The impact of concurrent training in team sports and soccer

Team sports players are frequently required to integrate multiple physical components, including strength and endurance capacity, to maximize their performance during both training and competitions. The combination of strength and endurance within a periodized program is known as concurrent training. Recently, concurrent training has emerged as an innovative method to enhance both muscular strength and aerobic performance, tailored to the specific requirements and diverse nature of each sport. However, concurrent training may induce excessive fatigue and compromise performance potentiation, depending on training prescription parameters. This distinction between the interference effect and performance enhancement presents a complex challenge for any team sports system. Consequently, the objective of this review was to scrutinize the efficacy, practical application, and methodological aspects of concurrent training. Additionally, it aims to elucidate strategies to mitigate the complexities associated with the interference effect, thereby optimizing the benefits of concurrent training modality for team sports, emphasizing soccer. The major findings indicate that concurrent training can improve strength and endurance qualities in athletes, but under certain conditions, it can also interfere with adaptations. Appropriate programming strategies, such as proper sequencing, scheduling, volume, intensity, and recovery, can help mitigate these negative effects. Additionally, whereas more experienced athletes display greater proficiency in executing concurrent training programs, younger players, particularly those under 14, tend to experience minimal interference effects from this training approach, making it well-suited for their development. Overall, concurrent training has been demonstrated as an effective and efficient method for improving strength and endurance performance in team sports players.

Effects of 34 Weeks of Military Service on Body Composition and Physical Fitness in Military Cadets of Angola

Military personnel need physical fitness to effectively carry out operational military activities within their specific field of operation. This research investigates the effects of a 34-week training program on Angolan cadets' body composition, muscle strength, and cardiorespiratory fitness. Seventy-four volunteer recruits, aged 18 to 26 years, were monitored during their eight-month military service, following an exercise program protocol comprising 12 weeks of strength training followed by 24 weeks of endurance training. Anthropometric variables, including body mass, body mass index, and fat mass, were assessed, along with cardiorespiratory fitness (VO2max), sprint performance, countermovement jump (CMJ), medicine ball throw, push-ups, and curl-ups. The physical training protocol encompassed running sessions, strength exercises, agility drills, and flexibility exercises. The initial assessment revealed gender differences in various parameters such as body mass, body fat percentage, VO2max, sprinting, countermovement jump (CMJ), medicine ball throw, and push-ups. Following the training program, changes were observed in all variables (effect size between 0.48 and 2.33, p < 0.01) for the participants. Significant interactions (sex × time) were found in body mass (F = 5.18, p = 0.03, ηp2 = 0.06), body fat percentage (F = 5.31, p < 0.01, ηp2 = 0.14), and medicine ball throw (F = 10.84, p < 0.01, ηp2 = 0.13). Specifically, males exhibited a greater reduction in body mass (females: 2.70%, males: 3.47%, p < 0.05) and a substantial improvement in ball throwing performance (females: 7.74%, males: 11.47%, p < 0.01), while females experienced a greater reduction in fat mass (females: 5.34%, males: 3.15%, p < 0.01). The physical training regimen effectively influenced body composition, particularly in enhancing strength performance among males. The integration of exercise programs with military service led to a notable reduction in fat tissue and an increase in lean tissue. Hence, the development of tailored training protocols is imperative to enhance the physical capacity and overall health of military recruits, considering sex-specific characteristics and physical attributes.

The effects of combined exercise training on glucose metabolism and inflammatory markers in sedentary adults: a systematic review and meta-analysis

