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1.
Eur J Appl Physiol ; 124(5): 1461-1474, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38112794

RESUMO

PURPOSE: To evaluate non-specific and ski-specific performance development in male (M) and female (F) peri-pubertal cross-country skiers and to evaluate their relationship with cross-country skiing (XCS) performance and biological maturation within each age category and sex. METHODS: Twenty-one and 19 athletes under 14 and 16 years old, respectively (U14 and U16), were tested for biological maturation; non-specific speed, agility, strength, endurance, and balance; ski-specific speed, agility, and endurance. XCS index was considered as average percentage time-gap from the winner in four official races. Sex and age-category effects were verified and a model predicting XCS index was extrapolated for each group. RESULTS: Performance capacities raised across age categories (p < 0.05) except for non-specific speed, agility, balance, and relative arm strength (p > 0.05). F showed advanced biological maturation and greater balance than M (p < 0.05), while M showed higher performance capacities (p < 0.05). XCS index was not related to biological maturation within each group (p > 0.05); its variance was explained by non-specific speed and ski-specific upper-body endurance in M-U14 (p = 0.014), lower-limb strength and ski-specific agility in M-U16 and F-U14 (both p = 0.001), ski-specific upper-body endurance in F-U16 (p = 0.002). CONCLUSION: Ski-specific performance capacities still develop during peri-puberty, with peri-pubertal M overperforming with respect to F of comparable performance level. XCS index was not influenced by biological maturation withing each age category, but it was rather explained by specific parameters that commonly undergo the "adolescent spurts", accordingly to the average biological maturation level of M and F athletes of each age category.


Assuntos
Desempenho Atlético , Esqui , Humanos , Esqui/fisiologia , Masculino , Adolescente , Feminino , Desempenho Atlético/fisiologia , Resistência Física/fisiologia , Força Muscular/fisiologia
2.
Scand J Med Sci Sports ; 30(8): 1506-1517, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32335945

RESUMO

To assess the real-life magnitude of the heading incidence in children's and youth' football in eight European countries with different "football cultures," a cross-sectional observational design, in which one match per team in 480 different teams from eight European countries (2017/18-2018/19), was recorded by video. One training session was recorded in 312 teams. Clubs with Under-10, Under-12 (female/male/mixed), and Under-16 female and male teams were eligible to participate. Heading frequencies and types were analyzed. Results are presented as headers per match/training and per team. Incidence rates (IR) per 1000 match/training hours were calculated. Under-10 teams carried out the lowest average number of headers per match (8.8), followed by Under-16 female (17.7), Under-12 (18.4), and Under-16 male (35.5). Total number of headers per match and team varied between countries. 80% of the total number of headers were single intentional headers, 12% heading duels, 3% unintentional headers by getting hit, and 5% others (trends apparent in all age groups). Three head injuries occurred during match play corresponding to an IR of 0.70 (95% CI, 0.23-2.16). The lowest number of headers per training and team was found in Under-10 (21.3), followed by Under-16 females (34.1), Under-12 (35.8), and Under-16 males (45.0). In conclusion, this large-scale study presents novel data about the number and type of headers in youth' football throughout Europe. A more precise understanding of the heading incidence, specifically in young players, is mandatory for the debate of restrictions on heading in youth football.


Assuntos
Cabeça , Futebol/estatística & dados numéricos , Esportes Juvenis/estatística & dados numéricos , Adolescente , Criança , Estudos Transversais , Europa (Continente) , Feminino , Humanos , Incidência , Masculino
3.
J Sports Sci ; 36(8): 901-906, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28671853

