Exploring Indicators for Training Load Control in Young Swimmers: The Role of Inspiratory Spirometry Outcomes.

One of the most important implications of technology in swimming is to control training loads. Lactate control, video-analysis of the technique or the assessment of specific actions, i.e., the vertical jump, have helped to provide load adaptation indicators in swimmers in recent decades. However, these indicators have led to a longer application time, due to their indirect procedure and the need to analyze each variable. The aim of this study was to analyze whether inspiratory spirometry values can serve as a training load control tool in swimmers. Countermovement jump (CMJ), Inspiratory Force Index (S-INDEX) and Peak Inspiratory Flow (PIF) were evaluated with a load of 3 cm H2O before, during and after performing a swimming performance test (critical speed test: specific warming up, 400 m and 100 m freestyle). Positive correlations were found between S-INDEX and jump height after warm-up, after 400 m and at the end of 100 m (Spearman = 0.470, R2 = 0.280; Spearman = 0.508, R2 = 0.392; Spearman = 0.458, R2 = 0.359, p < 0.05, respectively). Moreover, positive correlations were also found between PIF and jump height at the same evaluated moments (Spearman = 0.461, R2 = 0.305; Spearman = 0.493, R2 = 0.386; Spearman = 0.454, R2 = 0.374, p < 0.05). Both the S-INDEX and the PIF could serve as useful tools for swimmer load control, allowing coaches to make more immediate decisions.

Effectiveness of the KC@H programme compared with clinic-based rehabilitation in patients recovering from ACL reconstruction: a study protocol for a single-centre, two-arm, single-blinded, randomised controlled superiority trial.

Patients who cannot fully comply with conventional clinic-based rehabilitation (CR) sessions after ACL reconstruction (ACLR) may find additional internet-based sessions beneficial. These remote sessions include therapeutic exercises that can be done at home, potentially extending the reach of rehabilitation services to underserved areas, prolonging the duration of care and providing improved supervision. The study's main purpose is to determine if the Knee Care at Home (KC@H) programme is more effective than conventional CR alone in improving patient-reported, clinician-reported and physical functional performance outcome measures after ACLR. Additionally, the trial assesses the significance of changes in outcome measures for clinical practice. This protocol outlines a randomised controlled trial for postoperative recovery following ACLR. Adult participants of both sexes who meet specific criteria will be randomly assigned to either the CR group or the KC@H group. Only the latter group will receive internet-based sessions of therapeutic exercises at home and CR sessions. A follow-up evaluation will be conducted for both groups 12 weeks after the intervention ends. The trial protocol was approved by the Ethics Committee of the Universidade de Évora and complies with the Code of Ethics of the World Medical Association. All recordings will be stored on a secure server with limited access and deleted as soon as they are no longer needed. The KC@H programme is expected to be superior to conventional CR for patients recovering from ACLR across multiple outcome measures. Also, the programme has the potential to promote superior recovery and extend the reach and duration of care. Trial registration number: NCT05828355.

Integrating PET chemical recycling with pyrolysis of mixed plastic waste via pressureless alkaline depolymerization in a hydrocarbon solvent.

This study presents a proof of concept for a technology train that integrates polyethylene terephthalate (PET) recovery from mixed plastic waste and plastic pyrolysis. PET is depolymerized into terephthalic acid (TPA) by hydrolysis using a low volatility oil as medium, which enables (i) low-pressure operation, and (ii) a selective separation and recovery of TPA from the product mix by a simple process of filtration, washing, and precipitation. Full PET conversion and high TPA recovery (>98 %) were achieved at 260 °C. This technology train is demonstrated to be effective for processing mixed waste streams, leading to higher yield and quality of liquid product from thermal pyrolysis when compared with feedstock that has not been pre-treated. Further, the technology could be readily integrated with a plastics pyrolysis process, whereby a by-product from the pyrolysis could be used as the low-volatility oil.

