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1.
J Sports Med Phys Fitness ; 63(11): 1175-1181, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37535340

RESUMO

INTRODUCTION: Wheelchair fencing (WF) is a very practiced sport within the Paralympic world. A careful analysis of the characteristics and data of a WF athlete can be useful for coaches and movement experts to better plan a training program. The objective of the study was to evaluate physical fitness assessment methods adopted in WF and to propose a standard operating procedures (SOP). EVIDENCE ACQUISITION: Original articles written in English were included in this review, and the population studied was composed of athletes who practiced WF. Studies were searched from PubMed, Web of Science, and Scopus databases using keywords and Boolean operators. Eight studies were included in this review. EVIDENCE SYNTHESIS: Most of the studies converge and agree on the physical, physiological, and technical characteristics of a WF athlete. CONCLUSIONS: The scientific literature referring to this sport is very scarce, hence the need for new original studies to optimize the SOP proposed.


Assuntos
Esportes , Cadeiras de Rodas , Humanos , Esportes/fisiologia , Atletas , Exercício Físico , Desempenho Físico Funcional
2.
J Sports Med Phys Fitness ; 61(12): 1578-1586, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33615760

RESUMO

BACKGROUND: This study investigated the possible influence of the gender on the responses of swimmers during a taper period (TP). METHODS: Ten males (19±3 years and 73.5±7.8 kg) and ten females (17±2 years and 54.7±7.2 kg) swimmers were submitted to a 12-week training, followed by three weeks of the TP. Before and after the TP we evaluated the performance at 100 m freestyle, stroke parameters and lactacidemic responses; lactate minimum intensity (LMI) and stroke parameters associated with LMI and the propulsive force in tethered swimming. TP consisted of 14 sessions with mean volume 2253±1213 m/session at an intensity below than the LMI, 1730±327 m/session at an intensity near the LMI and 1530±1019 m/session at an intensity above the LMI. RESULTS: Significant effects of the genders were observed for LMI and stroke parameters (P<0.001 and η2>0.52 [large]) and propulsive force (P=0.001; η2=0.59 [large]). However, no significant effects of the TP were identified in the performance of the 100 m freestyle (P=0.66; η2=0.006 [small]), propulsive force (P>0.63; η2<0.006 [small]), aerobic parameters (LMI: P=0.32 and η2=0.03 [small]) and mechanical parameters (P>0.23; η2=0.01 [small]). Nonetheless, the peak blood lactate concentrations were improved after TP (P=0.014; η2=0.16 [large]), without significant interactions (P=0.38; η2=0.02 [small]), as well as the mechanical parameters during maximum 100 m freestyle (P<0.04 and η2>0.10 [medium]). CONCLUSIONS: Hence, men and women presenting significantly different values in the age group studied, the responses observed after the TP investigated were the same independent of gender.


Assuntos
Desempenho Atlético , Condicionamento Físico Humano , Natação , Adolescente , Atletas , Feminino , Humanos , Ácido Láctico , Masculino , Adulto Jovem
3.
J Sports Med Phys Fitness ; 61(4): 519-526, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33092326

RESUMO

BACKGROUND: Backward extrapolation technique (BE) was used to estimate V̇O2 from postexercise measuring, eliminating oronasal mask (OM) during the efforts. Despite its advantage, literature presents discrepancy in applied methods. Thus, the first aim of this study was to compare different mathematical criteria to estimate values of V̇O2 during a supramaximal effort (V̇O2PEAK), while the second aim was to verify the effects of OM on cycling performance. METHODS: Twenty-four male cyclists (35±6 years, 81.3±8.9 kg, 180±6 cm) performed three days of tests, with at least 24 h of interval between each test. Firstly, a graded exercise test was applied to determine V̇O2max and your correspondent intensity (MAP). The second and the third day were destined to supramaximal efforts at 120% of MAP, performed with (Supramask) and without (Suprabe) oronasal mask (OM) in a randomized order. After Suprabe, OM was coupled, and BE was applied. Sixty-six values of V̇O2 were obtained based on a linear regression fitting. RESULTS: V̇O2peak can be estimated using different curve lengths. However, only curves between 20 and 60 s with extrapolation to 3 s or lesser shows at least one consistent criterion. The 60 s curve extrapoled to -3 s was the most accurate criteria (P=0.723; ES=-0.055; r=0.824; Bias=-0.36 and LoA=7.72 mL.kg.min-1). Performance was not impaired with OM and was similar in both condition (P=0.84, ES=0.04). CONCLUSIONS: We conclude that it was possible to accurately estimate V̇O2 values of a supramaximal effort without any respiratory apparatus with a time-efficient analysis. Therefore, we recommended the use of a 60 seconds V̇O2 curve analysis with a negative extrapolation for 3 seconds.


