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El propósito de este estudio fue evaluar la relación entre el rendimiento anaeróbico y la personalidad Grit en taekwondistas estadounidenses, su grado de influencia, así como las diferencias que puedan existir entre sexos. Este estudio tuvo una metodología cuantitativa, descriptiva-correlacional, realizada en una población de (n=121) taekwondistas, vinculados a la USAT. La personalidad Grit fue medida mediante la escala Grit, y el rendimiento anaeróbico a través de la prueba del sprint anaeróbico basado en la carrera (Rast). De acuerdo con los resultados se pudo identificar en hombres, una correlación positiva y significativa entre la capacidad y potencia anaeróbica con el Grit (p<0.005 y p<0.007 respectivamente). Asimismo, estas dos variables se relacionaron significativamente con el Grit (p<0.001) en el total de la muestra. En el caso de las mujeres, no hubo relaciones significativas. El índice de fatiga no presentó correlaciones significativas. La personalidad Grit influyó hasta un 14% en la capacidad y potencia anaeróbica en hombres (p<0.001 y p<0.002, respectivamente) y un 12% en estos dos mismos aspectos para la muestra total (p<0.000 en ambos casos). Finalmente, los hallazgos indican una relación entre la potencia, capacidad anaeróbica con la personalidad Grit en hombres y en el total de la muestra, con una influencia significativa del Grit en el rendimiento anaeróbico. No se encontraron tales relaciones en mujeres. Aunque no se hallaron diferencias significativas por sexo en el Grit, capacidad y potencia anaeróbica, sí que se encontró en el índice de fatiga, indicando una disparidad en la resistencia a la fatiga entre sexos.

The purpose of this study was to assess the relationship between anaerobic performance and Grit personality in American taekwondo practitioners, its degree of influence, as well as any differences that may exist between genders. This study employed a quantitative, descriptive-correlational methodology, conducted on a population of (n=121) taekwondo practitioners affiliated with the USAT. Grit personality was measured using the Grit Scale, and anaerobic performance was assessed through the Anaerobic Sprint Test based on running (Rast). According to the results, a positive and significant correlation between anaerobic capacity and power with Grit was identified in men (p<0.005 and p<0.007 respectively). Likewise, these two variables were significantly related to Grit (p<0.001) in the total sample. In the case of women, there were no significant relationships. The fatigue index showed no significant correlations. Grit personality influenced up to 14% in anaerobic capacity and power in men (p<0.001 and p<0.002, respectively) and 12% in these two aspects for the total sample (p<0.000 in both cases). Finally, the findings indicate a relationship between power, anaerobic capacity, and Grit personality in men and the total sample, with a significant influence of Grit on anaerobic performance. Such relationships were not found in women. Although no significant gender differences were found in Grit, anaerobic capacity, and power, differences were found in the fatigue index, indicating a disparity in fatigue resistance between genders.

O objetivo deste estudo foi avaliar a relação entre o desempenho anaeróbico e a personalidade Grit em praticantes de taekwondo americanos, seu grau de influência, bem como as diferenças que possam existir entre os sexos. Este estudo utilizou uma metodologia quantitativa, descritiva-correlacional, realizada em uma população de (n=121) praticantes de taekwondo afiliados à USAT. A personalidade Grit foi medida usando a Escala Grit, e o desempenho anaeróbico foi avaliado através do Teste de Sprint Anaeróbico baseado em corrida (Rast). De acordo com os resultados, foi possível identificar nos homens uma correlação positiva e significativa entre a capacidade e potência anaeróbica com o Grit (p<0.005 e p<0.007, respectivamente). Da mesma forma, essas duas variáveis estavam significativamente relacionadas ao Grit (p<0.001) na amostra total. No caso das mulheres, não foram encontradas relações significativas. O índice de fadiga não apresentou correlações significativas. A personalidade Grit influenciou até 14% na capacidade e potência anaeróbica em homens (p<0.001 e p<0.002, respectivamente) e 12% nesses dois aspectos para a amostra total (p<0.000 em ambos os casos). Finalmente, os achados indicam uma relação entre potência, capacidade anaeróbica e a personalidade Grit em homens e na amostra total, com uma influência significativa do Grit no desempenho anaeróbico. Tais relações não foram encontradas em mulheres. Embora não tenham sido encontradas diferenças significativas por sexo no Grit, capacidade e potência anaeróbica, foi encontrada diferença no índice de fadiga, indicando uma disparidade na resistência à fadiga entre os sexos.