Effects of an 11-Week Detraining, Imposed by the COVID-19 Confinement, on Handball Players' Shoulder Rotator Isokinetic Profile, Shoulder Range of Motion, and Ball Release Velocity.

Background and Objectives: The COVID-19 confinement significantly impacted the physical condition of athletes. However, the detraining impacts of this period on the shoulder rotator and range of motion in handball players have not been studied. Thus, the main aim of this study was to investigate the effect of this 11-week detraining period, imposed by the COVID-19 pandemic confinement, on the shoulder rotator isokinetic profile (peak torque, ratio, fatigue index), shoulder rotator and flexion range of motion, and ball release velocity in handball players. Materials and Methods: A total of 16 handball players, with a mean age of 22.38 (5.28) years, participated in this study. The isokinetic strength was assessed using two protocols (three repetitions at an angular velocity of 60°/s and 20 repetitions at an angular velocity of 180°/s). In addition, the range of motion and ball release (at jump and standing shots) were measured. All these measurements were assessed before and after the COVID-19 confinement. Results: The results showed a significant reduction in the peak torque of the external rotation of their dominant and non-dominant shoulders. In addition, confinement significantly increased the fatigue index of external rotation and internal rotation and reduced the range of motion of internal rotation. Additionally, the ball release velocity during standing and jump shots was significantly reduced. Conclusions: These results suggested that strengthening external and internal rotation as well as recovering the internal rotation range of motion may be necessary after a detraining period in order to prevent shoulder injuries.

Phase angle as a key marker of muscular and bone quality in community-dwelling independent older adults: A cross-sectional exploratory pilot study.

The aim of the present cross-sectional exploratory pilot study was to analyze the ability of the Phase Angle (PhA) to predict physical function, muscle strength and bone indicators, upon adjusting for potential confounders [age, sex, lean mass, and body mass index (BMI)]. This study included 56 physically independent older adults (age, 68.29 ± 3.01 years; BMI, 28.09 ± 4.37 kg/m2). A multi-frequency segmental bioelectrical impedance analysis was used to measure PhA at 50 KHz. Additionally, physical function was assessed through four functional capacity tests [30-sec chair-stand; seated medicine ball throw (SMBT); timed up & go; and 6-min walking test (6 MWT)], muscle strength through the handgrip test (dominant side) and maximal isokinetic strength of the dominant knee flexor and extensor. Moreover, bone indicators and body composition were assessed through the dual energy X-ray absorptiometry. PhA was significantly associated with SMBT (r = 0.375, effect size (ES) = moderate); 6 MWT (r = 0.396, ES = moderate); 30-sec chair-stand (rho = 0.314, ES = moderate); knee extension (rho = 0.566, ES = large) and flexion (r = 0.459, ES = moderate); handgrip (rho = 0.432, ES = moderate); whole-body bone mineral content (BMC) (r = 0.316, ES = moderate); femoral neck BMC (r = 0.469, ES = moderate); and femoral neck bone mineral density (BMD) (rho = 0.433, ES = moderate). Additionally, the results of multiple regression analysis demonstrated that PhA is significantly associated with SMBT (p < 0.001; R2 = 0.629), 6 MWT (p = 0.004; R2 = 0.214), knee extension (p < 0.001; R2 = 0.697), knee flexion (p < 0.001; R2 = 0.355), handgrip test (p < 0.001; R2 = 0.774), whole-body BMC (p < 0.001; R2 = 0.524), femoral neck BMC (p = 0.001; R2 = 0.249), and femoral neck BMD (p = 0.020; R2 = 0.153). The results of the preliminary analysis suggested that PhA is linked to muscle strength and some factors related to physical function and bone quality in community-dwelling older adults.

Translation, Cultural Adaptation, and Reliability of the 15D Portuguese Version: A Generic Health-Related Quality of Life (HRQoL) Instrument.