This systematic review and meta-analysis aimed to determine the magnitude of the effect of combined exercise training on glucose metabolism markers, adipokines, and inflammatory cytokines in non-diabetic sedentary adults. PubMed, Web of Science, Scopus, Cochrane Library electronic databases and reference lists of included studies were explored for randomized controlled trials (RCTs) that included physically inactive adults and provided combined training interventions (aerobic plus resistance exercise). Effects on fasting glucose and insulin, Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), HbA1c, adiponectin, leptin, IL-6, TNF-α, and C-reactive protein (CRP) in exercise vs control groups were analyzed using random effects meta-analysis. The Cochrane Risk of Bias Tool for Randomized Trials 2.0 (RoB 2) was used to assess the risk of bias. A total of 24 RCTs were included in the quantitative analysis. Combined exercise training significantly decrease fasting glucose (standardized mean difference, SMD: - 0.474, 95% CI [- 0.829, - 0.120], p = 0.009, 35 study arms), fasting insulin (SMD: - 1.024, 95% CI [- 1.502, - 0.545], p < 0.001, 27 study arms), HOMA-IR (SMD: - 0.946, 95% CI [- 1.450, - 0.442], p < 0.001, 23 study arms), TNF-α (SMD: - 0.972, 95% CI [- 1.361, - 0.582], p < 0.001, 10 study arms), and CRP (SMD: - 0.507, 95% CI [- 0.818, - 0.196], p = 0.001, 14 study arms). No significant effects were observed for HbA1c, adiponectin, leptin, and IL-6 levels. Random effects meta-regression models by age, sex, and intervention length were not able to explain any of the variation in the effect size of HOMA-IR. Findings from this systematic review and meta-analysis suggest that combined exercise training improves some glucose metabolism markers and inflammatory parameters in sedentary adults without diabetes.

[Association between biological maturity, body constitution and physical fitness with performance on a rowing ergometer in elite youth female rowers]

BACKGROUND

There is a gap in the literature regarding predictors of rowing performance in young rowers. Therefore, the aim of this study was to investigate associations between parameters of biological maturity, body constitution and physical fitness with rowing performance in young female elite rowers.

METHODS

A total of 26 female rowers aged 13.1 ± 0.5 years (maturity offset: + 2.2 ± 0.5 years from peak height velocity; training volume: 10 hours/week) volunteered to participate in this study. During the performance tests in March 2016/2017, biological maturity (e. g. maturity offset), body constitution (e. g. body height/mass, lean body mass, body fat mass) and physical fitness were assessed. Physical fitness tests included the assessment of muscle strength (1-RM bench pull, leg press, maximal handgrip strength), muscle power (standing long jump test), muscular endurance (trunk muscle endurance test [Bourban test]), dynamic balance (Y-balance test) and change-of-direction speed (multistage shuttle run). Finally, rowing performance was analysed using a 700-m rowing ergometer test. A linear regression analysis was computed for the models (1) biological maturity, (2) biological maturity and body constitution, and (3) biologic maturity, body constitution, and physical fitness.

RESULTS

The statistical analysis showed significant (p≤ 0.01) medium-to-large sized correlations (0.57 ≤r≤ 0.8) between biological maturity, body constitution (e. g. body height/mass, lean body mass) and physical fitness (e. g. 1-RM bench pull, maximal handgrip strength, Bourban test) with rowing performance. Model 3 with the predictors body constitution (i. e. lean mass) and muscular endurance (i. e. Bourban test) showed the largest explained variance for 700-m rowing ergometer performance (R² = 0.94, Akaike information criterion [AIC] = 82.1). Explained variance of model 3 was higher compared with model 1 (R² = 0.6, AIC = 131.5) and model 2 (R² = 0.63, AIC = 111.6).

CONCLUSIONS

As a result of this study, coaches involved in junior rowing should focus on characteristics such as biological maturity, body constitution and physical fitness (muscle strength, muscular endurance) during talent development as these correlated highly with rowing ergometer performance.

Recent Advances in Genomics-Based Approaches for the Development of Intracellular Bacterial Pathogen Vaccines

Infectious diseases continue to be a leading cause of morbidity and mortality worldwide. The majority of infectious diseases are caused by intracellular pathogenic bacteria (IPB). Historically, conventional vaccination drives have helped control the pathogenesis of intracellular bacteria and the emergence of antimicrobial resistance, saving millions of lives. However, in light of various limitations, many diseases that involve IPB still do not have adequate vaccines. In response to increasing demand for novel vaccine development strategies, a new area of vaccine research emerged following the advent of genomics technology, which changed the paradigm of vaccine development by utilizing the complete genomic data of microorganisms against them. It became possible to identify genes related to disease virulence, genetic patterns linked to disease virulence, as well as the genetic components that supported immunity and favorable vaccine responses. Complete genomic databases, and advancements in transcriptomics, metabolomics, structural genomics, proteomics, immunomics, pan-genomics, synthetic genomics, and population biology have allowed researchers to identify potential vaccine candidates and predict their effects in patients. New vaccines have been created against diseases for which previously there were no vaccines available, and existing vaccines have been improved. This review highlights the key issues and explores the evolution of vaccines. The increasing volume of IPB genomic data, and their application in novel genome-based techniques for vaccine development, were also examined, along with their characteristics, and the opportunities and obstacles involved. Critically, the application of genomics technology has helped researchers rapidly select and evaluate candidate antigens. Novel vaccines capable of addressing the limitations associated with conventional vaccines have been developed and pressing healthcare issues are being addressed.

