Composition of Overweight and Obese Women. BIOLOGY 2022; 11:biology11020196. [PMID: 35205063 PMCID: PMC8869481 DOI: 10.3390/biology11020196] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/24/2022] [Accepted: 01/24/2022] [Indexed: 12/13/2022]
Abstract
Simple Summary Overweight and obese, like other forms of malnutrition, have been shown to affect immune function through changing immunoglobin or cardio-respiratory fitness levels and cell-mediated immune responses. Although calorie restriction and exercise are the most common therapies for obesity or overweight, it is unclear what kind of supplementation these people should take or how much exercise they should perform. Hence, in this study, we examined the effect of 8 weeks of high-intensity interval training (HIIT) with spirulina supplementation on the humoral immunity, cardio-respiratory fitness, and body composition of overweight and obese women. The results demonstrated that spirulina supplementation with HIIT not only decreased fat free mass but also boosted immunoglobin-A, which plays an important role in the immune system. Abstract Our study examined the effect of 8 weeks of high-intensity interval training (HIIT) and spirulina supplementation on the humoral immunity, cardio-respiratory fitness, and body composition of overweight and obese women. Thirty sedentary women (height: 161.7 ± 2.8 cm, body mass: 75.8 ± 8.4 kg, body mass index [BMI]: 28.8 ± 2.5 kg/m2, age: 25.1 ± 6.7 years) were divided into three groups: placebo with HIIT group, spirulina group (SG), or combined group (CG). Exercise groups performed HIIT for 8 weeks, with three sessions per week and four to seven repetitions in each session of 30 s running and 30 s walking; the intensity was established at 90% of the maximum heart rate. Supplementation groups received 6 g of spirulina powder per day. Fasting blood samples were collected before and after 8 weeks to determine the concentrations of immunoglobulins (IgA and IgG). There was a significant group-by-time interaction for fat free mass (FFM; p = 0.001, f = 8.52, ηp2 = 0.39) and IgA (p = 0.036, f = 3.86, ηp2 = 0.22). The post hoc analysis revealed that CG reduced FFM significantly (p = 0.012, g = −0.55) after training. CG and SG showed significantly greater IgA concentrations after 8 weeks (p = 0.02, g = 0.70 and p = 0.001, g = 0.34, respectively). We conclude that spirulina supplementation with HIIT affects the body composition (lower FFM) but also boosts IgA, which plays an important role in the immune system.
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Affiliation(s)
- Hadi Nobari
- Department of Exercise Physiology, Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, Ardabil 56199-11367, Iran
- Department of Physiology, School of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan 81746-7344, Iran;
- Correspondence: (H.N.); (J.R.)
| | - Elham Eyni Gandomani
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan 81746-7344, Iran;
| | - Jalil Reisi
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan 81746-7344, Iran;
- Correspondence: (H.N.); (J.R.)
| | | | - Katsuhiko Suzuki
- Faculty of Sport Sciences, Waseda University, Saitama 359-1192, Japan;
| | - Stella Lucia Volpe
- Department of Human Nutrition, Foods and Exercise, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA;
| | - Jorge Pérez-Gómez
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain;
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Maturational effect on physical capacities and anabolic hormones in under-16 elite footballers: a cross-sectional study. SPORT SCIENCES FOR HEALTH 2021. [DOI: 10.1007/s11332-021-00806-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Abstract
Purpose
The purposes of this study were to describe the fitness and hormonal levels according to playing time (PT) (i.e., PT during season less (PT1) or more (PT2) than 50% of the total time) and maturation level (ML) (i.e., normal (ML1) and early maturity levels (ML2)), and to analyze the differences between groups for the measures of aerobic capacity, anaerobic power, power performance, and hormonal concentrations.
Methods
Twenty-four youth footballers of a U16 team participated in this study. Anthropometric measures, maturity status, growth hormone, insulin-like growth factor (IGF-1), maximal oxygen uptake, fatigue index, and countermovement jump were collected.
Results
Significant differences were found between both PT and ML groups for maturational status, aerobic capacity, power performance, and IGF1 concentrations. The interaction of PT and ML revealed significant differences for maturity offset and power performance. When using the skeletal age as a covariant, the previously significant differences found were reduced only to the fatigue index measure.
Conclusions
The response variables analyzed in the present study seem to be influenced by PT and ML. This must be considered when planning training, and coaches must be sensible to these effects as they may assume a preponderant role in PT.
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Nobari H, Kharatzadeh M, Khalili SM, Pérez-Gómez J, Ardigò LP. Fluctuations of Training Load Variables in Elite Soccer Players U-14 throughout the Competition Season. Healthcare (Basel) 2021; 9:healthcare9111418. [PMID: 34828465 PMCID: PMC8623611 DOI: 10.3390/healthcare9111418] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 10/10/2021] [Accepted: 10/16/2021] [Indexed: 11/17/2022] Open
Abstract
Excessive daily training load (TL) can affect the musculoskeletal system health of youth elite soccer players. The purposes of this study were (i) to describe the TL and session rating of perceived exertion (s-RPE) throughout the competition season; (ii) to analyze the weekly (w) differences of acute (daily) workload (wAWL), chronic workload (wCWL), acute–chronic workload ratio, training monotony (wTM), and training strain (wTS) among three periods over the season (early-, mid-, and end-season) by playing position; and (iii) to compare the TL variables during competition periods for the whole team. Twenty young elite soccer players in the under-14 category participated in this study. The game positions were considered as six wide defenders and wide midfielders (WM), five central defenders and central midfielders, and four strikers (ST). Daily monitoring was continued for 26 weeks during a full competition season. According to the league schedule, the season was divided into three periods: early-season from w1 to w8, mid-season from w9 to w17, and end-season from w18 to w26. The main results were that the higher TLs were detected in the early- and mid-season. There was a wAWL and wCWL decrease for all playing positions from early- to mid- and end-season, but the wCWL change was significant only from early- to mid-season (p ≤ 0.05). For all playing positions but ST, there was a considerable wTM increase from early- to mid-season. When compared with all other playing positions in terms of wAWL and wCWL, WM showed significantly greater values (p ≤ 0.05). Throughout the season periods, all workload indicators showed a considerable reduction, although there was a significant increase in the three other workload-derived variables (all with p ≤ 0.05) and namely: (i) wACWLR from mid- to end-season; (ii) wTM from early- to mid- and end-season; and (iii) wTS from early- to mid-season. Daily training load and s-RPE had significant fluctuations during all macrocycles of the competition season (p ≤ 0.05). In addition, in the mid-season, wTM and wTS were higher. Training load monitoring (in terms of, e.g., wAWL, wCWL, and s-RPE) could be the key for coaches of soccer teams to prevent overtraining and injury, especially in U-14 players, who are more susceptible to being affected by high workload.