RESUMO

In the literature there is a lack of data about the development of top level athletes in cross-country mountain biking (XCO). The purpose of this study was to analyze anthropometric and physiological characteristics of some of the best XCO bikers aged between 13 and 16. The study involved 45 bikers (26 males and 19 females) belonging to a youth national team. The evaluations, consisting of anthropometric measures, incremental cycling tests (VO2max, PPO, P@RCP), and 30 s Wingate Tests (PMax, PMean), were conducted over a lapse of 4 years. Our findings showed in bikers, already at young age, a specific athletic profile advantageous for XCO performance. At the age of 16, just before entering the junior category and competing at international level, male and female bikers showed physiological values normalized to the body mass comparable to those reported in literature for high level athletes (VO2max>70 and >60 ml/kg/min, PPO >6.5 and >5.5 W/kg, respectively in males and females). The production of high power-to-weight ratios and high peaks of anaerobic power attests the presence of highly developed aerobic and anaerobic systems in young XCO cyclists reflecting the high physiological demand of this sport.


Assuntos
Antropometria , Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Adolescente , Aptidão , Estatura , Índice de Massa Corporal , Teste de Esforço , Feminino , Humanos , Masculino , Consumo de Oxigênio/fisiologia
4.
AIMS Public Health ; 11(1): 315-329, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617408

RESUMO

The return-to-play process' characteristics can vary by injury and sport type but are typically composed of phases of different durations, training targets, and intensities that gradually increase the physiological and mechanical load. In team sports, contact drills are a necessary part of the last phases of this process, and they should be planned using the optimal mechanical load. The present study investigated the external load and kinetic recovery in U19 soccer players performing 6vs6 and 3vs3 small-sided games. A global positioning system (GPS) measured external load metrics. The rate of perceived exertion (RPE) was registered at the end. Total quality of recovery (TQR) was collected at the beginning of the training session and after 24 h. Moreover, before and after the small-sided games (SSGs) and at 24 h, delayed-onset muscle soreness (DOMS) of the legs, sprinting time, and vertical jump height (CMJ) were collected. 6vs6 presented higher values in total distance low-, moderate-, high, and very-high-speed distance, and maximum speed (p < 0.05). However, 3vs3 showed higher number of sprints, acceleration, and deceleration at different intensities. Furthermore, no difference was shown in RPE. The effect of fatigue on sprint seems greater for 6vs6, showing an impairment persistent at 24 h (p < 0.05). Moreover, CMJ height was impaired after 6vs6 and at 24 h (p < 0.05) but did not change after 3vs3 (p > 0.05). DOMS values after SSGs and at 24 h were higher than baseline for both conditions (p < 0.05), while TQR decreased at 24 h in both conditions (p < 0.05). Based on our results, it seems that 6vs6, leading to a greater high-speed running distance, might cause a training load that needs more time to recover. This point may be crucial in a return-to-play process, especially when hamstring muscles are involved.

5.
J Sports Sci ; 31(13): 1481-90, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23855725

RESUMO

The aim of the study was to examine the post-exercise effects of the "FIFA 11+" on various physical performance and physiological variables, to understand whether this programme is an appropriate warm-up for football players. Results were compared with the literature using a meta-analytical approach. Twenty amateur male football players [mean age 25.5 (s ± 5.1) years, body mass 75(8) kg, height 181(6) cm] participated in the study. They were tested twice before (control period) and once after the "FIFA 11+" for: 20-m sprints, agility, vertical jump, stiffness, isometric maximal voluntary contraction (MVC), rate of force development (RFD), and star excursion balance test. Oxygen uptake, lactate and core temperature were also measured. Pre-post warm-up differences were found for all the performance variables (from 1.0 to 6.2%; 0.015 < P < 0.001) with the exclusion of MVC (-13%; P = 0.426) and RFD (-10%; P = 0.205). After the warm-up there was an increase (0.004


Assuntos
Traumatismos em Atletas/prevenção & controle , Desempenho Atlético/fisiologia , Futebol/fisiologia , Exercício de Aquecimento/fisiologia , Adulto , Temperatura Corporal , Humanos , Ácido Láctico/sangue , Masculino , Metanálise como Assunto , Movimento , Contração Muscular , Consumo de Oxigênio , Corrida
6.
Eur J Sport Sci ; 23(6): 1047-1055, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35658800

