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1.
J Sports Sci ; : 1-9, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984767

RESUMO

The aim of the present study was to investigate the effect of weighted vest on-field small-sided games (SSG) soccer training, during the in-season period, on body composition and soccer-specific performances, in young, trained soccer players. A counterbalance study design was adopted, in which the fourteen well-trained players (age: 19.1 ± 0.5 yrs, body mass: 70.3 ± 5.3 kg, body height: 180.3 ± 3.0 cm, body fat: 9.2 ± 4.1%) performed both the Interventional (Vest) and Control (Con) training routines (6 weeks/season; 5 training sessions/week; 1 match/week), in different occasions (winter/spring period). Con group followed a regular weekly training plan. When the Con group performed their intense training sessions, Vest group performed only the on-field SSGs training wearing a vest (12.5% of athletes' body mass). All the evaluations were performed one week before and after each training period. Statistical analyses include repeated ANOVA and T-test (p < 0.05). Significant increases in sprinting, jumping, change of direction (COD), aerobic and anaerobic performances were observed only after Vest intervention (-4.7 ± 2.2% to 11.2 ± 4.2%; p < 0.05). Significant changes were observed only after Vest training, compared to Cont (p < 0.05). These results suggest that using a weighted vest, during the in-season, onfield SSG training two times/week induces greater increases in young soccer players' sprinting, jumping, COD, aerobic and anaerobic performances.

2.
Nutrients ; 16(13)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38999735

RESUMO

This study aimed to investigate the ability of highly trained athletes to consistently perform at their highest level during a simulated three-day 400 m race and to examine the impact of an alkaline diet associated with chronic consumption of bicarbonate-rich water or placebo on their blood metabolic responses before and after the three races. Twenty-two highly trained athletes, divided into two groups-one with an alkalizing diet and placebo water (PLA) and the other with an alkalizing diet and bicarbonate-rich water (BIC)-performed a 400 m race for three consecutive days. Performance metrics, urine and blood samples assessing acid-base balance, and indirect markers of neuro-muscular fatigue were measured before and after each 400 m race. The evolution of the Potential Renal Acid Load (PRAL) index and urinary pH highlights the combination of an alkalizing diet and bicarbonate-rich hydration, modifying the acid-base state (p < 0.05). Athletes in the PLA group replicated the same level of performance during three consecutive daily races without an increase in fatigue-associated markers. Athletes experienced similar levels of metabolic perturbations during the three 400 m races, with improved lactate clearance 20 min after the third race compared to the first two (p < 0.05). This optimization of the buffering capacity through ecological alkaline nutrition and hydration allowed athletes in the BIC group to improve their performance during the third 400 m race (p < 0.01). This study highlights athletes' ability to replicate high-level performances over three consecutive days with the same extreme level of metabolic disturbances, and an alkaline diet combined with bicarbonate-rich water consumption appears to enhance performance in a 400 m race.


Assuntos
Equilíbrio Ácido-Base , Desempenho Atlético , Bicarbonatos , Humanos , Desempenho Atlético/fisiologia , Masculino , Adulto , Bicarbonatos/sangue , Atletas , Adulto Jovem , Concentração de Íons de Hidrogênio , Dieta/métodos , Ácido Láctico/sangue , Feminino , Fadiga Muscular/fisiologia , Corrida/fisiologia , Resistência Física/fisiologia , Biomarcadores/sangue , Biomarcadores/urina
3.
J Funct Morphol Kinesiol ; 9(2)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38804451