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Affiliation(s)
- Hadi Nobari
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain; (S.M.K.); (J.P.-G.)
- Department of Physical Education and Sports, University of Granada, 18010 Granada, Spain
- Department of Exercise Physiology, Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, Ardabil 56199-11367, Iran
- Sports Scientist, Sepahan Football Club, Isfahan 81887-78473, Iran
- Correspondence: (H.N.); (L.P.A.)
| | - Masoud Kharatzadeh
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan 81746-7344, Iran;
| | - Sara Mahmoudzadeh Khalili
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain; (S.M.K.); (J.P.-G.)
- Department of Health and Sport Rehabilitation, Faculty of Sport Sciences and Health, Shahid Beheshti University, Tehran 198396-3113, Iran
| | - Jorge Pérez-Gómez
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain; (S.M.K.); (J.P.-G.)
| | - Luca Paolo Ardigò
- Department of Neurosciences, Biomedicine and Movement Sciences, School of Exercise and Sport Science, University of Verona, 37131 Verona, Italy
- Correspondence: (H.N.); (L.P.A.)
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Nobari H, Cholewa JM, Castillo-Rodríguez A, Kargarfard M, Pérez-Gómez J. Effects of chronic betaine supplementation on performance in professional young soccer players during a competitive season: a double blind, randomized, placebo-controlled trial. J Int Soc Sports Nutr 2021; 18:67. [PMID: 34663363 PMCID: PMC8525016 DOI: 10.1186/s12970-021-00464-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 10/02/2021] [Indexed: 01/28/2023] Open
Abstract
OBJECTIVE Various nutritional strategies are adopted for athletes to maintain and to improve performance during the competition season. Betaine may enhance performance during a competitive season by increasing the testosterone to cortisol ratio and reducing systemic inflammation. The aim of this study was to investigate the effect of betaine supplementation on the bio-motor abilities in young professional soccer players. METHODS Twenty-nine young professional soccer players (age, 15.5±0.3 years) were matched by position and randomly assigned to one of two groups for 14 weeks: betaine (BG, 2 g/day; n=14) or placebo (PG n=15). Diet was standardized by a nutritionist, and measures of muscular power (countermovement jump: CMJ), change of direction: modified 5-0-5), acceleration (10 m sprint), sprint performance (30 m sprint time: SpT), muscular strength (leg press and bench press one repetition maximum: 1-RM), repeated sprint ability (running-based anaerobic sprint test: RAST), and aerobic capacity (30-15 intermittent fitness test) were assessed in the pre (P1), mid (P2) and post (P3) season over the course of 5 days. All subjects participated in one soccer match and five training sessions per week. RESULTS Significant (p < 0.05) group x time interactions were found for maximal oxygen uptake (VO2max), anaerobic peak power, and muscular strength favoring BG at P2 and P3 compared to P1. There were meaningful (p < 0.05) group x time interactions for CMJ, SpT, and peak power during the RAST that favored the BG. CONCLUSIONS 14-week of betaine supplementation increased predicted 1-RM, VO2max, and repeated sprint ability performance in youth professional soccer players. Betaine supplementation seems to be a useful nutritional strategy to improve and to maintain performance during a competitive soccer season.
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Affiliation(s)
- Hadi Nobari
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, 81746- 7344, Isfahan, Iran.
- Department of Exercise Physiology, Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, 56199-11367, Ardabil, Iran.