Overweight and Obese Adult Patients Show Larger Benefits from Concurrent Training Compared with Pharmacological Metformin Treatment on Insulin Resistance and Fat Oxidation

Metformin, a drug widely used to treat insulin resistance, and training that combines aerobic and strength exercise modalities (i.e., concurrent training) may improve insulin sensitivity. However, there is a paucity of clinical trials investigating the effects of concurrent training, particularly on insulin resistance and fat oxidation in overweight and obese patients. Furthermore, only a few studies have compared the effects of concurrent training with metformin treatment. Therefore, the aim of this study was to examine the effects of a 12-week concurrent training program versus pharmaceutical treatment with metformin on maximum fat oxidation, glucose metabolism, and insulin resistance in overweight or obese adult patients. Male and female patients with insulin resistance were allocated by convenience to a concurrent training group (n = 7 (2 males); age = 32.9 ± 8.3 years; body mass index = 30 ± 4.0 kg·m^-2) or a metformin group (n = 7 (2 males); age = 34.4 ± 14.0 years; body mass index = 34.4 ± 6.0 kg·m^-2). Before and after the interventions, all participants were assessed for total body mass, body mass index, fat mass, fat-free mass, maximum oxygen consumption, maximal fat oxidization during exercise, fasting glucose, and insulin resistance through the homeostatic model assessment (HOMA-IR). Due to non-normal distribution of the variable maximal fat oxidation, the Mann-Whitney U test was applied and revealed better maximal fat oxidization (Δ = 308%) in the exercise compared with the metformin group (Δ = -30.3%; p = 0.035). All other outcome variables were normally distributed, and significant group-by-time interactions were found for HOMA-IR (p < 0.001, Δ = -84.5%), fasting insulin (p < 0.001, Δ = -84.6%), and increased maximum oxygen consumption (p = 0.046, Δ = 12.3%) in favor of the exercise group. Similar changes were found in both groups for the remaining dependent variables. Concurrent training seems to be more effective compared with pharmaceutical metformin treatment to improve insulin resistance and fat oxidation in overweight and obese adult patients with insulin resistance. The rather small sample size calls for more research in this area.

Acute and Long-Term Effects of Concurrent Resistance and Swimming Training on Swimming Performance

Dry-land resistance exercise (RT) is routinely applied concurrent to swimming (SWIM) training sessions in a year-round training plan. To date, the impact of the acute effect of RT on SWIM or SWIM on RT performance and the long-term RT-SWIM or SWIM-RT training outcome has received limited attention. The existing studies indicate that acute RT or SWIM training may temporarily decrease subsequent muscle function. Concurrent application of RT-SWIM or SWIM-RT may induce similar physiological alterations. Such alterations are dependent on the recovery duration between sessions. Considering the long-term effects of RT-SWIM, the limited existing data present improvements in front crawl swimming performance, dry-land upper and lower body maximum strength, and peak power in swim turn. Accordingly, SWIM-RT training order induces swimming performance improvements in front crawl and increments in maximum dry-land upper and lower body strength. Concurrent application of RT-SWIM or SWIM-RT training applied within a training day leads in similar performance gains after six to twelve weeks of training. The current review suggests that recovery duration between RT and SWIM is a predisposing factor that may determine the training outcome. Competitive swimmers may benefit after concurrent application with both training order scenarios during a training cycle.

Advanced strategies for development of vaccines against human bacterial pathogens

Infectious diseases are one of the main grounds of death and disabilities in human beings globally. Lack of effective treatment and immunization for many deadly infectious diseases and emerging drug resistance in pathogens underlines the need to either develop new vaccines or sufficiently improve the effectiveness of currently available drugs and vaccines. In this review, we discuss the application of advanced tools like bioinformatics, genomics, proteomics and associated techniques for a rational vaccine design.