RESUMO

This study aimed to compare the effectiveness of recreational football performed once (LOW) vs. twice (MOD) a week on cardiovascular risk factors in healthy, sedentary men. Body composition, resting blood pressure, blood lipid profile and maximal oxygen consumption (VO2max) were measured at baseline, after a 12-week control and training period, using an interrupted time-series study (study 1, n = 18: n = 8, LOW and n = 10, MOD) nested in a randomized parallel trial (study 2, n = 34: n = 18 LOW and n = 16 MOD). After the intervention in study 1, LDL-cholesterol (-12.3 mg·dL-1 [-22.7 to -2.0]) and VO2max (4.5 ml·kg-1·min-1 [1.2-7.8 ]) changed in LOW whereas differences were found in weight (-2.1 kg [-3.7 to -0.4]), BMI (-0.7 kg·m-2 [-1.2 to -0.1]), total cholesterol (-22.2 mg·dL-1 [-36.0 to -8.4]), no-HDL-cholesterol (-17.5 mg·dL-1 [-30.5 to -4.5]), LDL-cholesterol (-14.9 mg·dL-1 [-23.6 to -6.2]) and VO2max (5.7 ml·kg-1·min-1 [2.8-8.6]) in MOD. Study 2 showed no evidence of differences between groups. Our results therefore suggest positive health effects of recreational football even when performed at low frequency as it can happen in real context.Highlights Moderate and high amount of recreational football practice (i.e. 2 or 3 h a week) have been shown to be effective to improve health-related factors in both healthy and unhealthy people.Scarce data are present regarding the effect of a low frequency of recreational football practice (i.e. 1 h a week) that is often usual in a real context.Our results showed the practice of recreational football, once a week, is effective for improving some cardiovascular risk factors (maximal oxygen consumption and LDL-cholesterol) in sedentary, healthy middle-aged men.Moreover, practising recreational football once or twice a week seems to lead to similar positive health adaptations.


Assuntos
Doenças Cardiovasculares , Futebol Americano , Masculino , Pessoa de Meia-Idade , Humanos , Futebol Americano/fisiologia , Aptidão Física/fisiologia , Doenças Cardiovasculares/prevenção & controle , Fatores de Risco , Consumo de Oxigênio/fisiologia , Colesterol , Fatores de Risco de Doenças Cardíacas
7.
PLoS One ; 18(5): e0283781, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37141307

RESUMO

This study aimed to evaluate youth-to-senior transition and the relative age effect in Italian female football national teams. Birthdate data of 774 female players selected for Under 17 (N = 416), 19 (N = 265) and National Senior team (N = 93) were analysed. The youth-to-senior transition rate was determined by the number of youth players competing in the Senior National team (and vice versa), whilst birth quarter (Q) distributions with a chi-square goodness-of-fit test. Only 17.4% of youth players were able to be selected for the Senior National team, whereas 31.2% of the players reached the high-senior level without being selected for youth age groups. Data revealed a skewed birth date distribution in Under 17 and 19 teams (on average, Q1 = 35.6% vs Q4 = 18.5%) but not in the Senior National team. Youth players born in Q1 were two times more likely to be selected than in Q4. In Under 17, goalkeepers, defenders, and midfielders of Q1 players were overrepresented. However, Q4 players recorded higher conversion rates than Q1 (Q1 = 16.4% vs. Q4 = 25.0%). National youth experience may not be a prerequisite for being selected at the senior level. Moreover, this confers a higher probability of playing in the National Senior team than players not selected in youth rosters.