| | - Jason M Cholewa
- Department of Exercise Physiology, College of Health Sciences, University of Lynchburg, 24501, Lynchburg, VA, USA
| | | | - Mehdi Kargarfard
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, 81746- 7344, Isfahan, Iran
| | - Jorge Pérez-Gómez
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, 10003, Cáceres, Spain
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Nobari H, Alves AR, Clemente FM, Pérez-Gómez J. Influence of 2D:4D ratio on fitness parameters and accumulated training load in elite youth soccer players. BMC Sports Sci Med Rehabil 2021; 13:125. [PMID: 34635156 PMCID: PMC8504125 DOI: 10.1186/s13102-021-00354-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 09/28/2021] [Indexed: 11/10/2022]
Abstract
BACKGROUND Digit ratio (2D:4D) characterized by the length of the second digit (2D) divided by the length of the fourth digit (4D), is a powerful marker of athletic performance. Some studies showed a negative correlation between 2D:4D ratio and sports performances. OBJECTIVES The purpose of the present study was three-fold: (1) to analyze the influence of anthropometric and 2D:4D ratio on variations of accumulated training load (ATL) and fitness parameters: maximal oxygen uptake (V̇O2max), countermovement jump (CMJ), isometric muscular strength of the knee extensor for hamstring (ISH) and flexor for quadriceps (ISQ) muscles; along three stages of evaluation of soccer players based on playing positions; (2) to analyze the correlations between 2D:4D ratio and aforementioned parameters; and (3) to investigate if variance in fitness levels and ATL can explain the 2D:4D ratio. METHODS Twenty-four elite players under 17 years were daily monitored for their rating perceived exertion and ATL across 24 weeks over the season. Soccer players have also measured in three stages for anthropometric traits and fitness parameters. RESULTS Significant differences were observed between playing positions for body mass, goalkeepers had higher body mass compared to centre-midfielder and winger players. Moreover, there were significant differences in ATL between early-season to mid-season in goalkeepers (P = 0.032). The 2D:4D ratio (left and right) shown largely and negatively association with muscular strength (ISQ: r = - 0.80; r = - 0.78, P ≤ 0.001, ISH: r = - 0.63; r = - 0.62, P = 0.001, respectively) and VO2max changes (r = - 0.55, P = 0.005; r = - 0.50, P = 0.013, respectively); lastly, both 2D:4D ratio significantly predicted changes in muscular strength and VO2max in young soccer players. CONCLUSIONS Goalkeepers tended to have higher body mass compared to centre-midfielder and winger players; and 2D:4D ratio revealed a mighty predictor of physical fitness changes in soccer players. Evidence should be helpful to professionals to highlight the usefulness of the 2D:4D into the identification of talent, but also to optimize young players' performance.
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Affiliation(s)
- Hadi Nobari
- Department of Exercise Physiology, Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, 56199-11367, Ardabil, Iran. .,Sports Scientist, Sepahan Football Club, 81887-78473, Isfahan, Iran.
| | - Ana Ruivo Alves
- Department of Arts, Humanities and Sport, Polytechnic Institute of Beja, 7800-295, Beja, Portugal.,Research Center in Sport Sciences, Health Sciences and Human Development, CIDESD, 5001-801, Vila Real, Portugal
| | - Filipe Manuel Clemente
- Escola Superior Desporto e Lazer, Instituto Politécnico de Viana do Castelo, Rua Escola Industrial Comercial de Nun'Álvares, 4900-347, Viana do Castelo, Portugal.,Instituto de Telecomunicações, Delegação da Covilhã, 1049-001, Lisboa, Portugal
| | - Jorge Pérez-Gómez
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, 10003, Cáceres, Spain
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Nobari H, Mainer-Pardos E, Adsuar JC, Franco-García JM, Rojo-Ramos J, Cossio-Bolaños MA, Urzua Alul L, Pérez-Gómez J. Association Between Endocrine Markers, Accumulated Workload, and Fitness Parameters During a Season in Elite Young Soccer Players. Front Psychol 2021; 12:702454. [PMID: 34531792 PMCID: PMC8438147 DOI: 10.3389/fpsyg.2021.702454] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 07/28/2021] [Indexed: 01/26/2023] Open
Abstract
The purpose of this study was to analyze differences between endocrine markers in soccer players, based on playing positions, and correlations between endocrine markers (testosterone, cortisol, growth hormone, and insulin-like growth factor-1), with accumulated workload training and fitness parameters [maximal oxygen uptake (VO2max), countermovement jump (CMJ), and isometric maximal strength (1-RM) of the knee for hamstring (ISH) and quadriceps (ISQ) muscles] during early-, mid-, and end-seasons. Twenty-four elite soccer players under 17 participated in this study. The results showed that there was no difference between levels of the endocrine markers among the different positions of the players. Significant correlations were observed between endocrines parameters and fitness performance (ISQ, ISH, VO2max, and CMJ). Regression analysis showed that 1-RM and VO2max were the best predictors of endocrine markers. These findings demonstrated that the activity profiles of youth soccer players were not influenced by endocrine markers. Also, it may be assumed that endocrines levels can be used to better explain the physical capacities of this population. Finally, endocrines markers may help to predict changes in 1-RM and VO2max.
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Affiliation(s)
- Hadi Nobari
- Department of Physical Education and Sports, University of Granada, Granada, Spain
- Health, Economy, Motricity and Education Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan, Iran
- Sports Scientist, Sepahan Football Club, Isfahan, Iran
| | | | - José Carmelo Adsuar
- Health, Economy, Motricity and Education Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain
| | - Juan Manuel Franco-García
- Health, Economy, Motricity and Education Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain
| | - Jorge Rojo-Ramos
- Health, Economy, Motricity and Education Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain
| | | | - Luis Urzua Alul
- Escuela de Kinesiología, Facultad de Salud, Universidad Santo Tomás, Santiago, Chile
| | - Jorge Pérez-Gómez
- Health, Economy, Motricity and Education Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain
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Mainer-Pardos E, Gonzalo-Skok O, Nobari H, Lozano D, Pérez-Gómez J. Age-related differences in linear sprint in adolescent female soccer players. BMC Sports Sci Med Rehabil 2021; 13:97. [PMID: 34420519 PMCID: PMC8381494 DOI: 10.1186/s13102-021-00327-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 08/12/2021] [Indexed: 11/12/2022]
Abstract
Background Several studies have observed the contribution of chronological age, biological maturation, and anthropometric characteristics to sprinting performance in young soccer players. Nevertheless, there are no studies that have analysed the contribution of these characteristics to running speed qualities in adolescent female soccer players. Objective This study investigated age-related differences in sprint performance in adolescent female soccer players. Also, it examined the possible influence of anthropometry [body mass and body mass index (BMI)] and biological maturation [age at peak height velocity (APHV)] in sprint performance. Methods Eighty adolescent female soccer players [under (U) 14, n = 20; U16, n = 37; U18, n = 23] participated in this study. Players were tested for 40 m sprint (each 10 m split times). Results Posthoc analysis revealed better performance in all split sprint times of older soccer players (U18 and U16) compared with younger category (F: 3.380 to 6.169; p < 0.05; ES: 0.64 to 1.33). On the contrary in all split sprint times, there were no significant changes between U16 and U18 (p < 0.05; ES: 0.03 to 0.17). ANCOVA revealed differences in all parameters between groups, controlled for APHV (p < 0.05). In contrast, all between-group differences disappeared after body mass and BMI adjustment (p > 0.05). Finally, the results indicate that BMI and body mass were significantly correlated with 40 m sprint (p < 0.05; r: -0.31) and 20 m flying (p < 0.01; r: 0.38), respectively. Conclusion In the present players’ sample, body mass and BMI had a significant impact on running speed qualities.
