Search Results (572)

Objectives: High-intensity interval training (HIIT) has become an increasingly popular conditioning strategy in women’s basketball due to its effectiveness in improving physical performance. The aim of this study was to examine the effects of a six-week HIIT on combined aerobic and anaerobic capacity, running speed, agility, repeated sprint ability, and explosive power in elite female basketball players. Methods: Thirty elite female basketball players (21.81 ± 2.12 years) were randomly assigned to either a HIIT group (n = 15) or a control group (n = 15). Results: Pre- and post-intervention assessments included running speed (0–20 m); the 5–0–5, Zig-zag, and Pro-agility tests; vertical jump performance (CMJ, CMJA, and SJ); repeated sprint ability (RSA); aerobic capacity assessed by the 30–15 Intermittent Fitness Test; and VO₂max. Statistically significant Group × Time interaction effects emerged for running speed (5 m, 10 m, and 20 m), aerobic capacity (30–15 IFT and VO₂max), and Zig-zag agility performance (p < 0.05), indicating greater improvements in the HIIT group compared with the control group. Significant main effects of time were observed for RSA and vertical jump performance, indicating improvements in both groups; however, no significant Group × Time interactions were found. Conclusions: These findings suggest that a six-week HIIT is an effective and time-efficient conditioning strategy for enhancing aerobic capacity, sprint performance, and change-of-direction ability in elite female basketball players. Full article

The article presents an energy, economic and environmental (3-E) analysis of a reference wastewater treatment plant (WWTP) with a capacity of 200,000 population equivalent (PE). The analysis includes sewage sludge treatment, anaerobic digestion (AD), combined heat and power (CHP), and mono-incineration of solar-dried sludge. The specific investment cost for the reference WWTP is 435 €/PE. Annual costs for operation and maintenance are estimated at 26 €/(PE·y) and the energy costs are 5 €/(PE·y). The annual energy demands are 32 kWh_el/(PE·y) of electricity and 14 kWh_th/(PE·y) of thermal energy for digesters’ heating. For a specific sludge quantity of 20 kg_DS/(PE·year), the biogas production is 245 Nm³/t_DS or 5 m³/(PE·y). Biogas-driven CHP supplies 10.3 kWh/(PE·year) of electricity and 14.7 kWh/(PE·year) of thermal energy, which meets 30% of the electrical demand and 100% of the thermal energy demand. Total (capital and operation) costs of sludge mono-incineration are evaluated at 300 €/t_DM or 6 €/PE. The heating value of digested and solar-dried sludge is 2 kWh/kg_WM. The total cost of the solar drying system is 30 €/PE while the sludge solar drying rate is 370 kg_DM/(m²·y). The environmental analysis showed that the on-site carbon footprint of the reference WWTP is 50 kg_CO2eq/(PE·y), with the largest contributions arising from N₂O emissions during wastewater treatment, CO₂ from sludge mono-incineration, and CO₂ from biogas combustion in the CHP unit. Full article

Background: Paralympic powerlifting requires high upper-limb force production within a short time frame, making anaerobic power a potentially relevant physiological component associated with competitive performance. This study aimed to analyze the associations between biodynamic variables and competitive performance in Paralympic powerlifting athletes. Methods: A cross-sectional study was conducted with 13 elite Paralympic powerlifters. Body composition was assessed using DXA. Arm isometric strength was measured by the handgrip test, dynamic strength by the medicine ball throw, and anaerobic power by an upper-limb-adapted Wingate test. Competitive performance was determined based on the official ranking position in the Brazilian Paralympic Powerlifting Championship. Results: Significant correlations were observed between all anaerobic power variables and competitive performance: relative mean power (r = −0.864; p < 0.001), mean power (r = −0.804; p = 0.003), relative peak power (r = −0.766; p = 0.006), and peak power (r = −0.791; p = 0.004). Additionally, total lean mass and left-hand grip strength showed significant associations with maximum competition lift in exploratory linear regression analyses. Conclusions: Upper-limb anaerobic power showed strong associations with competitive performance indicators in Paralympic powerlifting athletes. Furthermore, lean mass and upper-limb isometric strength showed significant associations with maximum competition lift, supporting the multifactorial nature of competitive performance in Paralympic powerlifting. These findings suggest the potential relevance of integrating power-, strength-, and body composition-oriented assessments and interventions into the training process of elite Paralympic powerlifters. Full article