RESUMO

This randomized, double-blinded, experimental study investigated the effects of a four-week daily pre-workout supplementation (200 mg caffeine, 3.3 g creatine monohydrate, 3.2 g ß-alanine, 6 g citrulline malate, and 5 g BCAA) vs. placebo (isocaloric maltodextrin) on anaerobic (jumping, sprinting, agility, and the running-based anaerobic sprint test: RAST) and aerobic (Yo-Yo intermittent recovery test level 1) performance, as well as on body composition and selective muscle damage/health-related blood markers in well-trained basketball players during the in-season period. Eighteen basketball players (age: 24.4 ± 6.3 years, height: 185.7 ± 8.0 cm, weight: 85.7 ± 12.8 kg, body fat: 16.5 ± 4.2%) were randomly assigned into two groups: pre-workout supplement (PWS, n = 10) or placebo (PL, n = 8). PWS consumption increased aerobic performance (PWS: 8 ± 6%; PL: -2 ± 6%; p = 0.004) compared to PL. A significant decrease was observed in peak (F = 7.0; p = 0.017), average (F = 10.7; p = 0.005), and minimum power (F = 5.1; p = 0.039) following 4 weeks of supplementation in both groups. No other significant changes were observed between groups (p > 0.05). In conclusion, the consumption of the current PWS over a four-week period appears to positively influence the aerobic performance of well-trained basketball players during the in-season period. However, it does not appear to mitigate the observed decline in anaerobic power, nor does it affect performance in jumping, sprinting, and agility, or alter body composition or selective muscle damage/health-related blood markers.

4.
J Exerc Sci Fit ; 22(2): 140-144, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38404749

RESUMO

Purpose: The performance of sodium citrate has been investigated in high-intensity exercises, but fewer studies have addressed the role of citrate in weight-bearing exercises. Methods: Twenty fitness challenge athletes, aged 24-32 years, volunteered to participate in this crossover, placebo-controlled, double-blind study. Initially, ten athletes were given a placebo and asked to complete a fitness challenge (i.e., chin-ups, squat jumps, dips, walking lunges, sit-ups, and burpees-devil press). Another ten athletes were supplemented with sodium citrate 0.5 g/kg body mass supplements 3 h prior to performing the fitness challenges. The same procedures were completed two days later with the supplement and placebo dextrose groups switched in a cross-over design. Athletes and assessors were blinded for the experimental condition (placebo vs. verum). Lactate levels were measured 5 min after exercise. The athletes' performance on each item of the fitness challenge as well as their lactate levels, were compared. Differences between the means of the measured variables were contrasted using a dependent t-test. Results: Supplementing sodium citrate substantially improved athletes' performance in all six fitness challenge items (p < 0.05, 0.69

5.
Appl Physiol Nutr Metab ; 49(4): 437-446, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38084583

RESUMO

Changes in physiological markers and physical performance in relation to paratroopers' initial body composition were investigated during a 20-day winter military field training (MFT) and the subsequent 10-day recovery period. Body composition, serum hormone concentrations and enzymatic biomarkers, and physical performance of 58 soldiers were measured before, during, and after MFT. Comparisons were done according to soldiers' body fat percentage before MFT between low-fat (<12% body fat) and high-fat (>12% body fat) groups. Correlations between body fat percentage preceding MFT and changes in muscle mass, physical performance, and serum hormone concentrations and enzymatic biomarkers were investigated. It was hypothesized that soldiers with a higher fat percentage would have smaller decrements in muscle mass, physical performance, and serum testosterone concentration. The change in muscle and fat mass was different between groups (p < 0.001) as the low-fat group lost 0.8 kg of muscle mass and 2.0 kg of fat mass, while there was no change in muscle mass and a loss of 3.7 kg of fat mass in the high-fat group during MFT. Fat percentage before MFT correlated with the changes in muscle mass (R2 = 0.26, p < 0.001), serum testosterone concentration (R2 = 0.22, p < 0.001), and evacuation test time (R2 = 0.10, p < 0.05) during MFT. The change in muscle mass was correlated with the changes in evacuation test time (R2 = 0.11, p < 0.05) and countermovement jump test results (R2 = 0.13, p < 0.01) during MFT. Soldiers with a higher initial fat percentage lost less muscle mass, and had smaller decrements in some aspects of physical performance, as well as in serum testosterone concentration during MFT.