(1) Background: Purpose: The assessment of quality of life is essential to the human condition and can be measured through questionnaires. This study aims to translate and culturally adapt the 15D questionnaire to assess the population's quality of life, as well as explore its relative reliability and internal consistency; (2) Methods: The translation and cultural adaptation of the 15D questionnaire was carried out independently, considering two translations. The synthesis version was applied to eight subjects, distributed by gender. Cognitive interviews were conducted to observe clarity, acceptability, and familiarity with the version of the questionnaire. The final version of the questionnaire, in Portuguese, was again translated into the official language by two translators who had never had contact with the questionnaire. To assess the test-retest reliability and internal consistency of the 15D questionnaire, 43 participants were interviewed; (3) Results: Participants indicated that they had some doubts about dimensions, breathing, and discomfort and symptoms; however, as there were no suggestions for change, the questionnaire had no changes. Items were clear and understandable. Internal consistency was observed using Cronbach's alpha, with values between 0.76 and 0.98. The test-retest reliability values were between 0.77 and 0.97; and (4) Conclusions: The Portuguese version of the 15D questionnaire was proved to be equivalent to the English version and to be reliable for the Portuguese population. This instrument is easy to access and apply.

Changes in Muscular Activity in Different Stable and Unstable Conditions on Aquatic Platforms.

The present study aimed to analyse and compare the muscle activity of twelve participants (seven men and five women) (age 20.1 ± 0.9 years; height 170.5 ± 10 cm; body mass: 64.86 ± 8.3 kg) in two exercises, each with two variants: squat (dynamic and static) and plank (hands and elbows) in a stable environment on land and an unstable environment on an aquatic platform. The erector spinae, biceps femoris, rectus femoris, external oblique, and rectus abdominis muscles were evaluated using surface electromyography. The dynamic squat increases the recruitment of the biceps femoris and external oblique, while the static squat demands greater activation of the rectus femoris. The elbow plank exercise increases the recruitment of erector spinae muscles, and the hand plank exercise increases the recruitment of the erector spinae and external oblique. In conclusion, performing exercises in unstable conditions on an aquatic platform slightly increases muscle recruitment.

Efeitos do treinamento físico de vibração de corpo inteiro nos níveis de força de membros inferiores em idosos / Efectos del entrenamiento con ejercicios de vibración de cuerpo entero en los niveles de fuerza de miembros inferiores de adultos mayores / Effects of whole-body vibration exercises on strength levels of lower limb on elderlies

RESUMO O objetivo do presente estudo foi analisar os efeitos do exercício de vibração de corpo inteiro sobre os níveis de força nos membros inferiores de idosos. A amostra foi composta por 15 homens fisicamente ativos (idade: 62,5 ± 2,62 anos). Foram realizadas oito semanas de treinamento com plataforma vibratória, com sessões de 20 minutos de vibração utilizando frequências crescentes de 15 a 30 Hz, com exposição de 30 segundos de vibração e 30 segundos de descanso. A cada dois minutos houve um aumento de frequência de 1 Hz. Os indivíduos foram instruídos a ficar em pé, com os pés afastados na largura dos ombros, joelhos flexionados a 130°, braços estendidos, segurando firmemente a máquina. O procedimento foi realizado duas vezes por semana com intervalo de um dia. A força foi avaliada usando um dinamômetro dorsal em exercícios de extensão de joelho e extensão de coluna lombar. Os testes de força foram realizados na quarta e oitava semana após a última sessão de treinamento. Resultados: Ao final de oito semanas, foi possível observar ganhos significativos de força nos músculos envolvidos no exercício de extensão do joelho (p = 0,01) e na extensão da coluna lombar (p = 0,031). Conclusão: observou-se que o treinamento com vibrações de corpo inteiro promoveu melhora nos níveis de força nos membros inferiores dos idosos participantes do estudo.