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OBJECTIVE: To synthesize evidence about physical fitness levels in children with developmental coordination disorder (DCD) compared with typically developing (TD) children. METHODS: We searched four databases (PubMed, Scopus, Web of Science, and PsycINFO) for cross-sectional, case-control, and cohort studies comparing physical fitness between children with and without DCD. We assessed the methodological quality of the studies with the Newcastle-Ottawa Scale (NOS). We calculated Cohen's d effect sizes to provide clinical evidence of group differences in aerobic capacity, anaerobic capacity, muscle strength, body composition and flexibility. RESULTS: We included 32 studies for qualitative synthesis after applying eligibility criteria. All selected studies ranged from moderate to high research quality. Effect sizes in favor of typically developing children over children with DCD were large for aerobic capacity (d = 1.15), anaerobic capacity (d = 0.90), and muscle strength (d = 0.79), and small for body composition (d = 0.43) and flexibility (d = 0.21) outcomes. CONCLUSION: Children with DCD presented significantly lower physical fitness than their typically developing peers, particularly in aerobic and anaerobic capacity and in muscle strength.

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The anaerobic metabolism determination is complex and the applied methodologies present limitations. Thus, the purpose of this study was to investigate the effects of different calculations (MAOD vs. AOD) on the anaerobic contribution using the dynamic knee extension. Twenty-four male were recruited [Mean (SD); age 27 (1) years, body mass 90 (3) kg, height 181 (2) cm]. This study was divided into two independent experiments (EXP1: one-legged; EXP2: two-legged). In both experiments, it was performed a graded exercise test to determine maximal power (MP-GXT); 2-4 submaximal efforts (VO2-intensity relationship); and an exhaustive effort. The theoretical energy demand for the exhaustive effort (TEDex) was constructed from the submaximal efforts. Therefore, MAOD was assumed as the difference between the TEDex and the accumulated VO2 (AVO2). In contrast, the energy demand for AOD was calculated as the product between VO2 at the end of exercise and time to exhaustion (TEDaod). Thus, AOD was assumed as the difference between TEDaod and AVO2. Bayesian paired t-test was used to compare the differences between the applied methods. Also, correlations between the anaerobic indices and performance were verified. In EXP1, AOD was higher than MAOD [1855 (741) vs. 434 (245); BF10 = 2925; ES = 2.5]. In contrast, in EXP2, MAOD was higher than AOD [2832 (959) vs. 1636 (549); BF10 = 3.33; ES = 1.4]. Also, AOD was correlated to performance (r = .59; BF10 = 4.38). We concluded that MAOD and AOD are a distinct phenomenon and must be utilized according to the exercise model.

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Limited information is available regarding the role of anaerobic metabolism capacity on GOLD 1 and 2 COPD patients during upper limb exercise. We aimed to compare the upper limb anaerobic power capacity, blood lactate concentration, cardiovascular and respiratory responses, in male COPD patients versus healthy subjects during the 30-s Wingate anaerobic test (WAnT). The rate of fatigue and time constant of the power output decay (τ, tau) were also calculated and a regression analysis model was built to assess the predictors of τ in these patients. Twenty-four male COPD patients (post-bronchodilator FEV1 73.2 ± 15.3% of predicted) and 17 healthy subjects (FEV1 103.5 ± 10.1% of predicted) underwent the WAnT. Measurements were performed at rest, at the end of the WAnT, and during 3' and 5' of recovery time. Peak power (p = 0.04), low power (p = 0.002), and mean power output (p = 0.008) were significantly lower in COPD patients than in healthy subjects. Power output decreased exponentially in both groups, but at a significantly faster rate (p = 0.007) in COPD patients. The time constant of power decay was associated with resistance (in ohms) and fat-free mass (r2 = 0.604, adjusted r2 = 0.555, and p = 0.002). Blood lactate concentration was significantly higher in healthy subjects at the end of the test, as well as during 3' and 5' of recovery time (p < 0.01). Compared with healthy subjects, COPD patients with GOLD 1 and 2 presented lower upper limb anaerobic capacity and a faster rate of power output decrease during a maximal intensity exercise. Also, the WAnT proved to be a valid tool to measure the upper limb anaerobic capacity in these patients.