Assuntos
Ciclismo/fisiologia , Consumo de Oxigênio/fisiologia , Adulto , Exercício Físico , Teste de Esforço/métodos , Humanos , Masculino
4.
Front Physiol ; 10: 643, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31231234

RESUMO

Ankle muscle fatigue has been shown to increase body sway. In addition, body sway in quiet upright standing is reduced when saccadic eye movements are performed. The purpose of this study was to investigate the effects of visual information manipulation on postural control during ankle muscle fatigue in young adults. Twenty young adults performed: (1) two 60-s trials in quiet bipedal standing with eyes open, eyes closed, and while performing saccadic eye movements; (2) maximum voluntary isometric contractions in a leg press device, custom-made to test ankle plantar flexion force; (3) a calf raise exercise on top of a step to induce ankle muscle fatigue; and (4) a repetition of items 1 and 2. Postural sway parameters were compared with two-way ANOVAs (vision condition × fatigue; p < 0.05). Ankle muscle fatigue increased anterior-posterior and medial-lateral displacement and RMS of sway, as well as sway area. Saccadic eye movements reduced anterior-posterior displacement and RMS of sway and area of sway compared to eyes open and eyes closed conditions. Both saccadic eye movements and eyes closed increased the frequency of AP sway compared to the eyes open condition. Finally, anterior-posterior displacement, anterior-posterior RMS, and both anterior-posterior and medial-lateral sway frequency were affected by an interaction of fatigue and vision condition. Without muscle fatigue, closing the eyes increased anterior-posterior displacement and RMS of sway, compared to eyes open, while during muscle fatigue closing the eyes closed reduced anterior-posterior displacement and had no significant effect on anterior-posterior RMS. In conclusion, body sway was increased after induction of ankle muscle fatigue. Saccadic eye movements consistently reduced postural sway in fatigued and unfatigued conditions. Surprisingly, closing the eyes increased sway in the unfatigued condition but reduced sway in the fatigued condition.

5.
J Sports Med Phys Fitness ; 59(11): 1852-1860, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31062949

RESUMO

BACKGROUND: Task constraints and players' asymmetry influences on lower extremity (i.e. kicking limb) kinematics during futsal instep kicking. However, support limb behavior when shooting in a futsal context was not previously investigated, and its potential role on such discrepant motor outputs is still unclear. Thus, the study aimed to compare kinematic features of the support limb and approach run between kicking a stationary and a rolling ball using dominant and non-dominant limbs. METHODS: Ten futsal players participated (21.88±2.86 years-old, 73.66±4.17 kg and 1.75±0.04 m) and performed kicks (five per limb per condition) with the dominant and non-dominant limbs in stationary and rolling ball conditions. Kinematic analysis comprised determination of support limb angular joint (hip, knee and ankle) displacement and velocity, approach run distance, angle, linear velocity, step length and width, support foot-to-ball distance, ball velocity (120 Hz) and accuracy (60 Hz). RESULTS: Hip adjustments (greater extension) in the support limb when kicking a rolling ball contributed in maintaining similar performance (e.g., ball velocity) to kicking a stationary ball, compensating for the lower approach run velocity and longer support foot to ball distance. Kicking with the non-dominant limb demonstrated a lower approach run velocity and the non-dominant support limb presented different angular motion compared to the dominant support limb in hip (< internal rotation), knee (< flexion), and ankle joints (< plantar flexion), being harmful to performance in both kicking stationary and rolling balls. CONCLUSIONS: Kicking a stationary and rolling ball presented similar performance, but compared to the dominant side, futsal instep kicks performed with the non-dominant support limb induces lower approach run velocity and inefficient angular joint motion, either harmful to performance output.