RESUMEN El objetivo del presente estudio fue analizar los efectos del ejercicio de vibración de todo el cuerpo sobre los niveles de fuerza en los miembros inferiores de adultos mayores. La muestra estuvo formada por 15 hombres físicamente activos (edad: 62,5 ± 2,62 años). Se realizaron ocho semanas de entrenamiento con plataforma vibratoria, con sesiones de 20 minutos de vibración utilizando frecuencias crecientes de 15 a 30 Hz, con exposición de 30 segundos de vibración y 30 segundos de descanso. Cada dos minutos había un aumento de frecuencia de 1 Hz. Se indicó a los individuos que permanecieran de pie con los pies separados a la altura de los hombros, las rodillas flexionadas a 130º y los brazos extendidos sujetando firmemente los apoyamanos de la máquina. El procedimiento se realizó dos veces por semana con un intervalo de un día. La fuerza se evaluó mediante un dinamómetro dorsal en los ejercicios de extensión de rodilla y extensión de columna lumbar. Las pruebas de fuerza se realizaron en la cuarta y octava semana después de la última sesión de entrenamiento. Resultados: Al final de las ocho semanas, fue posible observar ganancias significativas en la fuerza en los músculos involucrados en el ejercicio de extensión de rodilla (p = 0,01) y en la extensión de columna lumbar (p = 0.031). Conclusión: se pudo observar que el entrenamiento con vibraciones de todo el cuerpo promovió una mejora en los niveles de fuerza en los miembros inferiores de los adultos mayores participantes del estudio.

ABSTRACT The present study was to analyze the effects of whole-body vibration exercise on strength levels in the lower limbs in elderly subjects. The sample consisted of 15 physically active individuals (62.5±2.62 years old). All volunteers were male gender. They were submitted to eight weeks of training with a vibrating platform were carried out, with sessions of 20 minutes of vibration using increasing frequencies from 15 to 30 Hz, with exposure of 30 seconds of vibration and 30 seconds of rest. Every two minutes there was an increase in the frequency of 1 Hz. The individuals were instructed to stay in the standing position with their feet shoulder-width apart, knees flexed at 130º, arms outstretched holding firmly on the machine's hand rests. The procedure was performed twice a week with an interval of one day. Strength was assessed using a dorsal dynamometer in the knee extension and lumbar spine extension exercises. Strength tests were performed in the fourth and eighth weeks after the last training session. Results: At the end of eight weeks, it was possible to observe significant gains in strength in the muscles involved in the knee extension exercise (p = 0.0001) and in the lumbar spine extension (p = 0.031) after the eight weeks of intervention. Conclusion: It was possible to observe that the whole-body vibration training promoted an improvement in the strength levels of the elderly participants in the study.

Heart Rate Variability Monitoring during a Padel Match.

Padel, an increasingly popular sport, presents some associated cardiovascular risks, which can be prevented by heart rate variability (HRV) monitoring. However, there is no study worldwide that characterizes HRV during padel games. Therefore, this study aims to monitor HRV responses and characterize them using linear and non-linear metrics at three timepoints: at baseline, during a game, and during recovery. Twenty-seven amateur participants had their HRV monitored before, during, and after a 90 min padel game. We extracted time, frequency, and non-linear measures with MATLAB for baseline, rest period, and at three periods of 5 min during the game. The differences in measures were assessed through an ANOVA. The autonomic modulation was affected by the padel match in amateur players. In this regard, the root mean square of successive differences between normal heartbeats (RMSsd), Poincaré plot (perpendicular standard deviation (SD1) and horizontal standard deviation (SD2)), sample entropy (SampEn), low frequencies (LF), and very low frequencies (VLF) were significantly reduced during the game, whereas alpha-2, high frequencies (HF), and the ratio between low and high frequencies (LF/HF) increased during the game. Furthermore, an abrupt change was found in the autonomic modulation between game and recovery assessments, which suggests the need to rethink the practices of cool-down protocols. The multiple timepoints analyzed during this study allow us to investigate the evolution of different HRV measures in the time, frequency, and non-linear domains, clarifying the interpretation of the variables, especially the less-investigated ones such as the non-linear measures.

The Effect of Periodization on Training Program Adherence.

