Effects of Paracetamol (Acetaminophen) Ingestion on Endurance Performance: A Systematic Review and Meta-Analysis

Several studies explored the effects of paracetamol (acetaminophen) ingestion on endurance performance, but their findings are conflicting. Therefore, this review aimed to conduct a meta-analysis examining the effects of paracetamol ingestion on endurance performance. Five databases were searched to find relevant studies. The PEDro checklist was used to assess the methodological quality of the included studies. Data reported in the included studies were pooled in a random-effects meta-analysis. A total of ten studies with good or excellent methodological quality were included in the meta-analysis (pooled n = 141). All included studies had a randomized, double-blind, crossover design. In the main meta-analysis, there was no significant difference between the effects of placebo and paracetamol on endurance performance (Cohen’s d = 0.09; 95% confidence interval (CI): −0.04, 0.22; p = 0.172). However, an ergogenic effect was found when we considered only the studies that provided paracetamol 45 to 60 min before exercise (Cohen’s d = 0.14; 95% CI: 0.07, 0.21; p < 0.001). In a subgroup analysis that focused on time-to-exhaustion tests, there was a significant ergogenic effect of paracetamol ingestion (Cohen’s d = 0.19; 95% CI: 0.06, 0.33; p = 0.006). There was no significant difference between placebo and paracetamol in a subgroup analysis that focused on time trial tests (Cohen’s d = 0.05; 95% CI: −0.12, 0.21; p = 0.561). In conclusion, paracetamol ingestion appears to enhance performance (a) in time-to-exhaustion endurance tests and (b) when consumed 45 to 60 min before exercise.

Ergogenic Effects of Acute Caffeine Intake on Muscular Endurance and Muscular Strength in Women: A Meta-Analysis

This meta-analysis aimed to explore the effects of caffeine ingestion on muscular endurance and muscular strength in women. Five databases were searched to find relevant studies. A random-effects meta-analysis of standardized mean differences (SMD) was performed for data analysis. Subgroup meta-analyses explored the effects of caffeine on upper-body and lower-body muscular endurance and muscular strength. Eight crossover placebo-controlled studies were included in the review. In the main meta-analysis that considered data from all included studies, there was a significant ergogenic effect of caffeine on muscular endurance (SMD = 0.25; p = 0.027) and muscular strength (SMD = 0.18; p < 0.001). In a subgroup analysis that considered only upper-body exercises, there was a significant ergogenic effect of caffeine on muscular endurance (SMD = 0.20; p = 0.007) and muscular strength (SMD = 0.17; p < 0.001). In a subgroup analysis that considered only lower-body exercises, there was no significant difference between caffeine and placebo for muscular endurance (SMD = 0.43; p = 0.092) or muscular strength (SMD = 0.16; p = 0.109). The main finding of this meta-analysis is that caffeine ingestion has a significant ergogenic effect on muscular endurance and muscular strength in women. The effects reported in this analysis are similar to those previously observed in men and suggest that women may use caffeine supplementation as an ergogenic aid for muscular performance. Future research is needed to explore the effects of caffeine on lower-body muscular endurance and muscular strength in this population.

Effects of Nutritional Supplements on Judo‐Related Performance: A Review

The potential ergogenic effect of nutritional supplements depends on their dosage and the type of exercise executed. Aiming at reviewing the research literature regarding sport supplements utilized in judo in order to improve performance, a literature search was performed at the following databases: Dialnet, PubMed, Scielo, Scopus and SportDiscus. A total of 11 articles met the inclusion criteria and were selected. Evidence revised indicates that supplementation with caffeine, β-alanine, sodium bicarbonate, creatine, and β-hydroxy-β-methylbutyrate has a positive effect on judo-related performance. Moreover, there is evidence suggesting that combining some of these nutritional supplements may produce an additive effect.

Time Course and Magnitude of Tolerance to the Ergogenic Effect of Caffeine on the Second Ventilatory Threshold