Objectives: Local positioning systems (LPSs) used in indoor team sports generate a large number of external load variables, often exceeding practical monitoring capacity. The redundancy and overlap among these variables make it difficult to identify the most informative metrics for performance analysis and load management. This study aimed to reduce the dimensionality of external load variables derived from LPS data and to identify data-driven external-load observation profiles using principal component analysis and clustering techniques. Methods: A total of 188 observations from indoor team sports (basketball, handball, and futsal) were analyzed. Continuous external load variables were standardized and subjected to principal component analysis (PCA), with component retention based on a ≥90% cumulative explained variance threshold. K-means clustering was applied in both the full standardized feature space and the PCA-reduced space. The optimal number of clusters was determined using silhouette analysis and the elbow method. Agreement between clustering solutions was assessed using Adjusted Rand Index (ARI) and Normalized Mutual Information (NMI). Cluster characteristics were further examined using descriptive statistics and variable separation analysis. Results: The first two principal components explained 53.7% of the total variance, representing high-intensity external load and neuromuscular load dimensions, while 12 components were required to exceed 90% cumulative explained variance. Clustering analysis consistently identified three moderately separated clusters in both the full and PCA-reduced spaces. The PCA-based solution demonstrated improved separation (silhouette = 0.362) compared to the full-space solution (silhouette = 0.319). Agreement between clustering approaches was high (ARI = 0.981; NMI = 0.971), indicating that dimensionality reduction largely preserved the main clustering structure within the analyzed dataset. The most discriminative variables included jump load, acceleration load, metabolic power, and anaerobic activity distance. Conclusions: A large set of external load variables can be reduced into interpretable latent dimensions that support exploratory external-load profile identification. The combination of PCA and clustering provides an exploratory and structure-preserving framework for summarizing complex external-load datasets and identifying latent load dimensions. These findings may assist future monitoring strategies; however, the practical utility of the identified profiles requires prospective validation before implementation in training-load management. Full article

This study presents an integrated optimization framework for enhancing biogas and methane production through anaerobic digestion, addressing the challenge of identifying optimal operating conditions across multiple interacting parameters. Biochemical methane potential tests were conducted to evaluate the individual effects of four critical operational parameters: temperature, mixing regime, inoculum-to-substrate (I-S) ratio, and chemical oxygen demand load (COD-L). Experimental findings confirmed that thermophilic conditions, mixing once a day, I-S ratio of 1:2, and moderate COD loading consistently delivered the most favorable biogas and methane yields. Kinetic modeling, including the Modified Gompertz and Logistic models, showed strong predictive agreement with experimental data (R² > 0.90), reliably capturing production dynamics across all tested conditions. Polynomial response surface methodology further identified COD-L as the dominant driver of methane yield, with optimal operating conditions falling within moderate temperature and COD-L ranges. This revealed significant nonlinear interactions between parameters. Building on these findings, the Crayfish Optimization algorithm successfully determined global optimal conditions, achieving a maximum biogas production of 0.371 Nm³/kg.VS. These results highlight how combining experimental investigation with predictive modeling and metaheuristic optimization creates a powerful decision-support framework for improving the efficiency and stability of anaerobic digestion systems. Full article