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Affiliation(s)
- Elena Mainer-Pardos
- Health Sciences Faculty, Universidad San Jorge, Autov A23 km 299, 50830, Villanueva de Gállego, Zaragoza, Spain
| | | | - Hadi Nobari
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, 81746-7344, Isfahan, Iran. .,Sports Scientist, Sepahan Football Club, 81887-78473, Isfahan, Iran.
| | - Demetrio Lozano
- Health Sciences Faculty, Universidad San Jorge, Autov A23 km 299, 50830, Villanueva de Gállego, Zaragoza, Spain
| | - Jorge Pérez-Gómez
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, 10003, Cáceres, Spain
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Nobari H, Cholewa JM, Pérez-Gómez J, Castillo-Rodríguez A. Effects of 14-weeks betaine supplementation on pro-inflammatory cytokines and hematology status in professional youth soccer players during a competition season: a double blind, randomized, placebo-controlled trial. J Int Soc Sports Nutr 2021; 18:42. [PMID: 34090451 PMCID: PMC8180114 DOI: 10.1186/s12970-021-00441-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 05/12/2021] [Indexed: 12/13/2022] Open
Abstract
Objective Systemic elevations in pro-inflammatory cytokines are a marker of non-functional over reaching, and betaine has been shown to reduce the secretion of pro-inflammatory cytokines in vitro. The aim of this study was to investigate the effects of betaine supplementation on tumor necrosis factor alpha (TNF-α), interleukins-1 beta (IL-1β), − 6 (IL-6) and the complete blood cell (CBC) count in professional youth soccer players during a competitive season. Methods Twenty-nine soccer players (age, 15.5 ± 0.3 years) were randomly divided into two groups based on playing position: betaine group (BG, n = 14, 2 g/day) or placebo group (PG, n = 15). During the 14-week period, training load was matched and well-being indicators were monitored daily. The aforementioned cytokines and CBC were assessed at pre- (P1), mid- (P2), and post- (P3) season. Results Significant (p < 0.05) group x time interactions were found for TNF-α, IL-1β, and IL-6. These variables were lower in the BG at P2 and P3 compared to P1, while IL-1β was greater in the PG at P3 compared to P1 (p = 0.033). The CBC count analysis showed there was significant group by time interactions for white blood cells (WBC), red blood cells (RBC), hemoglobin (Hb), and mean corpuscular hemoglobin concentration (MCHC). WBC demonstrated increases at P3 compared to P2 in PG (p = 0.034); RBC was less at P3 compared to P1 in BG (p = 0.020); Hb was greater at P2 compared to P1, whilst it was less at P3 compared to P3 for both groups. MCHC was greater at P3 and P2 compared to P1 in BG, whereas MCHC was significantly lower at P3 compared to P2 in the PG (p = 0.003). Conclusion The results confirmed that 14 weeks of betaine supplementation prevented an increase in pro-inflammatory cytokines and WBC counts. It seems that betaine supplementation may be a useful nutritional strategy to regulate the immune response during a fatiguing soccer season.
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Affiliation(s)
- Hadi Nobari
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan, 81746-7344, Iran.
| | - Jason M Cholewa
- Department of Exercise Physiology, College of Health 587 Sciences, University of Lynchburg, Lynchburg, 24501, VA, USA
| | - Jorge Pérez-Gómez
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, 10003, Spain
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Comparison of Knee and Hip Kinematics during Landing and Cutting between Elite Male Football and Futsal Players. Healthcare (Basel) 2021; 9:healthcare9050606. [PMID: 34070221 PMCID: PMC8158683 DOI: 10.3390/healthcare9050606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 05/03/2021] [Accepted: 05/13/2021] [Indexed: 11/24/2022] Open
Abstract
To design an accurate sport injury prevention program, alterations in the knee and hip kinematic variables involved in injury mechanisms should be known. The main purpose of the current study was to compare knee and hip kinematic variables during landing and cutting among male football and futsal players, and to discuss them within an injury description frame. Twenty football (20.5 ± 2.1 years., 74.5 ± 6.9 kg and 1.79 ± 0.07 m) and twenty futsal players (20.3 ± 2.0 years., 73.5 ± 7.1 kg and 1.78 ± 0.07 m), with at least three years’ experience of playing in the Kerman Province League, participated in this study. Hip flexion, knee flexion and knee valgus angle during two main movements with risk of injury, such as landing and cutting, were measured using a motion capture system with passive markers at 120-Hz sampling frequency. Landing and cutting maneuvers were administered in as natural way as possible. Results showed significant differences in landing and cutting maneuvers between groups in hip flexion, knee flexion and knee valgus angle. Results indicated that footballers have less extension of hip and knee joints than futsal players in landing maneuvers, which may be due to the higher requirement of jumping−landing maneuvers when playing football. In cutting maneuvers, footballers showed less hip and knee flexion than futsal players, whereas the knee valgus angle in cutting maneuvers was lower in futsal players. More information on the injury mechanisms of landing and cutting in football and futsal are needed to improve the design of injury prevention programs.