Assuntos
Militares , Força Muscular , Masculino , Humanos , Força Muscular/fisiologia , Desempenho Físico Funcional , Composição Corporal/fisiologia , Biomarcadores , Testosterona
6.
J Sports Sci ; 41(18): 1667-1677, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38060374

RESUMO

The lean body mass (LBM) components have been suggested as important predictors of anaerobic performance, which is highly involved in basketball. We explored with descriptive cross-sectional design the relationship between anaerobic performance and full molecular and cellular body composition profile in young male basketball players. Twenty-one players (age = 16.8 ± 1.6 years; body mass = 76.3 ± 15.7 kg, height = 189.3 ± 12.6 cm) were recruited, 11 elite and 10 local level. Participants were evaluated on multicomponent body composition [LBM, appendicular lean soft tissue (ALST), bone mineral content (BMC), total body water (TBW), intracellular water (ICW) and extracellular water (ECW)] and field-based anaerobic performance (vertical jump, linear sprint, and handgrip strength). The stepwise regression analyses adjusted for confounders showed significant relationships of whole-body and regional body composition components with handgrip and jump performance (P ≤ 0.03). Prediction models combining body composition variables assessed by bioimpedance analysis (BIA) and double-energy X-ray absorptiometry (DXA) revealed that lean mass and hydration ratios (ICW/ECW and ECW/TBW) were strongly associated with jump performance (CMJ and CMJ25kg), independently of the competition level (P < 0.01). The novel finding in this study was that water quality (ICW/ECW) and water distribution (ECW/TBW, ICW) of total and regional LBM were the main predictors of vertical jump capacity in young basketball players.


Assuntos
Basquetebol , Humanos , Masculino , Adolescente , Água Corporal , Força da Mão , Estudos Transversais , Composição Corporal , Impedância Elétrica
7.
Res Sports Med ; : 1-17, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38126743

RESUMO

Ischaemic preconditioning (IPC), brief periods of ischaemia immediately followed by reperfusion applied to a vascular bed, has emerged as a method to improve exercise performance. There is, however, a lack of research exploring repeated episodes of IPC on anaerobic performance. The aim of this study was to determine if a 2-week repeated IPC intervention could enhance anaerobic performance in male academy football players. Eight male academy football players completed two, 2-week intervention trials: six IPC episodes (4 × 5 min at 220 mmHg per episode), and six SHAM episodes (4 × 5 min at 20 mmHg per episode). Prior to and following each intervention trial, the participants completed assessments of anaerobic performance (Running Anaerobic Sprint Test [RAST]), and superficial femoral artery endothelial function (flow-mediated dilation [FMD]). IPC significantly enhanced peak and mean power output by 12% (p = 0.026) and 11% (p = 0.019) and significantly improved superficial femoral artery FMD (p = 0.049). The increase in endothelial function suggests that this may be a mechanism contributing to this enhancement of anaerobic performance. The present study supports the use of repeated IPC prior to matches and training sessions to enhance anaerobic performance.

9.
Medicina (Kaunas) ; 59(11)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38004044

RESUMO

Background and Objectives: This study was conducted to examine the influence of different swimming and running protocols as forms of physiological preconditioning on an isolated rat heart's ischemia/reperfusion injury. Materials and Methods: This study was conducted on 60 male Wistar albino rats (6 weeks old, bw: 200 ± 20 g), divided into: CTRL group-a sedentary control group; sAeT-a group that underwent aerobic swimming conditioning using a swimming protocol for 8 weeks; sAnT-a group that underwent anaerobic swimming conditioning; rAeT-a group that underwent aerobic running conditioning; and rAnT-a group that underwent anaerobic running conditioning. After the preconditioning protocols, ex vivo estimating of myocardial function according to the Langendorff technique was performed. Results: The anaerobic running training decreased heart rate and the anaerobic swimming training reduced coronary flow, demonstrating the difference in the physiological heart response of aerobic/anaerobic physical training (p < 0.05). Heart rate was significantly reduced in both training swimming groups after a period of ischemia (p < 0.05). On the other hand, the anaerobic running protocol induced a significantly decreased heart rate in comparison with the aerobic running group and the sedentary group (p < 0.05). Conclusions: The data from this experimental study support many protective training effects, i.e., improved contractility, improved resting heart rate, and increased physical work capacity and exercise tolerance. Physical training in the form of anaerobic running induces greater heart preconditioning for reperfusion injury in comparison with anaerobic swimming training.