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ABSTRACTSodium bicarbonate (SB) is considered an effective ergogenic supplement for improving high-intensity exercise capacity and performance, although recent data suggests that women may be less amenable to its ergogenic effects than men. Currently, an apparent paucity of data on women means no consensus exists on whether women benefit from SB supplementation. The aim of the current study was to quantify the proportion of the published literature on SB supplementation that includes women, and to synthesise the evidence regarding its effects on blood bicarbonate and exercise performance in women by performing a systematic review and meta-analysis. Electronic searches of the literature were undertaken using three databases (MEDLINE, Embase, SPORTDiscus) to identify relevant articles. All meta-analyses were performed within a Bayesian framework. A total of 149 SB articles were identified, 11 of which contained individual group data for women. Results indicated a pooled blood bicarbonate increase of 7.4 [95%CrI: 4.2-10.4 mmol·L-1] following supplementation and a pooled standardised exercise effect size of 0.37 [95%CrI: -0.06-0.92]. The SB literature is skewed, with only 20% (30 studies) of studies employing female participants, of which only 11 studies (7.4%) provided group analyses exclusively in women. Despite the small amount of available data, results are consistent in showing that SB supplementation in women leads to large changes in blood bicarbonate and that there is strong evidence for a positive ergogenic effect on exercise performance that is likely to be small to medium in magnitude.HighlightsThis study aimed to quantify the proportion of the published literature on sodium bicarbonate supplementation that includes women and to synthesise the evidence regarding its ergogenic effect on women, using a systematic review and meta-analytic approach.The sodium bicarbonate literature is skewed, with only 30 studies (20%) employing female participants, of which only 11 studies (7.4%) provided group analyses exclusively in women.Despite the small amount of available data, results are consistent in showing that sodium bicarbonate supplementation in women leads to large changes in blood bicarbonate and that there is strong evidence for a positive ergogenic effect on exercise performance that is likely small to medium in magnitude.Based on these findings, we do not believe there is any evidence to support sex-specific sodium bicarbonate dosing recommendations and that current recommendations of 0.2-0.3 g·kg-1BM of SB taken 60-180 min prior to high-intensity exercise appear appropriate for the female athlete.

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Abstract Aim: To investigate the effects of caffeine (CAF) ingestion on anaerobic work capacity (AWC) and muscular endurance in the bench press exercise at predictive intensities equivalent to 20, 25, and 30% of 1RM. Methods: Thirteen males (age: 23 ± 3 years; body mass 83.5 ± 4.9 kg; height 172.8 ± 5.0 cm and 1RM 82 ± 24 kg) had their 1RM test evaluated in the bench press exercise and the time until failure was performed at intensities equivalent to 20%, 25%, and 30% of 1RM to CAF (350mg) or placebo (PLA, cellulose). AWC was measured from the linear equation: "Force = Critical Force + (AWC x 1/timeout)". Results: CAF enhanced the time until failure at 20% of 1RM (PLA = 202.6 ± 29.1s; CAF = 243.2 ± 20.6s), but there was no ergogenic effect at 25% (PLA = 188.8 ± 23.5 s; CAF = 195.6 ± 27.1 s), and 30% (PLA = 147.4 ± 15.8 s; CAF = 145.4 ± 14.8 s). AWC in CAF was lower than PLA (PLA = 6378.0 ± 1214.9 J; CAF = 3246.4 ± 1389.7 J; p = 0.03; Effect size = 0.88). Critical Force (N) was not different between treatments PLA 29.97 ± 11.54% of 1RM and CAF 3.74 ± 3.69% of 1 RM (p=0.47; Effect size= 0.28). Conclusion: Acute CAF intake (350mg) reduces the AWC and increases the time until failure at 20% of 1 RM, but not Critical Force and muscular endurance at 25% and 30% of 1 RM in the bench press.

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BACKGROUND: One of the most popular high-intensity interval exercises is the called "Tabata Protocol". However, most investigations have limitations in describing the work intensity, and this fact appears to be due to the protocol unfeasibility. Furthermore, the physiological demands and energetic contribution during this kind of exercise remain unclear. METHODS: Eight physically active students (21.8 ± 3.7 years) and eight well-trained cycling athletes (27.8 ± 6.4 years) were enrolled. In the first visit, we collected descriptive data and the peak power output (PPO). On the next three visits, in random order, participants performed interval training with the same time structure (effort:rest 20s:10s) but using different intensities (115%, 130%, and 170% of PPO). We collected the number of sprints, power output, oxygen consumption, blood lactate, and heart rate. RESULTS: The analysis of variance for multivariate test (number of sprints, power output, blood lactate, peak heart rate and percentage of maximal heart rate) showed significant differences between groups (F = 9.62; p = 0.001) and intensities (F = 384.05; p < 0.001), with no interactions (F = 0.94; p = 0.57). All three energetic contributions and intensities were different between protocols. The higher contribution was aerobic, followed by alactic and lactic. The aerobic contribution was higher at 115%PPO, while the alactic system showed higher contribution at 130%PPO. In conclusion, the aerobic system was predominant in the three exercise protocols, and we observed a higher contribution at lower intensities.