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Fluctuations in Well-Being Based on Position in Elite Young Soccer Players during a Full Season. Healthcare (Basel) 2021; 9:healthcare9050586. [PMID: 34069245 PMCID: PMC8156560 DOI: 10.3390/healthcare9050586] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/09/2021] [Accepted: 05/13/2021] [Indexed: 01/25/2023] Open
Abstract
The current study surveyed weekly and daily variations of well-being ratings relative to the Hooper Index (HI): fatigue (wFatigue), stress (wStress), delayed onset muscle soreness (wDOMS), and sleep quality (wSleep) during a soccer season based on players’ positions. The full-season was divided into three meso-cycles: Early season, week (W)1 to W7; Mid-season, W8 to W13, and End-season, W14 to W20. Twenty-six young players participated in the study (age, 15.5 ± 0.2 years; height, 172.9 ± 4.2 cm; body mass, 61.4 ± 5.6 kg; body fat, 8.6 ± 2.9%; VO2max, 48.4 ± 2.4 mL.kg−1·min−1; maturity offset, 1.9 ± 0.3 years). Participants played in the same team and competed in Iran national under-16 competitions. Well-being status was monitored on training days using the HI questionnaire. The main result was a significant difference between well-being status 5 days before match day (MD) and 4 days before MD, compared to MD for all playing positions (p ≤ 0.001). The highest and lowest records occurred during End-season for wDOMS (strikers = 11.5 ± 8.4 arbitrary units (AU)), Early season (central defenders = 9.5 ± 0.7 AU) and for wFatigue (central midfielders = 11.4 ± 0.9 AU), and Early season (wide defenders = 9.7 ± 0.7 AU), respectively. Overall, the results showed a significant increase in wStress and wSleep for all players’ positions from Early- to End-season. The main application of this study is to make coaches aware of their players’ well-being fluctuations throughout the full season, especially in young elite soccer players, and to avoid injuries, overtraining, and overreaching as much as possible.
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Somatotype, Accumulated Workload, and Fitness Parameters in Elite Youth Players: Associations with Playing Position. CHILDREN-BASEL 2021; 8:children8050375. [PMID: 34068574 PMCID: PMC8151242 DOI: 10.3390/children8050375] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 04/28/2021] [Accepted: 05/06/2021] [Indexed: 11/16/2022]
Abstract
The purpose of this study was three-fold: (1) to describe anthropometric, maturation, and somatotype differences of players based on playing positions; (2) to analyze variations of accumulated load training (AcL) and fitness parameters between playing positions; and finally (3) to explain the variation of maximal oxygen uptake (VO2max) and peak power (PP) through the AcL, body fat (BF), maturity, somatotype and fitness levels. Twenty-seven male youth soccer players under-16 were divided by the following positions participated in this study: six central midfielders, four wingers (WG), five forwards, eight defenders, and four goalkeepers (GK). They were evaluated on two occasions: pre-season and after-season. Height, sitting height, body mass, BF, girths, percentage of BF (BF%), lean body mass, maturity, somatotype, sprint test, change of direction test, Yo-Yo intermittent recovery test level 1, Wingate, PP, VO2max and fatigue index were assessed. Then, AcL was monitored during training sessions. The main results revealed significant differences between player positions for maturity offset (p = 0.001), for BF (p = 0.006), BF% (p = 0.015), and lean body mass kg (p = 0.003). Also, there were significant differences for AcL and fatigue index in pre-season between player positions (p < 0.05). In addition, there were some significant differences in pre- and after-season for VO2max and PP between player positions (p < 0.05). In conclusion, GK showed higher values in anthropometric, body composition variables and maturity offset compared to the other positions, while WG presented lower levels of BF. In pre-season, there were more differences by player positions for the different variables analyzed than after-season that reinforces the tactical role of the positions, and the emphasis in increased load in the beginning of the season. This study could be used by coaches, staff, and researchers as a reference for athletes of the same sex, age, and competitive level.
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Nobari H, Vahabidelshad R, Pérez-Gómez J, Ardigò LP. Variations of Training Workload in Micro- and Meso-Cycles Based on Position in Elite Young Soccer Players: A Competition Season Study. Front Physiol 2021; 12:668145. [PMID: 33995127 PMCID: PMC8117006 DOI: 10.3389/fphys.2021.668145] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 03/29/2021] [Indexed: 12/29/2022] Open
Abstract
The objectives of this study were to quantify the matches and training workload in micro-cycles of an elite young soccer team considering field position and to explain meso-cycles based on change of weekly acute (wAWL), chronic load (wCWL), acute-to-chronic workload ratio, training monotony (wTM), and training strain (wTS) between early-, mid-, and end-season periods considering playing position and whole team. Twenty-six under-16 elite young soccer players participated in this study, including six wide defenders and wide midfielders (WM), five central defenders (CD) and central midfielders, and four strikers (ST). Daily monitoring was performed by players for 20 weeks with the rating of perceived exertion using the Borg CR-10 scale. In comparison with early-season, results showed that there was a significant increase, in all playing positions, in wAWL and wCWL (except ST) and in wTM (except CD and ST) compared with end-season. On the other hand, there were significant reductions in wTS in CD, WM, and ST at the end-season. According to the results, coaches should consider the field position in different situations. Differences between training workload and matches can be a good guide for coaches, who have a special understanding of what causes the most load in training programs. Excessive training workload can potentially cause injury to adolescent athletes and controlling wTM can prevent this.