Assuntos
Traumatismo por Reperfusão Miocárdica , Corrida , Ratos , Masculino , Animais , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Ratos Wistar , Natação/fisiologia , Isquemia , Modelos Teóricos
10.
J Neuroeng Rehabil ; 20(1): 97, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37496055

RESUMO

BACKGROUND: Despite reporting the positive effects of transcranial direct current stimulation (tDCS) on endurance performance, very few studies have investigated its efficacy in anaerobic short all-out activities. Moreover, there is still no consensus on which brain areas could provide the most favorable effects on different performance modalities. Accordingly, this study aimed to investigate the effects of anodal tDCS (a-tDCS) targeting the primary motor cortex (M1) or left dorsolateral prefrontal cortex (DLPFC) on physical performance, psychophysiological responses, and cognitive function in repeated all-out cycling. METHODS: In this randomized, crossover, and double-blind study, 15 healthy physically active men underwent a-tDCS targeting M1 or the left DLPFC or sham tDCS in separate days before performing three bouts of all-out 30s cycling anaerobic test. a-tDCS was applied using 2 mA for 20 min. Peak power, mean power, fatigue index, and EMG of the quadriceps muscles were measured during each bout. Heart rate, perceived exertion, affective valence, and arousal were recorded two minutes after each bout. Color-word Stroop test and choice reaction time were measured at baseline and after the whole anaerobic test. RESULTS: Neither tDCS montage significantly changed peak power, mean power, fatigue index, heart rate, affective valence, arousal, and choice reaction time (p> 0.05). a-tDCS over DLPFC significantly lowered RPE of the first bout (compared to sham; p=0.048, Δ=-12.5%) and third bout compared to the M1 (p=0.047, Δ=-12.38%) and sham (p=0.003, Δ=-10.5%), increased EMG of the Vastus Lateralis muscle during the second (p=0.016, Δ= +40.3%) and third bout (p=0.016, Δ= +42.1%) compared to sham, and improved the score of color-word Stroop test after the repeated all-out task (p=0.04, Δ= +147%). The qualitative affective response (valence and arousal) was also higher under the M1 and DLPFC compared to the sham. CONCLUSION: We concluded that tDCS targeting M1 or DLPFC does not improve repeated anaerobic performance. However, the positive effect of DLPFC montage on RPE, EMG, qualitative affective responses, and cognitive function is promising and paves the path for future research using different tDCS montages to see any possible effects on anaerobic performance. TRIAL REGISTRATION: This study was approved by the Ethics Committee of Razi University (IR.RAZI.REC.1400.023) and registered in the Iranian Registry of Clinical Trials (IRCT id: IRCT20210617051606N5; Registration Date: 04/02/2022).


Assuntos
Estimulação Transcraniana por Corrente Contínua , Masculino , Humanos , Córtex Pré-Frontal Dorsolateral , Irã (Geográfico) , Córtex Pré-Frontal , Cognição/fisiologia , Método Duplo-Cego , Fadiga , Desempenho Físico Funcional
11.
Front Physiol ; 14: 1146076, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324399