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The study investigated the influence of ß-alanine supplementation during a high-intensity interval training (HIIT) program on repeated sprint ability (RSA) performance. This study was randomized, double-blinded, and placebo controlled. Eighteen men performed an incremental running test until exhaustion (TINC) at baseline and followed by 4-wk HIIT (10 × 1-min runs 90% maximal TINC velocity [1-min recovery]). Then, participants were randomized into two groups and performed a 6-wk HIIT associated with supplementation of 6.4 g/day of ß-alanine (Gß) or dextrose (placebo group; GP). Pre- and post-6-wk HIIT + supplementation, participants performed the following tests: 1) TINC; 2) supramaximal running test; and 3) 2 × 6 × 35-m sprints (RSA). Before and immediately after RSA, neuromuscular function was assessed by vertical jumps, maximal isometric voluntary contractions of knee extension, and neuromuscular electrical stimulations. Muscle biopsies were performed to determine muscle carnosine content, muscle buffering capacity in vitro (ßmin vitro), and content of phosphofructokinase (PFK), monocarboxylate transporter 4 (MCT4), and hypoxia-inducible factor-1α (HIF-1α). Both groups showed a significant time effect for maximal oxygen uptake (Gß: 6.2 ± 3.6% and GP: 6.5 ± 4.2%; P > 0.01); only Gß showed a time effect for total (-3.0 ± 2.0%; P = 0.001) and best (-3.3 ± 3.0%; P = 0.03) RSA times. A group-by-time interaction was shown after HIIT + Supplementation for muscle carnosine (Gß: 34.4 ± 2.3 mmol·kg-1·dm-1 and GP: 20.7 ± 3.0 mmol·kg-1·dm-1; P = 0.003) and neuromuscular voluntary activation after RSA (Gß: 87.2 ± 3.3% and GP: 78.9 ± 12.4%; P = 0.02). No time effect or group-by-time interaction was shown for supramaximal running test performance, ßm, and content of PFK, MCT4, and HIF-1α. In summary, ß-alanine supplementation during HIIT increased muscle carnosine and attenuated neuromuscular fatigue, which may contribute to an enhancement of RSA performance.NEW & NOTEWORTHY ß-Alanine supplementation during a high-intensity interval training program increased repeated sprint performance. The improvement of muscle carnosine content induced by ß-alanine supplementation may have contributed to an attenuation of central fatigue during repeated sprint. Overall, ß-alanine supplementation may be a useful dietary intervention to prevent fatigue.

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This study aimed to investigate the effects of short-duration creatine monohydrate supplementation on anaerobic capacity (AC), anaerobic energy pathways, and time-to-exhaustion during high-intensity running. Fourteen healthy men underwent a graded exercise test (GXT) followed by a O2max confirmation test, 5 submaximal efforts, and 4 supramaximal running bouts at 115% of V ˙ O2max intensity (the first two supramaximal sessions were applied as familiarization trials) to measure the AC using two procedures; the maximum accumulated oxygen deficit (MAOD) and non-oxidative pathways energetics sum (AC[La-]+EPOCfast). The investigation was conducted in a single-blind and placebo-controlled manner, with participants performing the efforts first after being supplemented with a placebo (dextrose 20 g⋅day-1 for 5 days), and then, after a 7 day "placebo" washout period, they started the same procedure under creatine supplementation (20 g⋅day-1 for 5 days. This order was chosen due to the prolonged washout of creatine. MAOD was not different between placebo (3.35 ± 0.65 L) and creatine conditions (3.39 ± 0.79 L; P = 0.58) and presented a negligible effect [effect size (ES) = 0.08], similar to, AC[La-]+EPOCfast (placebo condition (3.66 ± 0.79 Land under creatine ingestion 3.82 ± 0.85 L; P = 0.07) presenting a small effect (ES = 0.20). The energetics from the phosphagen pathway increased significantly after creatine supplementation (1.66 ± 0.40 L) compared to the placebo condition (1.55 ± 0.42 L; P = 0.03). However, the glycolytic and oxidative pathways were not different between conditions. Furthermore, time to exhaustion did not differ between placebo (160.79 ± 37.76 s) and creatine conditions (163.64 ± 38.72; P = 0.49). Therefore, we can conclude that creatine supplementation improves the phosphagen energy contribution, but with no statistical effect on AC or time to exhaustion in supramaximal running.