Assuntos
Futebol Americano , Futebol , Humanos , Feminino , Adolescente , Fatores Etários , Itália
8.
BMJ Open ; 13(12): e072291, 2023 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-38135320

RESUMO

OBJECTIVE: Protein-energy malnutrition and the subsequent muscle wasting (sarcopenia) are common ageing complications. It is knowing to be also associated with dementia. Our programme will test the cytoprotective functions of vitamin E combined with the cortisol-lowering effect of chocolate polyphenols (PP), in combination with muscle anabolic effect of adequate dietary protein intake and physical exercise to prevent the age-dependent decline of muscle mass and its key underpinning mechanisms including mitochondrial function, and nutrient metabolism in muscle in the elderly. METHODS AND ANALYSIS: In 2020, a 6-month double-blind randomised controlled trial in 75 predementia older people was launched to prevent muscle mass loss, in respond to the 'Joint Programming Initiative A healthy diet for a healthy life'. In the run-in phase, participants will be stabilised on a protein-rich diet (0.9-1.0 g protein/kg ideal body weight/day) and physical exercise programme (high-intensity interval training specifically developed for these subjects). Subsequently, they will be randomised into three groups (1:1:1). The study arms will have a similar isocaloric diet and follow a similar physical exercise programme. Control group (n=25) will maintain the baseline diet; intervention groups will consume either 30 g/day of dark chocolate containing 500 mg total PP (corresponding to 60 mg epicatechin) and 100 mg vitamin E (as RRR-alpha-tocopherol) (n=25); or the high polyphenol chocolate without additional vitamin E (n=25). Muscle mass will be the primary endpoint. Other outcomes are neurocognitive status and previously identified biomolecular indices of frailty in predementia patients. Muscle biopsies will be collected to assess myocyte contraction and mitochondrial metabolism. Blood and plasma samples will be analysed for laboratory endpoints including nutrition metabolism and omics. ETHICS AND DISSEMINATION: All the ethical and regulatory approvals have been obtained by the ethical committees of the Azienda Ospedaliera Universitaria Integrata of Verona with respect to scientific content and compliance with applicable research and human subjects' regulation. Given the broader interest of the society toward undernutrition in the elderly, we identify four main target audiences for our research activity: national and local health systems, both internal and external to the project; targeted population (the elderly); general public; and academia. These activities include scientific workshops, public health awareness campaigns, project dedicated website and publication is scientific peer-review journals. TRIAL REGISTRATION NUMBER: NCT05343611.


Assuntos
Chocolate , Desnutrição Proteico-Calórica , Idoso , Humanos , Proteínas Alimentares , Vitamina E/uso terapêutico , Exercício Físico , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Artigo em Inglês | MEDLINE | ID: mdl-36141440

RESUMO

Women's participation in sports has recently grown worldwide, including in sports typically associated with men (e.g., rugby and football). Similarly, literature on female athletes has increased, but how they cope with premenstrual (PM) physical and affective symptoms remains a poorly studied topic. Our study aimed to explain which coping strategies elite female rugby and football players use during their PM period to maintain perceived physical ability (PPA) and well-being. A mediation model analysis considering coping strategies (i.e., avoiding harm, awareness and acceptance, adjusting energy, self-care, and communicating) as independent variables, PPA and well-being as dependent variables, and PM physical and affective symptoms and PM cognitive resources as mediators was run on the data collected via an anonymous online survey. A dysfunctional impact of avoiding harm (indirect) and adjusting energy (both direct and indirect) and a functional indirect influence of awareness and acceptance, self-care, and communicating as coping strategies were found on PPA and well-being during the PM period. As predicted, PM physical and affective symptoms as mediators reduced PPA and well-being, while PM cognitive resources enhanced them. These results may inform practitioners on how to support elite female athletes' PPA and well-being by knowing and reinforcing the most functional PM coping strategies for them.