Background: New Zealand blackcurrant (NZBC) is an anthocyanin-rich supplement with reported ergogenic effects in endurance exercise; however, its effects in resistance-trained adults remain largely unexplored. Objective: This study aimed to examine whether seven days of low- or high-dose NZBC supplementation improves resistance exercise performance, anaerobic capacity, and cognitive function in resistance-trained adults. Methods: Twenty resistance-trained adults completed a randomized, double-blind, placebo-controlled crossover trial with four conditions: no-capsule control (CON), placebo (PL), low-dose blackcurrant (LDBC; 250 mg·day⁻¹), and high-dose blackcurrant (HDBC; 600 mg·day⁻¹), each for seven days. Outcomes included bench press and leg press 1RM, total lifting volume, Tendo-derived bench press power, 30 s Wingate performance, Stroop Color–Word Test scores, readiness, perceived exertion, hemodynamic responses, and adverse events. Results: LDBC and HDBC increased bench press 1RM versus CON and PL, with increases versus CON of +3.33 kg (ES = 0.72; p = 0.005) and +2.34 kg (ES = 0.49; p = 0.041), respectively. Leg press 1RM was higher in PL, LDBC, and HDBC versus CON, with the largest effects observed for LDBC (+37.2 kg, ES = 1.33; p < 0.001) and HDBC (+25.8 kg, ES = 1.11; p < 0.001). Leg press total lifting volume was substantially higher with LDBC (+2627 kg, ES = 1.56; p < 0.001) and HDBC (+1025 kg, ES = 0.74; p = 0.004) versus CON. Bench press volume showed no significant overall treatment effect (p > 0.05). For Tendo-derived power, HDBC exceeded PL for peak (+79.5 W; p = 0.006) and mean power (+46.2 W; p = 0.026). Wingate outcomes did not differ across conditions (all p > 0.05). LDBC exceeded PL on Stroop Color, Color–Word, and total scores (all p < 0.05); HDBC exceeded PL on Color–Word only. Hemodynamic responses and adverse events were comparable across all conditions. Conclusions: Short-term NZBC supplementation improved selected resistance-exercise and cognitive outcomes, with the strongest evidence observed for outcomes that exceeded both CON and PL. The PL response relative to CON suggests that non-specific capsule, expectancy, repeated testing, or period effects may have contributed to some of the lower-body improvements; therefore, placebo-controlled contrasts should be emphasized when interpreting NZBC-specific efficacy. Wingate performance was unaffected, and both doses were well tolerated over the short-term supplementation period. Full article

Background: Citrulline malate (CM) is commonly used as an ergogenic supplement, but its effects on exercise performance and perceived exertion remain uncertain. This systematic review and meta-analysis evaluated the effects of CM supplementation, with attention paid to differences between acute and chronic protocols. Methods: Six databases were searched from inception to August 2025. Randomized controlled trials examining CM supplementation on exercise performance and/or perceived exertion were included. Hedges’ g was synthesized using three-level random-effects models to account for dependent effect sizes. Subgroup and moderator analyses explored supplementation protocol, exercise modality, sex, training status, dosage, and ingestion timing. Risk of bias, small-study effects, sensitivity analyses, and GRADE certainty were assessed. Results: Thirty randomized controlled trials contributed 138 effect sizes from 644 participants. CM supplementation was associated with a small improvement in overall exercise performance (g = 0.16, p = 0.01); however, prediction intervals were wide and statistical power was limited. The pooled effect on perceived exertion was not statistically significant. Current evidence appeared more stable for acute than chronic supplementation, although the protocol subgroup difference remained uncertain. Among acute studies, exploratory subgroup analyses suggested possible benefits for aerobic endurance and short anaerobic tasks, but these findings were not robust across sensitivity analyses. No significant between-subgroup differences were found for sex, training status, dosage, or ingestion timing. GRADE certainty ranged from low to very low. Conclusions: CM supplementation may be associated with small, context-dependent improvements in exercise performance, but current evidence remains limited and uncertain. Reliable dosing, timing, and target populations have not been established. Larger trials with verified supplement composition and standardized protocols are needed. Full article

Anaerobic digestion is a viable pathway to mitigate environmental impacts from swine manure in tropical regions while contributing to circular economy strategies. However, no standardized or integrated framework currently exists that simultaneously quantifies the closure of energy, material, carbon, nutrient, and water loops at the farm scale. This research presents the techno-economic design and environmental assessment of a covered, mechanically agitated lagoon biodigester for a 10,000-head swine fattening module located in Matanzas, Cuba. The system is sized by integrating hydraulic, thermal, and structural parameters, and its economic viability is assessed through Net Present Value (NPV = $1.09 million), Internal Rate of Return (IRR = 32%), and a payback period of approximately three years. A comparative screening-level life cycle assessment shows that biogas-based electricity generation substantially reduces impacts on climate change, air quality, and fossil fuel scarcity compared with conventional diesel-based generation, with trade-offs in eutrophication and ecotoxicity. As a key methodological contribution, five quantitative circular economy indicators are proposed and calculated: the Energy Self-Sufficiency Ratio (ESSR = 1.71), the Waste Valorization Index (WVI = 0.91), the Decarbonization Index (DCI = 6.7), the Fertilizer Substitution Rate (FSR = 16.3 t N year⁻¹), and the Water Closure Factor (WCF = 1.30). These indicators show that the system achieves a 71% net energy surplus, valorizes over 90% of the input mass, avoids 6.7 times more emissions than it generates, replaces synthetic fertilizers, and returns more water than it consumes. The findings provide quantitative evidence that the convergence of mesophilic operation without auxiliary heating, high carbon intensity of the power grid, and availability of agricultural land enhances circularity performance in tropical covered lagoon bioreactors, and the proposed integrated indicator framework, aligned with ISO 59020:2024, provides a reproducible and transferable methodological basis for the comparative assessment of anaerobic digestion systems for livestock waste. Full article