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The purpose of this study was to investigate the use of a single 3-min all-out maximal effort to estimate anaerobic capacity (AC) through the lactate and excess post-exercise oxygen consumption (EPOC) response methods (AC[La-]+EPOCfast) on a cycle ergometer. Eleven physically active men (age = 28.1 ± 4.0 yrs, height = 175.1 ± 4.2 cm, body mass = 74.8 ± 11.9 kg and ⩒O2max = 40.7 ± 7.3 mL kg-1 min-1), participated in the study and performed: i) five submaximal efforts, ii) a supramaximal effort at 115% of intensity of ⩒O2max, and iii) a 3-min all-out maximal effort. Anaerobic capacity was estimated using the supramaximal effort through conventional maximal accumulated oxygen deficit (MAOD) and also through the sum of oxygen equivalents from the glycolytic (fast component of excess post-exercise oxygen consumption) and phosphagen pathways (blood lactate accumulation) (AC[La-]+EPOCfast), while during the 3-min all-out maximal effort the anaerobic capacity was estimated using the AC[La-]+EPOCfast procedure. There were no significant differences between the three methods (p > 0.05). Additionally, the anaerobic capacity estimated during the 3-min all-out effort was significantly correlated with the MAOD (r = 0.74; p = 0.009) and AC[La-]+EPOCfast methods (r = 0.65; p = 0.029). Therefore, it is possible to conclude that the 3-min all-out effort is valid to estimate anaerobic capacity in physically active men during a single cycle ergometer effort.

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Aim: The present study aimed to verify if there is a difference between genders in anaerobic capacity estimated by energetic equivalents of glycolytic and phosphagen pathways (AC[La-]+EPOCfast). Methods: In this way, 8 men and 8 women (physical education students) were subjected to the following sequence of tests: session 1) graded exercise test to measure the maximal oxygen consumption (VÖ½ O2max) and intensity associated with VÖ½ O2max (iVÖ½ O2max); sessions 2 to 3) familiarization with supramaximal effort at 115% of iVÖ½ O2max; session 4) supramaximal effort at 115% of iVÖ½ O2max to measure AC[La-]+EPOCfast. Results: The AC[La-]+EPOCfast was lower in women compared to men when expressed in absolute and relative values (-38.11%; p=0.01 and -25.71%; p=0.03, respectively). A non-significant difference was observed in performance in the supramaximal effort (-12.08%; p=0.15), besides which, a likely negative inference was observed when comparing women to men. In addition, energetic equivalents of the glycolytic pathway (e[La- ]) were also lower in women when expressed in relative and absolute values (-47.01%; p=0.001 and -36.71%; p=0.001, respectively), however no statistical difference was found for energetic equivalents of the phosphagen pathway (ePCr) (p>0.05). Conclusion: The AC[La-]+EPOCfast is lower in women compared to men, mainly due to differences in the glycolytic pathway.(AU)

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The aim of this study was to verify the effects of caffeine on anaerobic capacity estimated by the sum of the estimated glycolytic [E[La]] and phosphagen [EPCr] metabolism based on blood lactate and excess post-oxygen consumption responses (AC[La-]+EPOCfast). Fourteen male cyclists were submitted to a graded exercise test to determine the maximal oxygen uptake ( V ° O 2 m a x ) and intensity associated with   V ° O 2 m a x (i V ° O 2 m a x ). Subsequently, the participants performed two supramaximal efforts at 115% of i V ° O 2 m a x to determine the AC[La-]+EPOCfast, after previous supplementation with caffeine (6 mg·kg-1) or a placebo (dextrose), in a cross over, randomized, double blind, and placebo-controlled design. The time to exhaustion was higher in the caffeine (186.6 ± 29.8 s) than in the placebo condition (173.3 ± 25.3 s) (p = 0.006) and a significant correlation was found between them (r = 0.86; P = 0.00008). Significant differences were not found between AC[La-]+EPOCfast values from the placebo (4.06 ± 0.83 L and 55.2 ± 5.7 mL·kg-1) and caffeine condition (4.00 ± 0.76 L and 54.6 ± 5.4 mL·kg-1); however, a significant correlation was observed only for AC[La-]+EPOCfast expressed in absolute values (r = 0.74; p < 0.002). The E[La] and EPCr also presented no significant differences and they were significantly correlated (r = 0.82 and r = 0.55, respectively; p < 0.05). We conclude based on the overall comparison of mean values between two treatments that acute caffeine ingestion improves the time to exhaustion but does not affect anaerobic capacity estimation.