RESUMO

Determining the optimal load (OPTLOAD) in measuring mechanical peak power output (PPO) is important in assessment of anaerobic fitness. The main goals of this study were: 1) to examine estimated optimal load and PPO based on a force-velocity test and 2) to compare the PPO from the previous method with the Wingate Anaerobic Test (WAnT). The study involved 15 academic male athletes, aged 22.4 ± 2.3 (years), height 178.9 ± 6.8 (cm), and body weight 77.9 ± 12.2 (kg). They performed the 30-s WAnT (7.5% of body weight) during the first visit to the laboratory. Second to fourth session included a force-velocity test (FVT) involving three, 10-s all-out sprints. A randomized load ranging from 3 to 11 kg was used in each session for FVT. The OPTLOAD and PPO were computed using quadratic relationships based on power-velocity (P-v) and power-percent of body weight (P-%BM) and including three, four, five and nine sprints from FVT. The results showed non-difference in OPTLOAD [13.8 ± 3.2 (%BM); 14.1 ± 3.5 (%BM); 13.5 ± 2.8 (%BM); 13.4 ± 2.6 (%BM)] executed at three, four, five, and nine sprints (F3,56 = 0.174, p = 0.91, η2 = 0.01). The two-way ANOVA revealed that PPO were similar between tested models (P-%BM vs. P-v) independently from the numbers of sprints (F3,112 = 0.08, p = 0.99, η2 = 0.000). Moreover, the PPO measured in the WAnT (870.6 ± 179.1 W) was significantly lower compared with in P-v model (1,102.9 ± 242.5-1,134.2 ± 285.4 W) (F4,70 = 3.044, p = 0.02, η2 = 0.148). In addition, the PPO derived from P-%BM model (1,105.2 ± 245.5-1,138.7 ± 285.3 W) was significantly higher compared with the WAnT (F4,70 = 2.976, p = 0.02, η2 = 0.145). The findings suggest the potential utility of FVT for assessment of anaerobic capacity.

12.
Front Physiol ; 14: 1147321, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37123252

RESUMO

Purpose: This study aimed at comparing previous calculating formulas of maximal lactate accumulation rate ( ν La.max) and a modified formula of pure ν La.max (P ν La.max) during a 15-s all-out sprint cycling test (ASCT) to analyze their relationships. Methods: Thirty male national-level track cyclists participated in this study (n = 30) and performed a 15-s ASCT. The anaerobic power output (Wpeak and Wmean), oxygen uptake, and blood lactate concentrations (La-) were measured. These parameters were used for different calculations of ν La.max and three energy contributions (phosphagen, W PCr; glycolytic, W Gly; and oxidative, W Oxi). The P ν La.max calculation considered delta La-, time until Wpeak (tPCr-peak), and the time contributed by the oxidative system (tOxi). Other ν La.max levels without tOxi were calculated using decreasing time by 3.5% from Wpeak (tPCr -3.5%) and tPCr-peak. Results: The absolute and relative W PCr were higher than W Gly and W Oxi (p < 0.0001, respectively), and the absolute and relative W Gly were significantly higher than W Oxi (p < 0.0001, respectively); ν La.max (tPCr -3.5%) was significantly higher than P ν La.max and ν La.max (tPCr-peak), while ν La.max (tPCr-peak) was lower than P ν La.max (p < 0.0001, respectively). P ν La.max and ν La.max (tPCr-peak) were highly correlated (r = 0.99; R 2 = 0.98). This correlation was higher than the relationship between P ν La.max and ν La.max (tPCr -3.5%) (r = 0.87; R 2 = 0.77). ν La.max (tPCr-peak), P ν La.max, and ν La.max (tPCr -3.5%) were found to correlate with absolute Wmean and W Gly. Conclusion: P ν La.max as a modified calculation of ν La.max provides more detailed insights into the inter-individual differences in energy and glycolytic metabolism than ν La.max (tPCr-peak) and ν La.max (tPCr -3.5%). Because W Oxi and W PCr can differ remarkably between athletes, implementing their values in P ν La.max can establish more optimized individual profiling for elite track cyclists.