Assuntos
Futebol Americano , Futebol , Adaptação Psicológica , Atletas/psicologia , Feminino , Futebol Americano/psicologia , Humanos , Masculino , Rugby
10.
J Sports Med Phys Fitness ; 62(10): 1329-1337, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34913625

RESUMO

BACKGROUND: The COVID-19 pandemic requires the adoption of strict preventive measures, such as wearing a protective face mask, but few studies investigated its impact during exercise. We investigated the effects of wearing a protective face mask while exercising at different intensities and verified whether differences between two types of protective face masks exist. METHODS: Twenty subjects performed 4-min running at 8 km•h-1 and at 10 km•h-1, 8 x 90-m Intermittent running bouts and the Yo-Yo Intermittent Recovery Test Level-1, while wearing either a surgical mask, a sports-reusable mask or no mask. Physiological responses (HR, [La], SpO2), overall and breathlessness perceived exertion and YYIRT1-distance were assessed. RESULTS: Breathlessness RPE was greater with surgical than without mask at the end of the run at 8 km•h-1 (+7.18 [3.21, 11.50]) and with both surgical and sports-reusable mask than without mask at the end of the run at 10 km•h-1 (+8.09 [4.09, 12.60] and +8.21 [4.53, 12.70]) and intermittent exercise (+11.10 [6.41, 16.10] and +10.50 [6.18, 15.30]). Overall RPE was greater with surgical than without mask at the end of the run at 8 (+3.71 [1.15, 6.91]) and 10 km•h-1 (+5.29 [2.26, 8.85]). Furthermore, YYIRT1 performance was lower with surgical (-150 m [44, 240]) and sports-reusable mask (-201 m [108, 286]) than without mask. CONCLUSIONS: Regardless of exercise intensity and mask type, wearing a protective face mask mostly affects perceptual responses, also causing a performance reduction during maximal exercise. These findings must be considered when prescribing/practicing exercise while wearing a protective face mask.


Assuntos
COVID-19 , Dispneia , Exercício Físico , Humanos , Máscaras , Pandemias/prevenção & controle
11.
Front Physiol ; 13: 960773, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105278

RESUMO

Mild degrees of hypoxia are known to exert a detrimental effect on cognitive functions. In a lab study, we assessed the effect of mild hypoxia on risk-taking behavior. Participants (N = 25) were presented with pairs of bets of equal expected monetary value, one having a higher probability of winning/losing a lower payoff (safer bet) and one having a lower probability of winning/losing a higher payoff (riskier bet). We systematically varied the ratio of the probabilities (and corresponding payoffs) of the two bets and examined how this affected participants' choice between them. Following a familiarization session, participants performed the task twice: once in a normoxic environment (20.9% oxygen concentration) and once in a mildly hypoxic environment (14.1% oxygen concentration). Participants were not told and could not guess which environment they were in. We found a higher preference for the riskier bet in the mild hypoxic than normoxic environment but only in the loss domain. Furthermore, as the probability ratio increased, mild hypoxia increased the preference for the riskier bet in the domain of losses but decreased it for gains. The present findings support that mild hypoxia promotes riskier choices in the loss domain and provide new insights into the impact of mild hypoxia in moderating the effect of probability ratio on risky choices.

12.
Front Physiol ; 12: 737249, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744777

RESUMO

Ski mountaineering is a rapidly growing winter sport that involves alternately climbing and descending slopes and various racing formats that differ in length and total vertical gain, as well as their distribution of downhill and uphill sections. In recent years, both participation in and media coverage of this sport have increased dramatically, contributing, at least in part, to its inclusion in the 2026 Winter Olympics in Milano-Cortina. Here, our aim has been to briefly describe the major characteristics of ski mountaineering, its physiological and biomechanical demands, equipment, and training/testing, as well as to provide some future perspectives. Despite its popularity, research on this discipline is scarce, but some general characteristics are already emerging. Pronounced aerobic capacity is an important requirement for success, as demonstrated by positive correlations between racing time and maximal oxygen uptake and oxygen uptake at the second ventilatory threshold. Moreover, due to the considerable mechanical work against gravity on demanding uphill terrain, the combined weight of the athlete and equipment is inversely correlated with performance, prompting the development of both lighter and better equipment in recent decades. In ski mountaineering, velocity uphill is achieved primarily by more frequent (rather than longer) strides due primarily to high resistive forces. The use of wearable technologies, designed specifically for analysis in the field (including at elevated altitudes and cold temperatures) and more extensive collaboration between researchers, industrial actors, and coaches/athletes, could further improve the development of this sport.