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Abstract Background/Aim Determine critical speed (CS) and running distance above CS (D'), as estimated from the 3-min all-out running test (3MT) is reliable and predictive of CS and D' determined from time trials. Methods Seven males (26 ± 5 years, VO2max: 56.6 ± 4.1 ml·kg-1·min-1) completed an incremental treadmill test, three separate time trials (Tlim) of 800, 1600, and 2400m to determine CS and D', and two 3MTs to estimate CS and D'. Results Estimates of trial 1 (CS =3.90±0.41 m·s-1, D'=176±42 m) and trial 2 (CS=3.89 ± 0.48 m·s-1, D' = 183±35 m) of the 3MT did not differ. Estimates of CS (ICC=0.95, CV=2.97%) and D' (ICC=0.93, CV=5.12%) from the 3MT were reliable. The 3MT trials provided valid estimates of CS as determined using regression of the three time trials (ICCs ranged 0.88-0.93, TE ranged 0.13-0.15 m·s-1, CV ranged 3.32-4.76%). The 3 MT underestimated D' by∼16%, a difference exceeding the test-retest variability. Conclusions Estimates of CS were valid and reliable; however, assessment of D' from the 3MT may not estimate anaerobic capacity accurately.

Resumo Antecedentes/Objetivo Determinar se a velocidade crítica (CS) e a distância acima da CS (D'), estimadaso pelo teste de três minutos máximo (3MT) é confiável e preditiva de CS e D' determinada a partir dos modelos lineares. Métodos Sete homens (26 ± 5 anos, VO2max:56,6 ± 4,1 ml·kg-1·min-1) completaram um teste incremental em esteira, três tomadas de tempo separadamente para 800, 1.600 e 2.400 m, para determinar CS e D' e 2 3MTs para estimar CS e D'. Resultados O primeiro 3 MT (CS = 3,90 ± 0,41 m·s-1, D' = 176 ± 42m) e o segundo 3 MT (CS = 3,89 ± 0,48 m·s-1, D' = 183 ± 35m) não foram diferentes. Estimativas do CS (ICC = 0,95, CV = 2,97%) e D' (ICC = 0,93, CV = 5,12%) a partir de 3 MT eram confiáveis. Os 3 MTs forneceram estimativas válidas de CS (ICC variou de 0,88-0,93, variaram de 0,13 a 0,15 ms TE, CV variou de 3,32 a 4,76%); 3 MT subestimou D' em ∼16%, uma diferença maior de variabilidade teste-reteste. Conclusões Estimativas CS são válidas e confiáveis. No entanto, a avaliação de D' a partir do 3MT não pode estimar com precisão a capacidade anaeróbica.

Antecedentes/Objetivos Determinar si la velocidad crítica (VC) y la distancia por encima de la VC (D'), según la estimación de la prueba de 3 minutos máximos (3MT) es fiable y predictiva de la VC y la D' determinada a partir de los mejores tiempos de carrera personales. Métodos Siete varones (26 ± 5 años, VO2máx: 56,6 ± 4,1 ml·kg-1·min-1) completaron una prueba progresiva en la cinta de correr, con tres períodos de tiempo separados de 800, 1.600 y 2.400 m para determinar la VC y la D' y dos 3MT para estimar la VC y la D'. Resultados Las estimaciones del ensayo 1 (VC = 3,90 ± 0,41 m·s-1, D' = 176 ± 42 m) y del ensayo 2 (VC = 3,89 ± 0,48 m·s-1, D' = 183 ± 35 m) de la prueba 3MT no fueron diferentes. Las estimaciones de la VC (ICC = 0,95; CV = 2,97%) y D' (ICC = 0,93; CV = 5,12%) a partir de la prueba 3MT fueron fiables. Las pruebas 3MT proporcionaron estimaciones válidas de la VC, como se determinó mediante regresión de las tres pruebas de tiempo (ICC se clasificaron desde 0,88 hasta 0,93 y la TE osciló entre 0,13 y 0,15 m.s-1, la CV varió del 3,32 al 4,76%). La D' 3MT subestimó el ∼16%, una diferencia superior a la variabilidad test-retest. Conclusiones Las estimaciones de VC fueron válidas y fiables; Sin embargo, la evaluación de D' desde la prueba de 3MT no puede estimar con precisión la capacidad anaeróbica.