13.
Nutrients ; 15(10)2023 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-37242187

RESUMO

A pre-workout supplement's (PWS; 200 mg caffeine, 3.3 g creatine monohydrate, 3.2 g ß-alanine, 6 g citrulline malate and 5 g branched chained amino acid (BCAA) per dose) acute effects on the alactic (jumping, sprinting, agility), lactic (Running-Based Anaerobic Sprint Test, RAST) and aerobic performance (Yo-Yo Intermittent Recovery Test Level 1, Yo-Yo IRL1 VO2max) of well-trained basketball players was investigated in this double-blind placebo-controlled study. Thirty players (age 18-31 years, height 166-195 cm, weight 70.2-116.7 kg, body fat 10.6-26.4%) were allocated to pre-workout (PWS, n = 15) or placebo (PL, n = 15) groups. Half of the participants in each group performed the evaluations without PWS or PL, while the rest consumed PWS or PL 30 min before the assessments (1st trial) and vice versa (2nd trial). Significant improvements in counter-movement jump (CMJ) (PWS: 4.3 ± 2.1%; PL: 1.2 ± 1.0%), agility (PWS: -2.9 ± 1.8%; PL: 1.8 ± 1.7%), RAST average (PWS: 18.3 ± 9.1%; PL: -2.2 ± 2.0%), minimum power (PWS: 13.7 ± 8.9%; PL: -7.5 ± 5.9%), and fatigue index (PWS: -25.0 ± 0.9%; PL: -4.6 ± 0.6%) were observed in the PWS group vs. the PL group (p < 0.05). No differences were found regarding sprinting, aerobic performance, and blood lactate concentrations. Thus, although players' alactic and lactic anaerobic performance could be improved, peak power, sprinting and aerobic performance are not.


Assuntos
Desempenho Atlético , Basquetebol , Humanos , Adolescente , Adulto Jovem , Adulto , Resistência Física , Atletas , Ingestão de Alimentos
14.
Healthcare (Basel) ; 11(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36833157

RESUMO

The purpose of this study was to compare the impact of velocity-based resistance training (VBRT) and percentage-based resistance training (PBRT) on anaerobic ability, sprint performance, and jumping ability. Eighteen female basketball players from a Sport College were randomly divided into two groups: VBRT (n = 10) and PBRT (n = 8). The six-week intervention consisted of two sessions per week of free-weight back squats with linear periodization from 65% to 95%1RM. In PBRT, the weights lifted were fixed based on 1RM percentage, while in VBRT, the weights were adjusted based on individualized velocity profiles. The T-30m sprint time, relative power of countermovement jump (RP-CMJ), and Wingate test were evaluated. The Wingate test assessed peak power (PP), mean power (MP), fatigue index (FI), maximal velocity (Vmax), and total work (TW). Results showed that VBRT produced a very likely improvement in RP-CMJ, Vmax, PP, and FI (Hedges' g = 0.55, 0.93, 0.68, 0.53, respectively, p < 0.01). On the other hand, PBRT produced a very likely improvement in MP (Hedges' g = 0.38) and TW (Hedges' g = 0.45). Although VBRT showed likely favorable effects in RP-CMJ, PP, and Vmax compared to PBRT (p < 0.05 for interaction effect), PBRT produced greater improvements in MP and TW (p < 0.05 for interaction effect). In conclusion, PBRT may be more effective in maintaining high-power velocity endurance, while VBRT has a greater impact on explosive power adaptations.

15.
Artigo em Inglês | MEDLINE | ID: mdl-36673765

RESUMO

Background: In recent years, there has been intensive discussion about the positive effect of nicotine usage on enhancing sports performance. It is frequently applied through a non-burned tobacco form before physical activity. Nicotine is under the World Anti-Doping Agency (WADA) 2021 monitoring program. Therefore, study results that reveal either positive or negative effects are expected. This is the pilot study that reports the effect of 8 mg dose of nicotine on performance and perceived pain. Material and Methods: This research aimed to explore the oral intake effect of a high-nicotine dose (8 mg) on the maximum anaerobic performance and other selected physical performance parameters in healthy, well-trained adult athletes (n = 15, age 30.7 ± 3.6, BMI 25.3 ± 1.7). The cross-sectional study protocol included the oral administration of either sublingual nicotine or placebo tablets before the anaerobic load assessed by a standardized 30 s Wingate test of the lower limbs. Afterward, the Borg subjective perception of pain (CR 10) and Borg rating of perceived exertion (RPE) were evaluated. Wilcoxon signed-rank test was used for the analysis of data with a 0.05 level of significance. Results: The results revealed that oral administration of an 8 mg nicotine dose does not significantly improve any of the physical performance parameters monitored. We only reported the statistically significant positive effect in RPE (p = 0.03). Conclusion: Lower perception of pain intensity that we reported after nicotine application might be an important factor that affects performance. However, we did not report any improvement in physical performance parameters.