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Affiliation(s)
- Hadi Nobari
- Department of Physical Education and Sports, University of Granada, Granada, Spain.,HEME Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain.,Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan, Iran.,Sports Scientist, Sepahan Football Club, Isfahan, Iran.,Faculty of Motor Sciences, Université libre de Bruxelles, Brussels, Belgium
| | - Reyhaneh Vahabidelshad
- Sports Scientist, Sepahan Football Club, Isfahan, Iran.,Faculty of Motor Sciences, Université libre de Bruxelles, Brussels, Belgium
| | - Jorge Pérez-Gómez
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain
| | - Luca Paolo Ardigò
- School of Exercise and Sport Science, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
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Nobari H, Alves AR, Haghighi H, Clemente FM, Carlos-Vivas J, Pérez-Gómez J, Ardigò LP. Association between Training Load and Well-Being Measures in Young Soccer Players during a Season. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18094451. [PMID: 33922250 PMCID: PMC8122726 DOI: 10.3390/ijerph18094451] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/16/2021] [Accepted: 04/21/2021] [Indexed: 02/07/2023]
Abstract
This study aimed to analyze the correlations among weekly (w) acute workload (wAW), chronic workload (wCW), acute/chronic workload ratio (wACWR), training monotony (wTM), training strain (wTS), sleep quality (wSleep), delayed onset muscle soreness (wDOMS), fatigue (wFatigue), stress (wStress), and Hooper index (wHI) in pre-, early, mid-, and end-of-season. Twenty-one elite soccer players (age: 16.1 ± 0.2 years) were monitored weekly on training load and well-being for 36 weeks. Higher variability in wAW (39.2%), wFatigue (84.4%), wStress (174.3%), and wHI (76.3%) at the end-of-season were reported. At mid-season, higher variations in wSleep (59.8%), TM (57.6%), and TS (111.1%) were observed. Moderate to very large correlations wAW with wDOMS (r = 0.617, p = 0.007), wFatigue, wStress, and wHI were presented. Similarly, wCW reported a meaningful large association with wDOMS (r = 0.526, p < 0.001); moderate to very large associations with wFatigue (r = 0.649, p = 0.005), wStress, and wHI. Moreover, wTM presented a large correlation with wSleep (r = 0.515, p < 0.001); and a negatively small association with wStress (r = −0.426, p = 0.003). wTS showed a small to large correlation with wSleep (r = 0.400, p = 0.005) and wHI; also, a large correlation with wDOMS (r = 0.556, p = 0.028) and a moderate correlation with wFatigue (r = 0.343, p = 0.017). Wellness status may be considered a useful tool to provide determinant elite players’ information to coaches and to identify important variations in training responses.
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Affiliation(s)
- Hadi Nobari
- Department of Physical Education and Sports, University of Granada, 18010 Granada, Spain
- Sports Scientist, Sepahan Football Club, Isfahan 81887-78473, Iran
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan 81746-7344, Iran
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain;
- Correspondence: (H.N.); (J.P.-G.)
| | - Ana Ruivo Alves
- Department of Arts, Humanities and Sports, Polytechnic Institute of Beja, School of Education, 7800-295 Beja, Portugal;
- Research Center in Sports Sciences, Health Sciences and Human Development, CIDESD, 5001-801Vila Real, Portugal
- Laboratory of Physical Activity and Health, Polytechnic Institute of Beja, School of Education, 7800-295 Beja, Portugal
| | - Hamed Haghighi
- Department of Sport Injuries and Corrective Exercises, Faculty of Sport Sciences, University of Isfahan, Isfahan 81746-7344, Iran;
| | - Filipe Manuel Clemente
- Polytechnic Institute of Viana do Castelo, School of Sport and Leisure, 4900-347 Viana do Castelo, Portugal;
- Institute of Telecommunications, IT-Branch Covilhã, 6200-001 Covilhã, Portugal
| | - Jorge Carlos-Vivas
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain;
| | - Jorge Pérez-Gómez
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain;
- Correspondence: (H.N.); (J.P.-G.)
| | - Luca Paolo Ardigò
- Department of Neurosciences, Biomedicine and Movement Sciences, School of Exercise and Sport Science, University of Verona, 37134 Verona, Italy;
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Nobari H, Fani M, Clemente FM, Carlos-Vivas J, Pérez-Gómez J, Ardigò LP. Intra- and Inter-week Variations of Well-Being Across a Season: A Cohort Study in Elite Youth Male Soccer Players. Front Psychol 2021; 12:671072. [PMID: 33897575 PMCID: PMC8062971 DOI: 10.3389/fpsyg.2021.671072] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 03/09/2021] [Indexed: 12/20/2022] Open
Abstract
This study describes the weekly variations of well-being ratings relative to fatigue (wFatigue), stress (wStress), delayed-onset muscle soreness (wDOMS), sleep quality (wSleep), and Hooper questionnaire (wHQ) throughout the season. In addition, the well-being variables for the playing position in different moments of the season were discussed. Twenty-one elite young soccer players U17 took part in this study. From the beginning of the pre-season, well-being status was monitored daily by the HQ method throughout 36 weeks, including four periods: (1) pre-season, (2) early-season, (3) mid-season, and (4) end-season. Players trained at least 3 times per week throughout the season. The main outcome was that, in weeks 33 and 28, the highest [wFatigue: 15.85 ± 3.38 arbitrary units (AU); wHQ: 48.86 ± 9.23 AU] and the lowest (wFatigue: 5.38 ± 1.88 AU; wHQ: 20.43 ± 5.49 AU) wFatigue and wHQ occurred, respectively, although the lowest level of wDOMS happened in week 28 (4.86 ± 2.15 AU), while the highest wDOMS was observed in week 5 (14.65 ± 4.16 AU). The highest wSleep (13.00 ± 2.12 AU) and wStress (11.65 ± 2.92 AU) were observed in weeks 8 and 34, respectively, while the lowest wSleep (5.81 ± 2.29 AU) and wStress (3.76 ± 0.94 AU) were marked in week 29 coincidentally. In the HQ between every weekday, except recovery day, and the day of the match (MD), considerable highest HQ was only revealed in 2 days after MD in contrast to overall team comparison. In the present study, we observed that the well-being changes between different phases of the season as well as between weeks and days of the week with the MD are significant. These results provide a great point of view for coaches and practitioners about well-being variations over a season in elite youth soccer level. As a result, coaches will be more aware about non-functional overreaching and taking measures to prevent it.
