Feasibility of the 2-point method to determine the load-velocity relationship variables during the countermovement jump exercise

Purpose: This study aimed to examine the reliability and validity of load−velocity (L–V) relationship variables obtained through the 2-point method using different load combinations and velocity variables. Methods: Twenty men performed 2 identical sessions consisting of 2 countermovement jumps against 4 external loads (20 kg, 40 kg, 60 kg, and 80 kg) and a heavy squat against a load linked to a mean velocity (MV) of 0.55 m/s (load0.55). The L–V relationship variables (load-axis intercept (L0), velocity-axis intercept (v0), and area under the L–V relationship line (Aline)) were obtained using 3 velocity variables (MV, mean propulsive velocity (MPV), and peak velocity) by the multiple-point method including (20–40–60–80–load0.55) and excluding (20–40–60–80) the heavy squat, as well as from their respective 2-point methods (20–load0.55 and 20–80). Results: The L–V relationship variables were obtained with an acceptable reliability (coefficient of variation (CV) ≤ 7.30%; intra-class correlation coefficient ≥ 0.63). The reliability of L0 and v0 was comparable for both methods (CVratio (calculated as higher value/lower value): 1.11–1.12), but the multiple-point method provided Aline with a greater reliability (CVratio = 1.26). The use of a heavy squat provided the L–V relationship variables with a comparable or higher reliability than the use of a heavy countermovement jump load (CVratio: 1.06–1.19). The peak velocity provided the load–velocity relationship variables with the greatest reliability (CVratio: 1.15–1.86) followed by the MV (CVratio: 1.07–1.18), and finally the MPV. The 2-point methods only revealed an acceptable validity for the MV and MPV (effect size ≤ 0.19; Pearson's product-moment correlation coefficient ≥ 0.96; Lin's concordance correlation coefficient ≥ 0.94). Conclusion: The 2-point method obtained from a heavy squat load and MV or MPV is a quick, safe, and reliable procedure to evaluate the lower-body maximal neuromuscular capacities through the L–V relationship

Self-Selected Versus Standardised Warm-Ups; Physiological Response on 500 m Sprint Kayak Performance

This study investigated the effectiveness of a self-selected (SS) warm-up on 500 m sprint kayak performance (K500) compared to continuous (CON) and intermittent high intensity (INT)-type warm-ups. Twelve nationally ranked sprint kayakers (age 17.7 ± 2.3 years, mass 69.2 ± 10.8 kg) performed CON (15 min at the power at 2 m·mol−1), INT (10 min at 2 m·mol−1, followed by 5 × 10 s sprints at 200% power at VO2max with 50 s recovery at 55% power at VO2max), and SS (athlete’s normal competition warm-up) warm-ups in a randomised order. After a five-minute passive recovery, K500 performance was determined on a kayak ergometer. Heart rate and blood lactate (BLa) were recorded before and immediately after each warm-up and K500 performance. Ratings of perceived exertion (RPE) were recorded at the end of the warm-up and K500. BLa, heart rate, and RPE were generally higher after the INT than CON and SS warm-ups (p 0.05). RPE and changes in BLa and heart rate after the K500 were comparable. There were no differences in K500 performance after the CON, SS, or INT warm-ups. Applied practitioners can, therefore, attain similar performance independent of warm-up type

Effects of small-sided games vs. conventional endurance training on endurance performance in male youth soccer players: A meta-analytical comparison

Background: Small-sided games have been suggested as a viable alternative to conventional endurance training to enhance endurance performance in youth soccer players. This has important implications for long-term athlete development because it suggests that players can increase aerobic endurance through activities that closely resemble their sport of choice. Objectives: The objectives of this meta-analysis were to compare male youth soccer players’ adaptability to small-sided games vs. conventional endurance training and to establish exercise prescription guidelines for this population. Data Sources: The data sources utilised were Google Scholar, PubMed and Microsoft Academic. Study Eligibility Criteria: Studies were eligible for inclusion if interventions were carried out in male soccer players (aged 3 min. Study Appraisal and Synthesis Methods: The inverse-variance random-effects model for meta-analyses was used because it allocates a proportionate weight to trials based on the size of their individual standard errors and facilitates analysis whilst accounting for heterogeneity across studies. Effect sizes were represented by the standardised mean difference and presented alongside 95% confidence intervals. Results: Seven studies were included in this meta-analysis. Both modes of training were effective in increasing endurance performance. Within-mode effect sizes were both of moderate magnitude [small-sided games: 0.82 (95% confidence interval 0.05, 1.60), Z = 2.07 (p = 0.04); conventional endurance training: 0.89 (95% confidence interval 0.06, 1.72), Z = 2.10 (p = 0.04)]. There were only trivial differences [0.04 (95% confidence interval − 0.36, 0.43), Z = 0.18 (p = 0.86)] between the effects on aerobic endurance performance of small-sided games and conventional endurance training. Subgroup analyses showed mostly trivial differences between the training methods across key programming variables such as set duration (≥ or < 4 min) and recovery period between sets (≥ or < 3 min). Programmes that were longer than 8 weeks favoured small-sided games [effect size = 0.45 (95% confidence interval − 0.12, 1.02), Z = 1.54 (p = 0.12)], with the opposite being true for conventional endurance training [effect size = − 0.33 (95% confidence interval − 0.79, 0.14), Z = 1.39 (p = 0.16)]. Programmes with more than 4 sets per session favoured small-sided games [effect size = 0.53 (95% confidence interval − 0.52, 1.58), Z = 0.98 (p = 0.33)] with only a trivial difference between those with 4, or fewer, sets [effect size = − 0.13 (95% confidence interval − 0.52, 0.26), Z = 0.65 (p = 0.52)]. Conclusions: Small-sided games are as effective as conventional endurance training for increasing aerobic endurance performance in male youth soccer players. This is important for practitioners as it means that small-sided games can allow both endurance and skills training to be carried out simultaneously, thus providing a more efficient training stimulus. Small-sided games offer the same benefits as conventional endurance training with two sessions per week, with ≥ 4 sets of 4 min of activity, interspersed with recovery periods of 3 min, recommended in this population