The present research aimed to study the effect of three different training periodization (traditional, reverse, and free training) on the aerobic performance, motivation, and adherence of physically active athletes. We analysed the adherence to three different periodization training programs: traditional, reverse, and free training periodization on the adherence of amateur triathletes. For this aim, the individual adherence, motivation, and aerobic performance time and heart rate (in a 1000 m running test) were evaluated before and after the completion of the three different 8-week periodization programs. The level of adherence to the reverse periodization was significantly higher than in traditional and free training. The number of dropouts in reverse and traditional periodization was similar but lower than in the free training. Finally, neither of the periodization programs improved aerobic performance and reverse training periodization decreased heart rate of participants in a 1000 m running test.

Short-Term Skin Temperature Responses to Endurance Exercise: A Systematic Review of Methods and Future Challenges in the Use of Infrared Thermography.

BACKGROUND: Body temperature is often assessed in the core and the skin. Infrared thermography has been used to measure skin temperature (Tsk) in sport research and clinical practice. This study aimed to explore the information reported to date on the use of infrared thermography to detect short-term Tsk responses to endurance exercise and to identify the methodological considerations and knowledge gaps, and propose future directions. METHOD: A web search (PubMed, Science Direct, Google Scholar, and Web of Science) was conducted following systematic review guidelines, and 45 out of 2921 studies met the inclusion criteria (endurance sports, since 2000, English, full text available). RESULTS: A total of 45 publications were extracted, in which most of the sample were runners (n = 457, 57.9%). Several differences between IRT imaging protocols and ROI selection could lead to potential heterogeneity of interpretations. These particularities in the methodology of the studies extracted are widely discussed in this systematic review. CONCLUSIONS: More analyses should be made considering different sports, exercise stimuli and intensities, especially using follow-up designs. Study-derived data could clarify the underlying thermo physiological processes and assess whether Tsk could be used a reliable proxy to describe live thermal regulation in endurance athletes and reduce their risk of exertional heat illness/stroke. Also more in-depth analyses may elucidate the Tsk interactions with other tissues during exercise-related responses, such as inflammation, damage, or pain.

Development and validation of a continuous fall risk score in community-dwelling older people: an ecological approach.

BACKGROUND: Fall risk assessment in older people is of major importance for providing adequate preventive measures. Current predictive models are mainly focused on intrinsic risk factors and do not adjust for contextual exposure. The validity and utility of continuous risk scores have already been demonstrated in clinical practice in several diseases. In this study, we aimed to develop and validate an intrinsic-exposure continuous fall risk score (cFRs) for community-dwelling older people through standardized residuals. METHODS: Self-reported falls in the last year were recorded from 504 older persons (391 women: age 73.1 ± 6.5 years; 113 men: age 74.0 ± 6.1 years). Participants were categorized as occasional fallers (falls ≤1) or recurrent fallers (≥ 2 falls). The cFRs was derived for each participant by summing the standardized residuals (Z-scores) of the intrinsic fall risk factors and exposure factors. Receiver operating characteristic (ROC) analysis was used to determine the accuracy of the cFRs for identifying recurrent fallers. RESULTS: The cFRs varied according to the number of reported falls; it was lowest in the group with no falls (- 1.66 ± 2.59), higher in the group with one fall (0.05 ± 3.13, p < 0.001), and highest in the group with recurrent fallers (2.82 ± 3.94, p < 0.001). The cFRs cutoff level yielding the maximal sensitivity and specificity for identifying recurrent fallers was 1.14, with an area under the ROC curve of 0.790 (95% confidence interval: 0.746-0.833; p < 0.001). CONCLUSIONS: The cFRs was shown to be a valid dynamic multifactorial fall risk assessment tool for epidemiological analyses and clinical practice. Moreover, the potential for the cFRs to become a widely used approach regarding fall prevention in community-dwelling older people was demonstrated, since it involves a holistic intrinsic-exposure approach to the phenomena. Further investigation is required to validate the cFRs with other samples since it is a sample-specific tool.

The Acute Effects of a Swimming Session on the Shoulder Rotators Strength and Balance of Age Group Swimmers.