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Affiliation(s)
- Hadi Nobari
- Department of Physical Education and Sports, University of Granada, Granada, Spain.,HEME Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain.,Sepahan Football Club, Isfahan, Iran
| | - Maryam Fani
- Department of Biological Sciences in Sport and Health, Faculty of Sports Sciences and Health, Shahid Beheshti University, Tehran, Iran
| | - Filipe Manuel Clemente
- Escola Superior Desporto e Lazer, Instituto Politécnico de Viana Do Castelo, Rua Escola Industrial Comercial de Nun'Álvares, Viana Do Castelo, Portugal
| | - Jorge Carlos-Vivas
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain
| | - Jorge Pérez-Gómez
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain
| | - Luca Paolo Ardigò
- Department of Neurosciences, Biomedicine and Movement Sciences, School of Exercise and Sport Science, University of Verona, Verona, Italy
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Nobari H, Silva R, Clemente FM, Akyildiz Z, Ardigò LP, Pérez-Gómez J. Weekly Variations in the Workload of Turkish National Youth Wrestlers: A Season of Complete Preparation. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18073832. [PMID: 33917536 PMCID: PMC8038824 DOI: 10.3390/ijerph18073832] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/25/2021] [Accepted: 04/04/2021] [Indexed: 01/29/2023]
Abstract
The aim of this study was twofold: (1) to describe the weekly acute workload (wAW), chronic workload (wCW), acute/chronic workload ratio (wACWR), training monotony (wTM), and strain (wTS) across the preparation season (PS), and (2) to analyze the variations of wAW, wCW, wACWR, wTM, and training strain (wTS) between periods of PS (early-, mid-, and end). Ten elite young wrestlers were monitored daily during the 32 weeks of the season. Internal loads were monitored using session rating of perceived exertion, and weekly workload measures of wACWR, wTM, and wTS were also calculated. Results revealed that the greatest differences were found between early- and mid-PS for wAW (p = 0.004, g = 0.34), wCW (p = 0.002, g = 0.90), wTM (p = 0.005, g = 0.39), and wTS (p = 0.009, g = -1.1), respectively. The wACWR showed significant differences between early- and end-PS (p ≤ 0.001, g = -0.30). We concluded that wAW, wCW, and wTM are slightly lower during the first weeks of the PS. The wTM remained relatively high during the entire season, while wAW and wCW remained balanced throughout the PS. The greatest workload changes seem to happen from the early to mid-PS season.
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Affiliation(s)
- Hadi Nobari
- Department of Physical Education and Sports, University of Granada, 18010 Granada, Spain
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan 81746-7344, Iran
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain;
- Correspondence: (H.N.); (L.P.A.)
| | - Rui Silva
- Escola Superior Desporto e Lazer, Instituto Politécnico de Viana do Castelo, Rua Escola Industrial e Comercial de Nun’Álvares, 4900-347 Viana do Castelo, Portugal; (R.S.); (F.M.C.)
| | - Filipe Manuel Clemente
- Escola Superior Desporto e Lazer, Instituto Politécnico de Viana do Castelo, Rua Escola Industrial e Comercial de Nun’Álvares, 4900-347 Viana do Castelo, Portugal; (R.S.); (F.M.C.)
- Instituto de Telecomunicações, Delegação da Covilhã, 1049-001 Lisboa, Portugal
| | - Zeki Akyildiz
- Movement and Training Science Department, Gazi University, 06560 Ankara, Turkey;
| | - Luca Paolo Ardigò
- Department of Neurosciences, Biomedicine and Movement Sciences, School of Exercise and Sport Science, University of Verona, 37129 Verona, Italy
- Correspondence: (H.N.); (L.P.A.)
| | - Jorge Pérez-Gómez
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain;
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Associations between Inter-Limb Asymmetries in Jump and Change of Direction Speed Tests and Physical Performance in Adolescent Female Soccer Players. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18073474. [PMID: 33801592 PMCID: PMC8037528 DOI: 10.3390/ijerph18073474] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/24/2021] [Accepted: 03/25/2021] [Indexed: 11/17/2022]
Abstract
The association between asymmetries in jump and change of direction (COD) with physical performance in several sports show inconclusive results. The purposes of this study were to: (1) measure inter-limb asymmetries in three distinct groups in adolescent female soccer players and, (2) to determine the association between inter-limb asymmetries and physical performance in different age groups. Fifty-four players were distributed in three age groups: U-18, U-16 and U-14. All of them performed a series of jumps, sprints and change of direction speed tests. Asymmetries were assessed as the percentage difference between limbs, with the equation: 100/Max value (right and left) * in value (right and left) * -1 + 100. Mean inter-limb asymmetries were 2.91%, 4.82% and 11.6% for 180° COD, single leg hop and single leg countermovement jump tests respectively, but higher percentages of asymmetries were observed in many players individually. U-18 and U-16 showed significant differences on 180° left COD compared to U-14. Effect size (ES): 0.80 and 0.74, respectively; U-18 presented differences on single left leg hop test compared to U-14, ES: -0.72; U-16 also showed differences on 40 m speed compared to U-14, ES 0.87 (All p < 0.05). Jumping and COD physical tests show asymmetries in adolescent female soccer players, but these asymmetries do not interfere with physical performance. The largest asymmetry was observed in the single leg countermovement jump, and no asymmetries between groups were found. Due to the high variability in the direction of asymmetries, it is recommended to consider players' individual asymmetries for designing specific training programs.