Assuntos
Extremidade Inferior/fisiologia , Esportes/fisiologia , Adulto , Tornozelo/fisiologia , Atletas , Desempenho Atlético , Fenômenos Biomecânicos , Quadril/fisiologia , Humanos , Joelho/fisiologia , Masculino , Amplitude de Movimento Articular , Rotação , Adulto Jovem
6.
Front Physiol ; 9: 887, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30050459

RESUMO

Purpose: Training methods based on small-sided game (SSG) seem to promote physiological and tactical benefits for soccer players as they present characteristics more specific to the game. Thus, the main objective of the present study was to analyze the hormonal, biochemical, and autonomic parameters in an acute manner and the recovery dynamics (up to 72 h after) in a SSG. Methods: Thirteen professional female soccer players participated in the study (18.8 ± 0.8 years, body mass 59.4 ± 6.2 kg, and height 1.68 ± 0.05 m). During and after the SSG session (4 min × 4 min separated by 3 min of passive interval and 120 m2 coverage per player), autonomic modulation was analyzed in the time and frequency domains using heart rate variability, and blood samples (5 ml) were collected before (0 h) and after (10 min and 24, 48, 72 h) the SSG for biochemical and hormonal analysis. Results: The SSG induced an increase effect for LF (low frequency) (92,52%; Very likely increase) and a decrease effect for HF (high frequency) values (-65,72%; Very likely decrease), after 10 min of recovery. The LF/HF increase after 10 min of recovery (386,21%; Very likely increase). The RMSSD (square root of the mean squared differences of the successive N-N intervals) and pNN50 (measure of the number of adjacent NN intervals which differ by more than 50 ms) values presented a decrease effect 10 min after SSG (61,38%; Very likely decrease and-90%; Very likely decrease). The CK (creatine kinase) values presented no changes 10 min after SSG. The LDH (lactate dehydrogenase) values presented an increase effect 10 min after the SSG (19,22%; Likely increase). Both testosterone and cortisol concentrations presented the same behavior after SSG, where no alterations were observed with after 10 min (<0,37%; Most likely trivial). Conclusion: The SSG promoted significant cardiovascular stress that was restored within the first 24 h of recovery. Parasympathetic parameters continued to increase while sympathetic parameters declined significantly during the 72 h of recovery. In addition, the reduced game did not alter biochemical or hormonal responses during the 72 h.

7.
Amino Acids ; 50(1): 189-198, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29082444

RESUMO

Taurine can affect the energy system metabolism, specifically the lipid metabolism, since an increase in lipid oxidation may promote carbohydrate savings. We hypothesized that taurine supplementation associated with high-intensity exercise could increase levels of lipolysis, benefiting swimmer performance. Nine male competitive swimmers performed two 400-m front crawl maximal efforts with a 1-week washout, and the athletes received 6 g of taurine (TAU) or placebo (PLA) supplementation 120 min before performing the effort. Oxygen consumption and the contribution of the energy systems were analyzed post effort using a Quark CPET gas analyzer. Blood samples were collected before, and 5 min post the effort for taurine and glycerol analysis. Immediately before and 3, 5, and 7 min post the effort, blood samples from the earlobe were collected to determine lactate levels. An increase of 159% was observed in taurine plasma levels 120 min post ingestion. Glycerol levels were higher in both groups post effort; however, the TAU condition promoted an 8% higher increase than the PLA. No changes were observed in swimmer performance or lactate levels; however, the percentage change in lactate levels (∆[La-]) was different (TAU: 9.36 ± 2.78 mmol L-1; PLA: 11.52 ± 2.19 mmol L-1, p = 0.04). Acute taurine supplementation 120 min before performing a maximal effort did not improve swimmer performance; however, it increased glycerol plasma levels and reduced both the ∆[La-] and lactic anaerobic system contribution.