The purpose of this study was to analyze the acute effects of a standardized water training session on the shoulder rotators strength and balance in age group swimmers, in order to understand whether a muscle-strengthening workout immediately after the water training is appropriate. A repeated measures design was implemented with two measurements performed before and after a standardized swim session. 127 participants were assembled in male (n = 72; age: 16.28 ± 1.55 years, height: 174.15 ± 7.89 cm, weight: 63.97 ± 6.51 kg) and female (n = 55; age: 15.29 ± 1.28 years, height: 163.03 ± 7.19 cm, weight: 52.72 ± 5.48 kg) cohorts. The isometric torque of the shoulder internal (IR) and external (ER) rotators, as well as the ER/IR ratios, were assessed using a hand-held dynamometer. Paired sample t-tests and effect sizes (Cohen's d) were used (p ≤ 0.05). No significant differences were found on the shoulder rotators strength or balance in males after training. Females exhibited unchanged strength values after practice, but there was a considerable decrease in the shoulder rotators balance of the non-dominant limb (p < 0.01 d = 0.366). This indicates that a single practice seems not to affect the shoulders strength and balance of adolescent swimmers, but this can be a gender specific phenomenon. While muscle-strengthening workout after the water session may be appropriate for males, it can be questionable regarding females. Swimming coaches should regularly assess shoulder strength levels in order to individually identify swimmers who may or may not be able to practice muscle strengthening after the water training.

Comparison of cardiorespiratory resistance in different menstrual cycle phases in female futsal players

Introduction: This study was aimed to investigated and compare the cardiorespiratory resistance of futsal players during the follicular and luteal phases of the menstrual cycle.Material and methodsFourteen female players (age: 24.1±4.1 years; body mass: 59.6±9.1kg; height: 1.64±0.06m; index body mass: 22.1±2.8kg/m2) were submitted to a cardiorespiratory resistance test, that was performed in a calibrated treadmill, where we had as reference for the calculation of VO2max. Each subject also performed two evaluations of the intended test, corresponding to the phases of the menstrual cycle: folicular phase (day 8±3) and luteal phase (day 20±2).ResultsThe results of the present research showed that there were significant changes, showing higher values of the cardiorespiratory resistance in luteal phase (VO2max=41.199ml/kg/min) compared to folicular phase of the menstrual cycle (VO2max=39.030ml/kg/min), where p=0.043. There is still a great deal of controversy in the existing literature when considering a relationship of menstrual cycle phases to physical exercise.ConclusionThe cardiorespiratory resistance of futsal players was increased in luteal phase compared to follicular phase, and management of the training is advisable, namely in type and volume. (AU)

Conversion of agricultural waste into stable biocrude using spinel oxide catalysts.

Biomass, the feedstock for biocrude and ultimately renewable diesel is a low energy density feedstock. The transport of this feedstock over long distance has been proven to be a major burden on the commercialisation of biorefining. Therefore, it has been generally accepted that biomass should be upgraded to biocrude (a relatively high energy density liquid) in close proximity to the biomass sources. The biocrude liquid would then be transported to a biorefinery. Biocrude contains large amounts of oxygen (generally up to 38 wt%) that is removed from the crude in the refining process. In this study, we have synthesised a range of spinel oxide based catalysts to remove oxygen from the biocrude during the catalytic fast pyrolysis. The activity of spinel oxide (MgB2O4 where B = Fe, Al, Cr, Ga, La, Y, In) catalysts were screened for the pyrolysis reaction. While all the tested spinel oxides deoxygenated the pyrolysis vapour, MgCr2O4 was found to be effective in terms of oxygen removal efficiency relative to the quantity of bio oil produced.

High Levels of Physical Activity May Promote a Reduction in Bone Mineral Density in Peritoneal Dialysis.