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Nobari H, Barjaste A, Haghighi H, Clemente FM, Carlos-Vivas J, Perez-Gomez J. Quantification of training and match load in elite youth soccer players: a full-season study. J Sports Med Phys Fitness 2021; 62:448-456. [PMID: 33768776 DOI: 10.23736/s0022-4707.21.12236-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND The present study aimed to quantify training and match load in elite young soccer players over the course of an entire season. METHODS Using a longitudinal design, session-rate of perceived exertion (s-RPE) and its metrics [weekly acute workload (wAW), acute to chronic workload ratio (wACWR), training monotony and training strain] were examined in twenty-one elite young soccer players (mean±standard deviation; age, 16.1±0.2 years; height, 176.8±5.6 cm; body mass, 67.3±5.7 kg; BMI, 21.5±1.4 kg/m2; VO2max, 47.6±3.8 ml.kg-1.min-1) during the whole season containing 4 meso-cycles: Pre-season (Pre-S), Earlyseason (Ear-S), Mid-season (Mid-S), and End-season (End-S). RESULTS Repeated-measures analysis of variance examined variations in s-RPE load data across the 4 meso-cycles and 1-week of micro-cycle. Analyzing data revealed the End-S had a significant greater wAW compared to Early-S (p = 0.002, g = 0.96) and Mid-S (p < 0.001, g = 1.09). However, no differences between in-season periods were observed in wACWR (p = 0.524). The within-week variations revealed significant lower wAW in pre-match a day (MD-1) (p < 0.001), 1 day after match (MD+1) (p < 0.001) and 2 days after match (MD+2) (p < 0.001) compared to match day (MD) for overall team analysis. Additionally, analyses by playing position showed that fullbacks have a significant lower AW in MD+2 compared to MD (p < 0.029). CONCLUSIONS The periodization of training load indicated variations across the whole season in young elite players. The weekly micro-cycle perceived load could be identified as follows; there are higher training loads on MD-3 and MD-2 which was similar to intensities experienced by players throughout the match play and, furthermore, lower overall WL on the MD+1 and MD+2 in order to ensure the optimal recovery of the players.
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Affiliation(s)
- Hadi Nobari
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan, Iran - .,Sports, Scientist, Sepahan Football Club, Isfahan, Iran - .,HEME Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain -
| | - Amir Barjaste
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Guilan, Rasht, Iran
| | - Hamed Haghighi
- Department of Sport Injuries and Corrective Exercises, Faculty of Sport Sciences, University of Isfahan, Isfahan, Iran
| | - Filipe M Clemente
- Escola Superior Desporto e Lazer, Instituto Politécnico de Viana do Castelo, Rua Escola Industrial e Comercial de Nun'Álvares, Viana do Castelo, Portugal
| | - Jorge Carlos-Vivas
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain
| | - Jorge Perez-Gomez
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain
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Nobari H, Kargarfard M, Minasian V, Cholewa JM, Pérez-Gómez J. The effects of 14-week betaine supplementation on endocrine markers, body composition and anthropometrics in professional youth soccer players: a double blind, randomized, placebo-controlled trial. J Int Soc Sports Nutr 2021; 18:20. [PMID: 33663545 PMCID: PMC7934563 DOI: 10.1186/s12970-021-00417-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 02/23/2021] [Indexed: 12/14/2022] Open
Abstract
Objective Betaine supplementation may enhance body composition outcomes when supplemented chronically during an exercise program. The purpose of this study was to evaluate the effect of betaine supplementation on development-related hormones, body composition, and anthropometrics in professional youth soccer players during a competitive season. Methods Twenty-nine players (age, 15.45 ± 0.25 years) were matched based upon position and then randomly assigned to a betaine group (2 g/day; n = 14, BG) or placebo group (PG, n = 15). All subjects participated in team practices, conditioning, and games. If a subject did not participate in a game, a conditioning protocol was used to ensure workload was standardized throughout the 14-week season. Growth hormone (GH), insulin-like growth factor-1 (IGF-1), testosterone, cortisol, height, weight, and body composition were assessed at pre-season (P1), mid-season (P2) and post-season (P3). Anthropometric variables were also measured following a one-year follow-up (F). Results Significant (p < 0.05) group x time interactions were found for testosterone and testosterone to cortisol ratio (T/C). Both variables were greater in BG at P2 and P3 compared to P1, however, the testosterone was less in the PG at P3 compared to P2. There was no significant group by time interactions for GH, IGF-1, lean body mass, or body fat. There was a significant (p < 0.05) group x time interaction in height and weight at F, with the greater increases in BG compared to PG. Conclusion Betaine supplementation increased testosterone levels and T/C ratio in youth professional soccer players during a competitive season. Betaine supplementation had no negative effects on growth (height and weight) and may attenuate reductions in testosterone due to intense training during puberty. Supplementary Information The online version contains supplementary material available at 10.1186/s12970-021-00417-5.
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Affiliation(s)
- Hadi Nobari
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan, Iran
| | - Mehdi Kargarfard
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan, Iran.
| | - Vazgen Minasian
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan, Iran
| | - Jason M Cholewa
- Department of Exercise Physiology, College of Health Sciences, University of Lynchburg, Lynchburg, VA, 24501, USA.
| | - Jorge Pérez-Gómez
- HEME Research Group, Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain
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