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Goalball is a Paralympic sport involving people with visual impairment. Little is known about the physical fitness of elite players of this sport, as previous studies only evaluated body composition and aerobic capacity. Thus, the aim of this study was to describe the performance of elite goalball players in different physical tests and to look for relationships between them. Eleven elite Brazilian goalball players, seven males and four females, were evaluated for body composition, maximal handgrip isometric force (MHGF), countermovement jump (CMJ), throwing velocity (TV) and the Yo-Yo intermittent recovery test level 1 (Yo-Yo IR1). Players produced 41.54 ± 8.41 kgf in MHGF, 34.81 ± 7.2 cm in CMJ, 14.21 ± 1.89 m∙s-1 in TV, and 505 ± 313 m in Yo-Yo IR1, with an estimated maximum oxygen consumption (VO2max) of 40.64 ± 2.63 mL∙kg-1∙min-1. Most performance tests exhibited moderate to high correlations among them, while the percentage of body fat correlated with both the CMJ and Yo-Yo IR1 results. The current study reveals that CMJ could be a valuable monitoring tool as it was correlated with all other performance tests. The highest correlation observed was with TV (r = 0.754; p < 0.05), which is a key capacity in goalball. Moreover, high levels of body fat could be detrimental to anaerobic performance.

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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.

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The purpose of the study was to investigate the sensitivity of an alternative maximal accumulated oxygen deficit (MAODALT) method to discriminate the "anaerobic" capacity while comparing: least trained (LT) participants (n = 12), moderately trained (MT) participants (n = 12), endurance trained (ET) participants (n = 16), and rugby (RG) players (n = 11). Participants underwent a graded exercise test on a treadmill and a supramaximal effort for assessing MAODALT. MAODALT was calculated as the sum of oxygen equivalents from the phosphagen and glycolytic metabolic pathways. MAODALT was significantly higher (P < 0.05) in RG (64.4 ± 12.1 mL · kg-1) than in ET (56.8 ± 5.4 mL · kg-1; effect size [ES] = 0.77; +13.5%), MT (53.8 ± 5.3 mL · kg-1; ES = 1.08; +19.8%), and LT (49.9 ± 4.5 mL · kg-1; ES = 1.50; +36.4%). In addition, the magnitude-based inference analysis revealed that MAODALT was likely (LT vs. MT), very likely (MT vs. RG, and ET vs. RG) and most likely (LT vs. ET, and LT vs. RG) different between all groups, except for MT and ET, which presented an unclear difference. In conclusion, MAODALT was sensitive enough to distinguish the "anaerobic" capacity in individuals with different training status, especially for RG players compared with LT participants and MT participants.

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ABSTRACT Objective: This study evaluated the effect of carbohydrate intake on time to exhaustion and anaerobic contribution during supramaximal exercise on a cycle ergometer. Methods: The sample comprised ten participants with a mean age of 23.9±2.5 years, mean body mass of 75.1±12.3 kg, mean height of 170.0±1.0 cm, and mean body fat of 11.3±5.2%. The participants underwent an incremental test to determine maximal oxygen uptake and maximum power output, and two supramaximal tests with a constant load of 110% of the maximum power output to exhaustion. Thirty minutes before the supramaximal tests the participants consumed carbohydrates (2 g.kg-1) or placebo. Results: The times to exhaustion of carbohydrate and placebo did not differ (carbohydrate: 170.7±44.6s; placebo: 156.1±26.7s, p=0.17; effect size=0.39). Similarly, the anaerobic contributions of the two treatments did not differ (carbohydrate: 3.0±0.9 L; placebo: 2.7±1.1 L, p=0.23; effect size=0.29). Conclusion: Carbohydrate intake was not capable of increasing time to exhaustion and anaerobic contribution in physically active men cycling at 110% of maximum power output.

RESUMO Objetivo: Este estudo foi conduzido com o intuito de verificar o efeito da ingestão de carboidrato sobre o tempo de exaustão e a contribuição anaeróbia durante o exercício supramáximo em uma bicicleta ergométrica. Métodos: Dez participantes fizeram parte da amostra (idade: 23,9±2,5 anos; massa corporal: 75,1±12,3 kg; estatura: 170,0±1,0 cm; gordura corporal: 11,3±5,2%). Todos realizaram um teste incremental para determinar o consumo máximo de oxigênio e a potência máxima e dois testes supramáximos com carga constante de 110% da potência máxima até a exaustão. Os participantes ingeriram carboidrato (2 g.kg-1) ou placebo 30 minutos antes dos testes supramáximos. Resultados: Não houve diferença significativa no tempo de exaustão entre carboidrato e placebo (carboidrato: 170,7±44,6s; placebo: 156,1±26,7s, p=0,17; effect size=0,39). De forma similar, não houve diferença significativa na contribuição anaeróbia entre as condições (carboidrato: 3,0±0,9 L; placebo: 2,7±1,1 L, p=0,23; effect size=0,29). Conclusão: A ingestão de carboidrato não foi capaz de aumentar o tempo até a exaustão e a contribuição anaeróbia em exercícios à 110% da potência máxima em homens fisicamente ativos.