Assuntos
Suplementos Nutricionais , Metabolismo Energético/efeitos dos fármacos , Lipólise/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Taurina/farmacologia , Adolescente , Atletas , Exercício Físico , Glicerol/sangue , Humanos , Ácido Láctico/sangue , Masculino , Taurina/sangue , Taurina/metabolismo , Adulto Jovem
8.
Front Physiol ; 8: 755, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29066977

RESUMO

Total anaerobic contribution (TAn) can be assessed by accumulated oxygen deficit, and through sum of glycolytic and phosphagen contribution which enable the evaluation of TAn without influences on mechanical parameters. However, little is known about the difference of TAn within swimming distances. Therefore, the objectives of the present study were to determine and compare the TAn in different performances using the backward extrapolation technique and amount of lactate accumulated during exercise, and relate it with swimming performance. Fourteen competitive swimmers performed five maximal front crawl swims of 50, 100, 200, 400, and 800 m. The total phosphagen (AnAl) and glycolytic (AnLa) contributions were assumed as the fast component of post-exercise oxygen consumption (EPOCFAST) and amount of blood lactate accumulated during exercise, respectively. TAn was the sum of AnAl and AnLa. Significantly lower values of AnLa were observed in the 800 m (p < 0.01) than other distances. For AnAl, the 50 m performance presented the lowest values, followed by 100 and 800 m (p < 0.01). The highest values of AnAl were observed in the 200 and 400 m (p > 0.13). The TAn was significantly higher in the 200 and 400 m performances than observed at 50 and 800 m (p < 0.01). Anaerobic contributions were correlated with 50, 100, 200, and 400 m performances (p < 0.01). The AnAl contribution was not correlated with 400 m performance. Anaerobic parameters were not correlated with 800 m performance. In conclusion, the highest values of anaerobic contribution were observed in the 200 and 400 m distances. Moreover, TAn is important to performances below 400 m, and may be used in training routines.

9.
Front Physiol ; 7: 518, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27872598

RESUMO

Purpose: The aim of the present study was to investigate the influence of futsal match-related fatigue on running performance, neuromuscular variables, and finishing kick speed and accuracy. Methods: Ten professional futsal players participated in the study (age: 22.2 ± 2.5 years) and initially performed an incremental protocol to determine maximum oxygen uptake ([Formula: see text]: 50.6 ± 4.9 mL.kg-1.min-1). Next, simulated games were performed, in four periods of 10 min during which heart rate and blood lactate concentration were monitored. The entire games were video recorded for subsequent automatic tracking. Before and immediately after the simulated game, neuromuscular function was measured by maximal isometric force of knee extension, voluntary activation using twitch interpolation technique, and electromyographic activity. Before, at half time, and immediately after the simulated game, the athletes also performed a set of finishing kicks for ball speed and accuracy measurements. Results: Total distance covered (1st half: 1986.6 ± 74.4 m; 2nd half: 1856.0 ± 129.7 m, P = 0.00) and distance covered per minute (1st half: 103.2 ± 4.4 m.min-1; 2nd half: 96.4 ± 7.5 m.min-1, P = 0.00) demonstrated significant declines during the simulated game, as well as maximal isometric force of knee extension (Before: 840.2 ± 66.2 N; After: 751.6 ± 114.3 N, P = 0.04) and voluntary activation (Before: 85.9 ± 7.5%; After: 74.1 ± 12.3%, P = 0.04), however ball speed and accuracy during the finishing kicks were not significantly affected. Conclusion: Therefore, we conclude that despite the decline in running performance and neuromuscular variables presenting an important manifestation of central fatigue, this condition apparently does not affect the speed and accuracy of finishing kicks.

10.
Diabetol Metab Syndr ; 2: 43, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-20573247

RESUMO

BACKGROUND: Fructose-based diets are apparently related to the occurrence of several metabolic dysfunctions, but the effects of the consumption of high amounts of fructose on body tissues have not been well described. The aim of this study was to analyze the general characteristics and the lipid content of different tissues of rats after chronic ingestion of a fructose rich soft drink. METHODS: Forty-five Wistar rats were used. The rats were divided into three groups (n = 15) and allowed to consume water (C), light Coca Cola (R) (L) or regular Coca Cola(R) (R) as the sole source of liquids for eight weeks. RESULTS: The R group presented significantly higher daily liquid intake and significantly lower food intake than the C and L groups. Moreover, relative to the C and L groups, the R group showed higher triglyceride concentrations in the serum and liver. However, the L group animals presented lower values of serum triglycerides and cholesterol than controls. CONCLUSIONS: Based on the results, it can be concluded that daily ingestion of a large amount of fructose- rich soft drink resulted in unfavorable alterations to the lipid profile of the rats.

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