Pre-exercise caffeine ingestion has been shown to increase the workload at ventilatory threshold, suggesting an ergogenic effect of this stimulant on submaximal aerobic exercise. However, the time course of tolerance to the effect of caffeine on ventilatory threshold is unknown. This study aimed to determine the evolution of tolerance to the ergogenic effect of caffeine on the ventilatory threshold. Methods: Eleven participants (age 32.3 ± 4.9 yrs, height 171 ± 8 cm, body mass 66.6 ± 13.6 kg, VO2max = 48.0 ± 3.8 mL/kg/min) took part in a longitudinal, double-blind, placebo-controlled, randomized, crossover experimental design. Each participant took part in two identical treatments: in one treatment, participants ingested a capsule containing 3 mg of caffeine per kg of body mass per day (mg/kg/day) for twenty consecutive days; in the other treatment, participants ingested a capsule filled with a placebo for the same duration and frequency. During these treatments, participants performed a maximal ramp test on a cycle ergometer three times per week and the second ventilatory threshold (VT2) was assessed by using the ventilatory equivalents for oxygen and carbon dioxide. Results: A two-way ANOVA with repeated measures (substance × time) revealed statistically significant main effects of caffeine (p < 0.01) and time (p = 0.04) on the wattage obtained at VT2, although there was no interaction (p = 0.09). In comparison to the placebo, caffeine increased the workload at VT2 on days 1, 4, 6 and 15 of ingestion (p < 0.05). The size of the ergogenic effect of caffeine over the placebo on the workload at VT2 was progressively reduced with the duration of the treatment. In addition, there were main effects of caffeine (p = 0.03) and time (p = 0.16) on VO2 obtained at VT2, with no interaction (p = 0.49). Specifically, caffeine increased oxygen uptake at VT2 on days 1 and 4 (p < 0.05), with no other caffeine–placebo differences afterwards. For heart rate obtained at VT2, there was a main effect of substance (p < 0.01), while the overall effect of time (p = 0.13) and the interaction (p = 0.22) did not reach statistical significance. Heart rate at VT2 was higher with caffeine than with the placebo on days 1 and 4 (p < 0.05). The size of the effect of caffeine on VO2 and heart at VT2 tended to decline over time. Conclusion: Pre-exercise intake of 3 mg/kg/day of caffeine for twenty days enhanced the wattage obtained at VT2 during cycling ramp tests for ~15 days of ingestion, while there was a progressive attenuation of the size of the ergogenic effect of caffeine on this performance variable. Therefore, habituation to caffeine through daily ingestion may reduce the ergogenic effect of this stimulant on aerobic exercise of submaximal intensity.

REVIEW ON ERGOGENIC EFFECT OF WITHANIA SOMNIFERA (L.) DUNAL

Withania Somnifera (L.) Dunal is a commonly used herb in the alternative medical systems in the world. It is been investigated under several aspects of sports science due to athlete friendly benefits. The collective traits of performance enhancing consequence of an athlete can be described under the term ‘ergogenic ef-fect’. Though the herb is not been investigated as an ergogenic aid, the scattered scientific studies can pre-view its’ skill, strength, endurance and recovery promoting ability after competitions. The study was aimed to analyze its’ ergogenic effect using scientific evidences and classical Ayurveda references. Research data was collected from the online sources and classical Ayurveda references. Withania Somnifera found to be enhanced aerobic and anerobic exercise capacity, muscle strength, recovery process, anti-fatigue activity, endurance and immune-modulatory effect. Ayurveda literature also supports these evidences as it has been described as a Balya, Brimhana, Vatahara, Kaphahara and Shukrala herb. Correlation between these two concepts also suggests Withania Somnifera as an effective ergogenic aid.

Efectos de la suplementación con zumo de remolacha sobre la respuesta neuromuscular: revisión sistemática (Effect of beet juice supplementation (BJ) on neuromuscular response: a systematic review)

El zumo de remolacha (ZR) es una fuente nutricional rica en nitrato (NO3-) que, una vez ingerido, es reducido a óxido nítrico (ON). El ON posee efectos hipotensores, anti-inflamatorios y provoca mejoras en la eficiencia mitocondrial y en la regulación de la contractilidad muscular. Distintas investigaciones han comprobado que la suplementación con ZR presenta un efecto ergogénico en modalidades de resistencia cardiorrespiratoria y esfuerzos explosivos e intermitentes de alta intensidad. Sin embargo, dado que ninguna revisión ha valorado el efecto de la suplementación con ZR sobre la producción de fuerza muscular, el objetivo de la presente revisión sistemática es analizar el efecto de la suplementación con ZR sobre el rendimiento en la fuerza muscular. La búsqueda mediante palabras clave y conectores booleanos se realizó en las bases de datos Dialnet, Directory of Open Access Journals, Medline, Pubmed, Scielo, Scopus y SPORTDiscus. La estrategia de búsqueda empleada fue la siguiente: (nitrate OR beet*) AND (concepto 2) (supplement* OR nutr* OR diet*) AND (concepto 3) (strength OR "resistance exercise" OR "resistance training" OR "muscular power"). Tras la aplicación de los criterios de inclusión, un total de 14 artículos fueron seleccionados para la revisión. En la revisión se ha comprobado como la suplementación con ZR puede tener un efecto ergogénico sobre la producción de fuerza muscular bajo estimulación eléctrica, así como sobre la producción de potencia sobre contracciones isocinéticas únicamente a altas velocidades angulares, siendo el mecanismo explicativo una potenciación de la capacidad contráctil específicamente en las fibras musculares tipo II. Abstract. Beet juice (BJ) is a nutritional source rich in nitrate (NO3-) which, after ingestion, is reduced to nitric oxide (NO). NO has effects such as reduction in arterial pressure, anti-inflammatory effects, enhancement of mitochondrial efficiency, and regulation of muscle contractility. Different studies have reported that BJ supplementation has an ergogenic effect in modalities of cardiorespiratory endurance and explosive and intermittent high intensity efforts. Nevertheless, no review has assessed the effect of BJ supplementation on muscle strength production. Thus, the objective of this systematic review is to analyse the effect of BJ supplementation on muscle strength performance. The search using keywords and Boolean connectors was carried out in the databases Dialnet, Directory of Open Access Journals, Medline, Pubmed, Scielo, Scopus, and SPORTDiscus. The search strategy used was the following: (nitrate OR beet *) AND (concept 2) (supplement * OR nutr * OR diet *) AND (concept 3) (strength OR "resistance exercise" OR "resistance training" OR "muscular power "). After the application of the inclusion criteria, a total of 14 articles were selected for review. The review has shown how BJ supplementation can have an ergogenic effect on the production of muscle strength under electrical stimulation, as well as on the production of power over isokinetic contractions only at high angular speeds, the explanatory mechanism being a potentiation of the contractile capacity specifically in type II muscle fibers.