The increasing worldwide demand for sustainable energy and effective waste management has heightened interest in solutions. Microbial fuel cells (MFCs) represent a potential category of bioelectrochemical systems that directly transform the chemical energy contained in organic waste into electrical energy via the metabolic processes of electroactive microorganisms. In the last twenty years, significant advancements have occurred in the comprehension of extracellular electron transfer (EET) mechanisms, biofilm formation, microbial community dynamics, electrode material engineering, and reactor design, resulting in marked enhancements in power density and wastewater treatment efficacy. Despite these breakthroughs, the extensive deployment and commercialization of MFC technology are constrained by various hurdles, including inadequate energy recovery, elevated material and fabrication expenses, operational instability, and the intricacies of system scale-up. This cutting-edge analysis offers a thorough evaluation of recent advancements in MFCs and their incorporation with sophisticated technology for waste management and energy generation. Focus is directed towards essential bioelectrochemical principles, microbial and biofilm engineering techniques, sophisticated electrode and membrane materials, reactor designs, and hybrid MFC systems integrated with anaerobic digestion, microbial electrolysis, and advanced oxidation methods. Ultimately, emerging trends, significant knowledge deficiencies, and future research goals are defined to inform the advancement of next-generation MFC systems that support circular economy and net-zero energy initiatives. Full article

Background: Lower-limb performance is commonly assessed using maximal strength, isokinetic, jump, and anaerobic power tests, but whether these assessments provide overlapping or complementary information in healthy young adults without recent regular resistance training remains unclear. Methods: This exploratory cross-sectional secondary analysis examined associations among lower-limb maximal strength, selected isokinetic knee-extension variables, countermovement jump (CMJ) flight time, and 6 s Wingate peak power in 30 healthy male university students. Maximal dynamic strength was assessed using one-repetition maximum (1RM) tests for leg press, leg extension, and leg curl. Isokinetic knee function was evaluated using 60°/s knee extension peak torque and 180°/s knee extension total work. Pearson correlations, body-mass-adjusted partial correlations, and exploratory regression models were performed. Results: Leg press 1RM was strongly correlated with 6 s Wingate peak power, but not with CMJ flight time, in the zero-order analysis. After body-mass adjustment, leg press 1RM was associated with both outcomes. In exploratory regression models, leg press 1RM showed the most consistent associations, whereas the selected isokinetic variables showed less consistent relationships. Conclusions: In this exploratory sample, leg press 1RM showed the most consistent associations with the two performance outcomes examined, particularly 6 s Wingate peak power. The selected isokinetic knee-extension variables appeared to provide more joint-specific information. These findings should be interpreted as sample-specific associations, not as evidence that one test can predict or replace another. Full article