Expressão da esterilidade feminina e da carpeloidia em mamoeiro sob diferentes ambientes de cultivo protegido.

O presente estudo teve por objetivo avaliar a ocorrência de esterilidade feminina e de carpeloidia em mamoeiros hermafroditas 'Baixinho-de-Santa Amália' cultivados sob manejo orgânico, em diferentes tipos de ambiente de proteção,e conduzido com ou sem bifurcação do tronco no transcorrer das quatro estações do ano. Foram construídos três tipos de estruturas de proteção contíguas: (i) estufa (cobertura de plástico); (ii) estufa sombreada (cobertura adicional de tela 'sombrite' - 30% sobre o plástico), e (iii) telado (cobertura exclusiva de tela 'sombrite' - 30%), ao lado de uma área de ambiente natural, a pleno sol. Nestes locais, foram cultivados, dentro das normas técnicas da agricultura orgânica, mamoeiros da cv. Baixinho-de-Santa-Amália. Em metade das plantas, abrangendo todos os ambientes de cultivo, a gema apical foi incisada, logo após a sexagem, visando à bifurcação do tronco. Para efeito de análise de variância, foram considerados quatro blocos por ambiente de cultivo, tendo cada bloco três repetições relativas ao modo de condução das plantas (com e sem bifurcação do tronco). Para análise estatística, procedeu-se à "análise conjunta de experimentos", no caso, os ambientes de cultivo. Nos mamoeiros com tronco bifurcado, houve diminuição do número de frutos carpeloides e aumento do número de flores fêmeas estéreis. No entanto, essa bifurcação não influenciou a frequência de frutos normais. Durante a primavera (setembro a dezembro), e notadamente na estufa, o maior número de frutos carpeloides por planta correlacionou-se a temperaturas mais elevadas, maior amplitude térmica e maior vigor vegetativo; já, a maior ocorrência de flores estaminadas correlacionou-se também a temperaturas elevadas, baixa luminosidade e menor vigor vegetativo. Por outro lado, essas mesmas condições ambientais e fenológicas favoráveis à carpeloidia aumentaram a quantidade de frutos normais, assim contribuindo positivamente para a produtividade do mamoeiro

Neurological disorders in pregnant women in low- and middle-income countries - Management gaps, impacts, and future prospects: A review perspective

Neurological disorders during pregnancy are a substantial threat to women’s health, particularly in low- and middleincome countries. Furthermore, a critical shortage of mental health workers and neurologists exacerbates the already pressing issue, where a lack of coordination of respective healthcare among multidisciplinary teams involved in managing these conditions perpetuates the current state of affairs. Financial restrictions and societal stigmas associated with neurological disorders in pregnancy amplify the situation. Addressing these difficulties would necessitate a multifaceted approach comprising investments in healthcare infrastructure, healthcare professional education and training, increased government support for research, and the implementation of innovative care models. Improving access to specialized treatment and coordinated management of antenatal neurological diseases will precipitate improved health outcomes for women and their families in low- and middle-income countries

Results from the CUORE-0 experiment

The CUORE-0 experiment searched for neutrinoless double beta decay in 130Te using an array of 52 tellurium dioxide crystals, operated as bolometers at a temperature of 10 mK. It took data in the Gran Sasso National Laboratory (Italy) since March 2013 to March 2015. We present the results of a search for neutrinoless double beta decay in 9.8 kg-years 130Te exposure that allowed us to set the most stringent limit to date on this half-life. The performance of the detector in terms of background and energy resolution is also reported