Bases de datos para Refining music tempo for an ergogenic effect on stationary cycling exercise

Aburto-Corona, J. & Aragón-Vargas, L.F. (2017). Refining music tempo for an ergogenic effect on stationary cycling exercise. Pensar en Movimiento: Revista de Ciencias del Ejercicio y la Salud, 15(2), 1-12. The effect of music on exercise performance has been studied from many perspectives, but the results have not been as clear as expected, probably due to a lack of appropriate controls. The purpose of this study was to measure stationary cycling performance in a warm environment under carefully controlled conditions, modifying only the presence of music and its tempo. Ten physically active students, 24.5±3.6 years (mean±SD) selected their favorite exercise music and performed a maximum cycling test. During subsequent visits to the laboratory, they pedaled at their preferred speed against a constant resistance (70% of maximum) in an environmentally controlled chamber (28.6±0.5 °C db and 65±3% rh) for 30 min, on three different days, without music (NM), medium tempo music (MT-120 bpm) or fast tempo music (FT-140 bpm), in random order. Perceived exertion (PE), heart rate (HR) and total work performed (W) were recorded. There was no significant difference among conditions for PE (4.47±1.52; 4.22±1.5; 3.83±2.06 a.u. for NM, MT and FT, respectively, p=.162) or HR (142.4±24.53; 142.6±24.37; 142.9±18.36 bpm for NM, MT and FT, respectively, p=.994), but W was different (43.4±19.02; 46.1±20.34; 47.1±20.97, kJ for NM, MT and FT, respectively, p=.009); post-hoc analysis showed that the W difference was only between FT and NM. Using individually selected preferred music in a carefully controlled environment, participants improved their spontaneous cycling performance only when the music had a fast tempo of 140 bpm.

Influence of Nitrate Supplementation on Endurance Cyclic Sports Performance: A Systematic Review

Endurance can be defined as the capacity to maintain one’s velocity or power output for the longest possible time. Maintaining such activity can lead to the onset of fatigue. Dietary nitrate supplementation produces an ergogenic effect due to the improvement of mitochondrial oxygen efficiency through a reduction in the oxygen cost of exercise that increases vasodilation and blood flow to the skeletal muscle in recreationally active subjects. However, the effects of dietary nitrate supplementation on well-trained endurance athletes remain unclear; such supplementation could affect more performance areas. In the present study, a systematic review of the literature was conducted to clarify the use and effects of nitrate as a dietary supplement in endurance athletes trained in cyclic sports (repetitive movement sports). A systematic search was carried out following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines in the databases of SCOPUS, Web of Science (WOS), Medline (PubMed), and Sport Discus from 1 January 2010 to 30 November 2019. Twenty-seven studies were included in the study. The methodological quality of the articles was assessed using the McMaster Critical Review Form. Statistically significant ergogenic results were obtained in 8 (29.63%) of the 27 studies investigated, with significant results obtained for cardiorespiratory parameters and performance measures. Improvement in exercise tolerance was obtained, which could help with exhaustion over time, while the improvement in exercise economics was not as clear. Additionally, the dose necessary for this ergogenic effect seems to have a direct relationship with the physical condition of the athlete. The acute dose is around 6–12.4 mmol/day of nitrate administered 2–3 h before the activity, with the same amount given as a chronic dose over 6–15 days. Further studies are required to understand the factors that affect the potential ergogenic impacts of nitrate on athletic performance among endurance athletes.