Background and objectives: Peritoneal dialysis (PD) patients are expected to present lower levels of physical activity, unhealthy changes at the body composition level, and low levels of strength. Firstly, this study aimed to report the sex differences in physical activity, body composition and muscle strength and the relations among these variables. Secondly, we analyze the relationship between physical activity and biochemical parameters. Materials and Methods: Thirty-four patients (13 women and 21 men) participated in this study. Body composition was assessed by bioimpedance and dual-energy X-ray absorptiometry (DXA), and maximum isokinetic unilateral strength, analytical parameters and physical activity levels were evaluated. Results: The men showed higher values for weight, height, lean body mass, bone mineral content, bone mineral density (BMD) and total body water, while women showed higher values for the percentage of fat mass and hydration of lean body mass (p < 0.05). No differences between the sexes were found in different levels of physical activity; however, males registered significantly higher values for isokinetic strength variables except for knee extensor strength. BMD was positively related to sedentary activity and negatively related to moderate and vigorous activity (r = 0.383 and r = -0.404, respectively). Light physical activity was negatively correlated with albumin (r = -0.393) and total protein (r = -0.410) levels, while moderate/vigorous activity was positively correlated with urea distribution volume (r = 0.446) and creatinine clearance (r = 0.359) and negatively correlated with the triglyceride level (r = -0.455). Conclusions: PD patients with higher levels of physical activity present better results in terms of body composition and biochemical parameters. Additional studies should be conducted to clarify the relation between physical activity level and BMD.

Post high intensity pull-over semi-tethered swimming potentiation in national competitive swimmers.

BACKGROUND: The swimming community has shown considerable interest in using dry-land warm-ups as a method of impacting performance. This study compared the effects of high-resistance pull-over and swimming warm-up in semi-tethered resisted swimming. METHODS: An incremental-load semi-tethered swimming test was individually administered in 20 national-competitive swimmers to determine the load maximizing swimming power. In different sessions, participants tested such a load 6 min after a swimming warm-up (SWU) or a dry-land warm-up (DLWU: 3 pull-over reps at 85% of the one-repetition maximum). Kinetic variables (velocity, force, acceleration, impulse, power rate of force development [RFD] and intra-cycle variation), were obtained with a linear encoder through trapezoidal integration regarding time. Kinematic variables (distance, time, stroke-rate and stroke-length), were obtained by video recordings. The differences between protocols were observed by paired-samples t-test (ANOVA). Pearson's coefficient explored correlations between kinetics and kinematics variables; significance was set at P<0.05. RESULTS: DLWU increased RFD (34.52±16.55 vs. 31.29±13.70 N/s; Δ=9.35%) and stroke-rate (64.70±9.84 vs. 61.56±7.07 Hz; Δ=5.10%) compared to SWU, but decreased velocity, force, acceleration, impulse and power. During the incremental-load test velocity and power were higher than obtained after SWU (1.21±0.14 vs. 1.17±0.12 m/s; Δ=3.06%), (51.38±14.93 vs. 49.98±15.40 W; Δ=2.72%), suggesting enhancements prompted by the test itself. Correlations between stroke-length with impulse (r=0.76) and power (r=0.75) associated kinetics with kinematics. CONCLUSIONS: Potentiation responses were present after the dry-land warm-up. However, swimmers may benefit more from submaximal prolonged conditioning activities such as resisted swimming rather than high-resistance dry-land sets to obtain performance enhancements.

Effects on performance of active and passive hypoxia as a re-warm-up routine before a 100-metre swimming time trial: a randomized crossover study.