This systematic review aimed to evaluate the tests used to assess neuromuscular performance in adult female basketball players and to provide evidence-based recommendations for practice and future research. Following PRISMA guidelines and registered in PROSPERO (CRD42025638889), four databases were systematically searched from inception to April 2026. A total of 62 studies were included in the qualitative synthesis and 39 in the quantitative analysis. The most frequently reported assessments examined anthropometry, muscular power, linear speed, change-of-direction (COD) performance, strength, anaerobic capacity, and aerobic capacity. However, substantial variability was observed in testing protocols, outcome variables, and reporting methods. Across studies, performance outcomes showed considerable overlap between competition levels, suggesting that competitive standard alone is not a reliable indicator of neuromuscular performance. Differences in anthropometric characteristics and physical performance were largely influenced by playing position and contextual factors. A key finding was the predominant reliance on outcome-based metrics (e.g., jump height, sprint time), with limited use of force–time variables that provide deeper insight into neuromuscular function. In addition, important methodological limitations were identified, including inconsistent testing procedures, lack of standardized reporting, and the absence of female-specific considerations such as menstrual cycle status. To address these limitations, this review proposes a practical testing framework that integrates reliable, sport-specific, and time-efficient assessment methods. Future research should prioritize the implementation of standardized protocols, the inclusion of force–time analysis, and the development of large-scale descriptive datasets specific to female basketball players. These advances are essential to improve performance monitoring, optimize training prescription, and enhance injury risk management in this population. Full article

A livestock farm in southern Taiwan produces wastewater with high concentrations of nitrogen and organics, which inhibit anaerobic methanogens and limit the efficiency of its biogas system. To enhance energy recovery, this study developed a liter-scale microbial fuel cell (MFC) system aimed at harvesting electricity from livestock wastewater, serving as a supplementary energy recovery pathway alongside the biogas process. According to the five analyses, the chemical oxygen demand (COD) of raw wastewater ranged from 14 to 21 g L⁻¹, with acetate concentrations ranging between 40 and 112 mM. Propionate and butyrate were consistently below 32 mM and 18 mM, respectively. Ammonium ranged from 1.1 to 1.7 g-N L⁻¹, indicating the wastewater’s high organic load and elevated nitrogen content. Two liter-scale MFCs, ch5 and ch7, were operated for over 70 d. From days 7 to 28, both MFCs employed a fill-and-draw mode, achieving optimal COD removal exceeding 80%. After resolving leakage issues between days 30 and 40, the system was restarted on day 40, yielding 76% (ch5) and 82% (ch7) of COD removal. Continuous operation began on day 59, and both reactors maintained COD removal rates above 80% for most of the subsequent two-week period. The best power outputs for ch5 and ch7 reached 1.11 and 0.82 W m⁻³, respectively. Although both liter-scale reactors achieved COD removal and measurable power output, the most important finding was obtained from the inoculum comparison experiments. After 54 days of acclimating to raw wastewater solids, no significant current was observed. In contrast, digestate solids acclimated with carbon powder for 22 d produced a peak current of 42.5 A m⁻³ at 147 h, with COD removal rates of 67–73% and complete removal of organic acids. The key conclusion of this study is that anaerobic digestate exhibits electroactive microbial potential, whether operated in liter-scale reactors or acclimated with carbon powder. Further investigation into the microbial community structure is warranted to optimize system performance. Full article

Introduction: Vitamin B12 (VB12), particularly its active form methylcobalamin (MeB12), contributes to neuromuscular function and energy metabolism, which may be relevant for sports performance. However, evidence on the acute effects of MeB12 supplementation in athletes remains limited. Objective: To evaluate the effects of short-term (3-day) MeB12 supplementation on anaerobic and cognitive performance in amateur cyclists. Methods: A randomized, triple-blind, placebo-controlled crossover clinical trial was conducted in 18 amateur cyclists. Participants received formulations containing MeB12 (1 mg/day; MecobalActive^®, HTBA, Murcia, Spain) or placebo for three consecutive days. Anaerobic performance was assessed using a repeated Wingate protocol, and cognitive performance was evaluated using a light-based mental agility/reaction test system. Biochemical analyses included serum VB12 concentrations. Primary outcomes included peak power output (absolute and relative), fatigue index across repeated sprints, and cognitive response time. Results: Compared with placebo, MeB12 supplementation was associated with higher peak power output, with increases in absolute maximal power (PMAX: +4.1%, p = 0.016) and relative maximal power (PMAXREL: +4.4%, p = 0.013). MeB12 supplementation was associated with a smaller decline in performance across repeated sprints, with a smaller drop in fatigue index from the first to the fifth sprint (p = 0.012). Pre-exercise cognitive performance improved, with a shorter total reaction test time (−4.9%, p < 0.001) versus placebo. Serum VB12 concentrations increased by 16.8% following MeB12 supplementation. Conclusions: A brief, 3-day intervention with methylcobalamin (1 mg/day) was associated with positive changes, when compared with placebo, in selected markers of anaerobic performance (peak power and fatigue-related decline) and pre-exercise cognitive performance in recreationally trained amateur cyclists, suggesting a possible involvement of peripheral and central mechanisms. Full article