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The purpose of this study was to investigate the acute effects of photobiomodulation therapy using cluster light-emitting diodes (LEDT; 104 diodes) (wavelength 660 and 850 nm; energy density 1.5 and 4.5 J/cm(2); energy 60 J at each point; total energy delivered 600 J) on alternative maximal accumulated oxygen deficit (MAODALT) and time to exhaustion, during a high-intensity running effort. Fifteen moderately active and healthy males (age 25.1 ± 4.4 years) underwent a graded exercise test and two supramaximal exhaustive efforts at 115 % of the intensity associated with maximal oxygen uptake performed after acute LEDT or placebo irradiation in a double-blind, crossover, and placebo-controlled study design. The MAODALT was assumed as the sum of both oxygen equivalents estimated from the glycolytic and phosphagen metabolism pathways during each supramaximal effort. For the statistical analysis, a paired t test was used to determine differences between the treatments. The significance level was assumed as 95 %. In addition, a qualitative analysis was used to determine the magnitude of differences between groups. No significant differences were found for the values of oxygen equivalents from each energetic metabolism (P ≥ 0.28), for MAODALT values between the LEDT and placebo conditions (P ≥ 0.27), or for time to exhaustion (P = 0.80), except for the respiratory exchange ratio (P = 0.01). The magnitude-based inference of effect size reported only a possibly negative effect of photobiomodulation on MAODALT when expressed in units relative to body mass and on the glycolysis pathway (26 %). In summary, LEDT after a high-intensity running effort did not alter the MAODALT, metabolic energy pathways, or high-intensity running performance.

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The aim of the present study was to investigate the effects of acute administration of taurine overload on time to exhaustion (TTE) of high-intensity running performance and alternative maximal accumulated oxygen deficit (MAODALT). The study design was a randomized, placebo-controlled, crossover design. Seventeen healthy male volunteers (age: 25 ± 6 years; maximal oxygen uptake: 50.5 ± 7.6 mL·kg(-1)·min(-1)) performed an incremental treadmill-running test until voluntary exhaustion to determine maximal oxygen uptake and exercise intensity at maximal oxygen uptake. Subsequently, participants completed randomly 2 bouts of supramaximal treadmill-running at 110% exercise intensity at maximal oxygen uptake until exhaustion (placebo (6 g dextrose) or taurine (6 g) supplementation), separated by 1 week. MAODALT was determined using a single supramaximal effort by summating the contribution of the phosphagen and glycolytic pathways. When comparing the results of the supramaximal trials (i.e., placebo and taurine conditions) no differences were observed for high-intensity running TTE (237.70 ± 66.00 and 277.30 ± 40.64 s; p = 0.44) and MAODALT (55.77 ± 8.22 and 55.06 ± 7.89 mL·kg(-1); p = 0.61), which seem to indicate trivial and unclear differences using the magnitude-based inferences approach, respectively. In conclusion, acute 6 g taurine supplementation before exercise did not substantially improve high-intensity running performance and showed an unclear effect on MAODALT.

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The aim of the study was to investigate the effects of acute supplementation of sodium bicarbonate (NaHCO3) on maximal accumulated oxygen deficit (MAOD) determined by a single supramaximal effort (MAODALT) in running and the correlation with 200- and 400-m running performances. Fifteen healthy men (age, 23 ± 4 years; maximal oxygen uptake, 50.6 ± 6.1 mL·kg(-1)·min(-1)) underwent a maximal incremental exercise test and 2 supramaximal efforts at 110% of the intensity associated with maximal oxygen uptake, which was carried out after ingesting either 0.3 g·kg(-1) body weight NaHCO3 or a placebo (dextrose) and completing 200- and 400-m performance tests. The study design was double-blind, crossover, and placebo-controlled. Significant differences were found between the NaHCO3 and placebo conditions for MAODALT (p = 0.01) and the qualitative inference for substantial changes showed a very likely positive effect (98%). The lactic anaerobic contribution in the NaHCO3 ingestion condition was significantly higher (p < 0.01) and showed a very likely positive effect (99% chance), similar to that verified for peak blood lactate concentration (p < 0.01). No difference was found for time until exhaustion (p = 0.19) or alactic anaerobic contribution (p = 0.81). No significant correlations were observed between MAODALT and 200- and 400-m running performance tests. Therefore, we can conclude that both MAODALT and the anaerobic lactic metabolism are modified after acute NaHCO3 ingestion, but it is not correlated with running performance.

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