Assuntos
Nicotina , Dor , Adulto , Humanos , Nicotina/farmacologia , Projetos Piloto , Anaerobiose , Estudos Transversais , Dor/tratamento farmacológico , Atletas , Percepção da Dor , Esforço Físico
16.
Res Q Exerc Sport ; 94(3): 725-731, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35481945

RESUMO

Introduction: The aim of this study was to examine differences between a control warm-up and an Electric Muscle Stimulation (EMS)-induced warm-up in off-road cyclists when examining anaerobic performance measures from a repeated Wingate test (WAnT). Methods: Twelve trained off-road cyclists completed a randomized crossover study (age: 31 ± 10 years, height: 176.79 ± 6.09 cm, body mass: 74.57 ± 4.77 kg). Participants completed two randomized, separate testing sessions involving a control warm-up and an EMS warm-up before undergoing the repeated WAnT, which was used to collect anaerobic performance and physiolo- gical measures during both sessions. High-frequency EMS was applied to the knee extensor muscles for 4 min after a standardized warm-up during the EMS session. Results: Analysis revealed that there were no significant differences between mean power output, peak power output, and percentage decrement between the two sessions. The EMS session resulted in significantly lower average HR values and significantly lower differences in pre-to-post-test blood lactate values when compared to the control session. Discussion: According to the results of this study, an acute application of EMS is not a useful tool for off-road cyclists to improve power output or maintain anaerobic capacity. Hence, its use before competition is questionable.


Assuntos
Ciclismo , Exercício de Aquecimento , Humanos , Adulto Jovem , Adulto , Estudos Cross-Over , Anaerobiose , Ciclismo/fisiologia , Músculo Esquelético/fisiologia , Exercício de Aquecimento/fisiologia , Teste de Esforço/métodos
17.
Eur J Appl Physiol ; 123(1): 49-64, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36152058

RESUMO

PURPOSE: This study investigated the effects of both an active warm-up and the time-of-day variation on repeated-sprint performance. A second objective was to compare the post-exercise recovery between the experimental conditions. METHODS: Eleven male participants performed ten maximal cycling sprints (6 s each, with a 30-s interval between them) in the morning and late afternoon, either after a warm-up or control condition. The warm-up consisted of cycling for 10 min at 50% of the peak aerobic power. RESULTS: Rest measurements of rectal, muscle, and skin temperatures were higher in the afternoon compared to the morning (p < 0.05), with no significant differences in heart rate (p = 0.079) and blood lactate concentration (p = 0.300). Warm-up increased muscle temperature, heart rate, and lactate, and reduced skin temperature (all p < 0.001), though no significant differences were observed for rectal temperature (p = 0.410). The number of revolutions (p = 0.034, ηp2 = 0.375), peak (p = 0.034, ηp2 = 0.375), and mean (p = 0.037, ηp2 = 0.365) power of the first sprint (not the average of ten sprints) were higher in the afternoon compared to the morning, regardless of warm-up. However, beneficial performance effects of warming up were evident for the first (p < 0.001) and the average of ten sprints (p < 0.05), regardless of time of day. More remarkable changes during the 60-min post-exercise were observed for rectal temperature (p = 0.005) and heart rate (p = 0.010) in the afternoon than in the morning. CONCLUSION: Warming-up and time-of-day effects in enhancing muscular power are independent. Although warm-up ensured further beneficial effects on performance than the time-of-day variation, a faster post-exercise recovery was observed in the late afternoon.


Assuntos
Desempenho Atlético , Exercício de Aquecimento , Humanos , Masculino , Teste de Esforço , Tempo , Músculo Esquelético/fisiologia , Ácido Láctico
18.
Res Q Exerc Sport ; 94(4): 1035-1041, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36036823