13.
Artigo em Inglês | MEDLINE | ID: mdl-33345100

RESUMO

Introduction: Very little is known about talent development and selection processes in young cross-country skiers. Aim: (1) to analyze the effect of age on anthropometric and physiological parameters in medium-to-high level cross-country skiers during the late teenage period; (2) to describe parameters' trend in selected talents after the late teenage period; (3) to define which characteristics during the late teenage period could discriminate against further talent selection. Method: We found 14 male (M) and nine (F) athletes in our database, identified as talents by regional teams during the late teenage period, who performed the same diagonal-stride roller-skiing incremental test to exhaustion at 17 and 18 years old. Of these, four M and three F teenagers performed four further evaluations, and were selected by the national team. Age effect during the late teenage period was verified on anthropometric and physiological parameters measured at maximal intensity (MAX), first (VT1), and second (VT2) ventilatory thresholds, and 3° and 6° of treadmill incline. An observational analysis allowed to evaluate parameters' trend after the late teenage period in selected athletes, and to determine possible characteristics early discriminating further selection. Results: During the late teenage period, height, weight, and BMI was still raising in M as well as V'O2 at VT2 and 6° of treadmill incline (all P > 0.05). In F, mass-scaled V'O2 MAX increased while heart rate (HR) at MAX and VT2 decreased (all P > 0.05). Since the late teenage period, all selected males showed maximal ventilation volumes, absolute V'O2 at MAX, VT1, and VT2 that were within or above the 75th percentile of their group; the same was found in selected females for mass-scaled V'O2 MAX, VT1, and VT2 time. After the late teenage period, all selected athletes showed an increasing trend for VT2 time, while a decreasing trend for sub-maximal energetic cost, %V'O2 and HR. Discussion: During the late teenage period, males are still completing their maturation process. Since the late teenage period, some physiological parameters seem good indicators to early discriminate for further talents. A progressive increase in skiing efficiency was demonstrated in developing talents of both sexes after the late teenage period.

14.
Int J Sports Physiol Perform ; 11(3): 388-92, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26309332

RESUMO

PURPOSE: To examine the construct validity of the session rating perceived exertion (s-RPE) assessed with the Borg CR100 scale to measure training loads in elite soccer and to examine if the CR100 is interchangeable and can provide more-accurate ratings than the CR10 scale. METHODS: Two studies were conducted. The validity of the CR100 was determined in 19 elite soccer players (age 28 ± 6 y, height 180 ± 7 cm, body mass 77 ± 6 kg) during training sessions through correlations with the Edwards heart-rate method (study 1). The interchangeability with CR10 was assessed in 78 soccer players (age 19.3 ± 4.1 y, height 178 ± 5.9 cm, body mass 71.4 ± 6.1 kg) through the Bland-Altman method and correlations between change scores in different sessions. To examine whether the CR100 is more finely graded than the CR10, the proportions of responses corresponding to the verbal expressions were calculated (study 2). RESULTS: Individual correlations between the Edwards method and s-RPE were large to very large (.52-.85). The mean difference between the 2 scales was -0.3 ± 0.33 AU (90% CI -0.41 to -0.29) with 95% limits of agreements (0.31 to -0.96 AU). Correlations between scales and between-changes scores were nearly perfect (.95 and .91-.98). Ratings corresponding to the verbal anchors were 49% in CR10 and 26% in CR100. CONCLUSIONS: The CR100 is valid for assessing the training load in elite soccer players. It can be used interchangeably with the CR10 and may provide more-precise measures of exercise intensity.


Assuntos
Teste de Esforço/métodos , Esforço Físico , Futebol/fisiologia , Adolescente , Adulto , Atletas , Frequência Cardíaca , Humanos , Condicionamento Físico Humano , Adulto Jovem
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