Passive and active hypoxia could be used as a tool during a transitional phase to maintain the effects of warm-up and optimize athletic performance. Our purpose was to evaluate and compare the effects of four different re-warm-up strategies, i.e. rest in normoxia (RN) at FiO2 = 20.9%, rest in hypoxia (RH) at FiO2 = 15%, active (5 minutes dryland-based exercise circuit) in normoxia (AN) and active in hypoxia (AH), during the transitional phase, on subsequent 100 m maximal swimming performance. Thirteen competitive swimmers (n = 7 males; n = 6 females; age: 15.1±2.1 years; height: 164.7±8.8 cm; weight: 58.1±9.7 kg; 100 m season's best time 72.0±11.8 s) completed a 20-minute standardized in-water warm-up followed by a 30-minute randomized transitional phase and 100 m freestyle time trial. Compared to AH (73.4±6.2 s), 100 m swim time trials were significantly (p = 0.002; η 2 = 0.766) slower in RN (75.7±6.7 s; p = 0.01), AN (75.2±6.7 s; p = 0.038) and RH (75.0±6.4 s; p = 0.009). Moreover, compared to AH (36.3±0.4ºC), tympanic temperature was significantly lower (p<0.001; η 2 = 0.828) at the end of the transitional phase in passive conditions (RN: 35.9±0.6; p = 0.032; RH: 36.0±0.4; p = 0.05). In addition, countermovement jump height at the end of the transitional phase was significantly higher in active than in passive conditions (p = 0.001; η2 = 0.728). A dryland-based circuit under hypoxia could be useful to swimmers, once it has attenuated the decline in tympanic temperature during a 30-minute transitional phase after warm-up, improving 100 m swimming performance in young amateur swimmers.

A review on advanced catalytic co-pyrolysis of biomass and hydrogen-rich feedstock: Insights into synergistic effect, catalyst development and reaction mechanism.

The depletion of fossil fuel reserves and the growing demand for alternative energy sources are the main drivers of biomass and carbonaceous waste utilization. Particularly, non-edible lignocellulosic biomass is the most attractive renewable feedstock due to its abundance. Pyrolysis of biomass produces highly oxygenated compounds with oxygen content >35 wt%. The cost-effective elimination of oxygen from the pyrolysis oil is the most challenging task impeding the commercialization of biomass to biofuel processes. The effective hydrogen/carbon ratio in biomass pyrolysis oil is low (0.3), requiring external hydrogen supply to produce hydrocarbon-rich oils. Exploiting hydrogen-rich feedstock particularly, solid waste (plastic, tyre and scum) and other low-cost feedstock (lubricant oil, methane, methanol, and ethanol) offer an eco-friendly solution to upgrade the produced bio-oil. Multi-functional catalysts that are capable of cleaving oxygen, promoting hydrogen transfer and depolymerisation must be developed to produce hydrocarbon-rich oil from biomass. This review compares catalytic co-pyrolysis studies based on zeolites, mesoporous silica and metal oxides. Furthermore, a wide range of catalyst modifications and the role of each feedstock were summarised to give a complete picture of the progress made on biomass co-pyrolysis research and development.

Red-mud based porous nanocatalysts for valorisation of municipal solid waste.

Red mud samples were used to catalyse in-situ co-pyrolysis of pinewood and low-density polyethylene for the production of high-quality bio-oil. The sodium cation in the crude red-mud was exchanged with barium and calcium cations and further tested to explore their role in oil upgrading. The relationship between red-mud catalytic activity and its constituents was explored using synthetic sodalite. The red-mud catalysts exhibited a considerable aromatisation capacity compared to the thermal co-pyrolysis, as the selectivity towards monocyclic aromatic hydrocarbons increased from 12.7 to 19.6%, respectively. Long-chain molecules cracking was more significant in synthetic sodalite associated with their acidic active sites. The addition of barium and calcium cations to the red-mud largely improved oxygen elimination as a result of the enhanced catalyst basicity. In contrast, the aromatisation ability of red-mud significantly impeded by the large cation size (Ba2+ and Ca2+) due to the limited diffusion of pyrolysis vapours to the active sites. Ba-exchanged red-mud catalysts reduced the content of carboxylic acids in the bio-oil to 1.8 % while maintained a high yield of the organic fraction (34 %). Ca-exchanged red-mud catalysts produced the lowest fraction of oxygenated compounds (35.1 %); however, the organic phase yield was as low as 23.6 %. The modified red-mud catalysts reduced the fraction of oxygenated compounds from 69.9-35.1% during the biomass-plastic co-pyrolysis.