RESUMO

Purpose: Ammonia inhalants (NH3) are anecdotally used in competition by athletes for their purported stimulant effects. However, evidence on the efficacy of NH3 is conflicting, and little to no studies to date have investigated its effect on repeated exercise. The purpose of this study was to examine the effects of NH3 on psychophysiological responses and performance during repeated high-intensity exercise. Methods: In a counterbalanced crossover design, physically active females completed two repeated high-intensity sprint trials with a different treatment: Control (CON; water) or Ammonia Inhalants (NH3; 0.33 cc). For each trial, participants completed 3 × 15s Wingate anaerobic tests (WAnT) separated by 2 min of active recovery. Prior to each WAnT, participants took a single 3-s inhale of the corresponding treatment. After the succession of each WAnT, heart rate (HR) and rate of perceived exertion (RPE) were documented. Subjective feelings of alertness and "psyched up" energy were measured using a visual analog scale. Trials were separated by at least 48 hr. Results: The results indicate that over the WAnTs, mean power (p = .017) and peak power (p = .006) were significantly higher with NH3 compared to CON despite a lack of changes in fatigue index (p = .928). HR (p = .101) and RPE (p = .897) were not different with varying treatments. Perceived alertness (p = .010) and psyched-up energy (p = .002) were significantly higher with NH3 versus CON. Conclusion: These findings provide empirical support for the use of NH3 to improve repeated high-intensity exercise performance in females that may be underpinned by alterations in subjective alertness and energy.


Assuntos
Amônia , Desempenho Atlético , Feminino , Humanos , Desempenho Atlético/fisiologia , Exercício Físico , Fadiga , Teste de Esforço
19.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-972145

RESUMO

@#Participation in exercise benefits health and fitness among Intellectual Disability (ID) individuals. Circuit training is one of the exercise programme that can be tailored by manipulating the intensity, time and types of exercise. The purpose of the present study is to examine the effects of six weeks of circuit training on anaerobic fitness and simple reaction time in ID individuals. Thirty participants with mild to moderate ID were selected from individuals who are registered with the Pusat Pemulihan dalam Komuniti (PDK) and Yayasan Orang Kurang Upaya (YOKUK) in the Kelantan state. Participants were randomly divided into Circuit Training and Control groups. Participants in Circuit Training group followed a circuit training exercise programme, two times per week for six weeks, whereas participants in Control group were not involved in circuit training and carried out their regular activities. The anaerobic peak power was significantly decreased (ƿ < 0.001) in Control group after six weeks. The anaerobic power of post-test was significantly improved (ƿ = 0.042) from the pre-test in Circuit Training group and it was also significantly higher (ƿ = 0.001) than Control group. There were no significant differences for the anaerobic capacity and simple reaction time between and within groups. Circuit training can be conducted to enhance anaerobic power in ID individuals, however longer participation may be needed to improve anaerobic capacity and simple reaction time.

20.
Int J Exerc Sci ; 16(2): 1334-1384, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38288402

RESUMO

This paper systematically reviews the latest evidence regarding Quercetin's (Q) effect following exercise performance, aerobic and anaerobic exercise, muscle-damaging bouts and highlights blood biomarkers associated with muscle damage and recovery. Google Scholar, Web of Science, and MedLine (PubMed) searches were conducted through July-December 2021. Peer-reviewed studies that investigated Q as a single ingredient or in combination with other ingredients at dosages of 500 mg - 3000 mg, ranging from 15 min-to-1 h prior to exercise bout or chronic dose (7 days - 8 weeks) of consumption were included. A total of 34 studies met the inclusion criteria for the review. Key results include significant performance improvements in the following: VO2max (n = 2), time to exhaustion (n = 4 articles), fatigue decrement (n = 1 article), muscle damage (n = 3 articles), strength, torque velocity, and neuromuscular performance (n = 3 articles), redox potential (n = 1 article), repeated sprint performance and oxygen extraction (n = 1). Q also caused a change in systemic biomarkers: decrease in creatine kinase (n = 2), c-reactive protein (n = 4), lactate dehydrogenase (n = 4), inflammatory markers (n = 3), lipid peroxidation (n = 3) in aerobic and anaerobic performance. Varied findings exist regarding the efficacy of Q supplementation on exercise performance and recovery outcomes. The source of Q, training status of subjects, and exercise protocol performed may contribute to the effectiveness of Q as an antioxidant, anti-inflammatory, or ergogenic agent in exercise.

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