Introduction: Vertical jump performance is linked to key performance indicators in rugby, including tackling success and ruck involvement. Although plyometric jump training (PJT) is known to enhance explosive qualities in various sports, its specific effects in rugby remain unclear. Objective: To synthesise evidence on the effects of PJT on vertical jump ability and other physical fitness components in adult rugby players. Methods: A systematic review was conducted in accordance with PRISMA 2020 guidelines. PubMed, EBSCO (SPORTDiscus), WoS, and Scopus were searched up to December 2025. Experimental and quasi-experimental studies involving rugby players undertaking PJT programmes of at least two weeks, with at least one vertical jump outcome, were included. Two reviewers independently performed study selection and data extraction. Risk of bias was assessed using the RoB 2.0 tool. Results: Seven studies involving 178 male players were included. PJT improved sprint speed, change of direction, anaerobic power, reactive strength, lower-limb stiffness, and isometric plantar flexion strength. Gains in countermovement jump power were noted in some conditions, such as training on softer surfaces. However, improvements in jump height were inconsistent. Conclusion: PJT enhances several important physical qualities in rugby players but shows variable effects on vertical jump height. Further high-quality research is needed. Full article

Background/Objectives: Low-carbohydrate (LCD) and ketogenic diets (KD) are increasingly adopted by athletes due to their ability to enhance fat oxidation and induce metabolic adaptations. While their effects on aerobic power and capacity have been widely investigated, their influence on anaerobic performance remains unclear. Given the strong dependence of high-intensity exercise on glycolytic metabolism and muscle glycogen availability, carbohydrate restriction may have significant implications for short-duration maximal efforts and repeated high-intensity exercise. Therefore, this systematic review and meta-analysis aimed to evaluate the effects of LCD and KD on anaerobic performance outcomes in trained athletes. Methods: A comprehensive search of five electronic databases (PubMed, SCOPUS, Web of Science, SPORTDiscus, and Cochrane Central Register of Controlled Trials) identified 13 unique studies (yielding 15 study-level entries across three anaerobic performance domains) meeting comprehensive inclusion criteria. Individual study sample sizes ranged from n = 5 to n = 65 participants, reflecting substantial inter-study variability that should be considered when interpreting pooled estimates. Outcomes included peak and mean power output, repeated sprint performance, blood lactate responses, and markers of substrate utilization. Study quality was assessed using the Newcastle–Ottawa Scale, and meta-analyses were performed using random-effects models where appropriate. Results: Overall, the effects of carbohydrate-restricted diets on anaerobic performance were domain-specific. Some studies reported maintained or slightly improved peak power during single maximal efforts, while others showed no effect. Impairments were more consistently observed in repeated high-intensity exercise. Repeated sprint performance was impaired in several studies, likely reflecting reduced muscle glycogen availability and limited glycolytic ATP production. Carbohydrate restriction consistently increased fat oxidation and was associated with lower blood lactate concentrations during high-intensity exercise. Random-effects meta-analyses yielded domain-specific pooled effect sizes: maintained-to-slightly-improved anaerobic power output (Cohen’s d = +0.29; 95% CI: −0.08 to +0.66), modestly impaired repeated sprint ability (d = −0.33; 95% CI: −0.80 to +0.14), and a large, consistent reduction in blood lactate concentration (d = −0.89; 95% CI: −1.20 to −0.58). Given substantial between-study heterogeneity in intervention durations (2 days to 12 weeks), dietary composition, athlete populations, and outcome measures (1RM, Wingate, CMJ within the power domain; varied protocols within the RSA and lactate domains), these pooled estimates should be interpreted as exploratory rather than confirmatory. Conclusions: LCD and KD appear to have domain-specific effects on anaerobic performance in trained athletes. Although single, short-duration efforts may be preserved in some contexts, repeated, high-intensity performance appears to be more susceptible to impairment. These findings highlight the importance of aligning dietary strategies with the metabolic demands of training and competition. Full article