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Davies, TB, Halaki, M, Orr, R, Mitchell, L, Helms, ER, Clarke, J, and Hackett, DA. Effect of set structure on upper-body muscular hypertrophy and performance in recreationally trained men and women. J Strength Cond Res XX(X): 000-000, 2021-This study explored the effect of volume-equated traditional-set and cluster-set structures on muscular hypertrophy and performance after high-load resistance training manipulating the bench press exercise. Twenty-one recreationally trained subjects (12 men and 9 women) performed a 3-week familiarization phase and were then randomized into one of two 8-week upper-body and lower-body split programs occurring over 3 and then progressing to 4 sessions per week. Subjects performed 4 sets of 5 repetitions at 85% one repetition maximum (1RM) using a traditional-set structure (TRAD, n = 10), which involved 5 minutes of interset rest only, or a cluster-set structure, which included 30-second inter-repetition rest and 3 minutes of interset rest (CLUS, n = 11). A 1RM bench press, repetitions to failure at 70% 1RM, regional muscle thickness, and dual-energy x-ray absorptiometry were used to estimate changes in muscular strength, local muscular endurance, regional muscular hypertrophy, and body composition, respectively. Velocity loss was assessed using a linear position transducer at the intervention midpoint. TRAD demonstrated a significantly greater velocity loss magnitude (g = 1.50) and muscle thickness of the proximal pectoralis major (g = -0.34) compared with CLUS. There were no significant differences between groups for the remaining outcomes, although a small effect size favoring TRAD was observed for the middle region of the pectoralis major (g = -0.25). It seems that the greater velocity losses during sets observed in traditional-set compared with cluster-set structures may promote superior muscular hypertrophy within specific regions of the pectoralis major in recreationally trained subjects.

This study aimed to explore the relationship between exercise and circulating microparticles (CMPs). PubMed, Web of Science, Embase, and the Cochrane Library databases were searched until August 13, 2020, using the terms "exercise" and "cell-derived microparticles." The Cochrane tool of risk of bias and the Methodological Index for Non-Randomized Studies were used to grade the studies. Twenty-six studies that met criteria were included in this review, including one before-after self-control study, 2 cohort studies, 4 randomized control trials, 5 case-control studies, and 14 descriptive studies. The studies were divided into a single bout and long-term exercise. The types of MPs contained endothelium-derived microparticles (EMPs), leukocyte-derived microparticles (LMPs), platelet-derived microparticles (PMPs), and erythrocyte-derived microparticles (ErMPs). This first systematic review found that the levels of CMPs continued to increase after a single bout of exercise in untrained subjects and were lower in trained subjects. PMPs expressed a transient increase after a single bout of exercise, and the proportion and duration of PMPs increment reduced in long-term exercise. Most studies showed a decline in LMPs in trained subjects after a single bout and long-term exercise, and variable changes were found in EMPs and ErMPs after exercise. A single bout of exercise drives the vessels exposed to high shear stress that promotes the formation of CMPs. However, the decline in CMPs in trained subjects may be attributed to the fact that they have a better ability to adapt to changes in hemodynamics and cellular function during exercise.

Olympic weightlifting movements and their derivates are commonly used within resistance training sessions. The aim of the present study was to assess the influence of different rest intervals (RI) over five sets of the high-pull (HP) on power output performance, lactate concentration [La] and rating of perceived exertion (RPE) responses in trained subjects. Eleven well-trained males attended four testing sessions. The first session consisted of 1 repetition maximum (1RM) assessment. The next three sessions consisted of the same protocol (5 sets x 6 repetitions at 80% 1RM in the HP) but differing in the RI between sets used (1, 2 and 3 min). No significant power output decreases over the five sets in any RI condition. [La] did not significantly differ between RI conditions. The 1 min RI condition led to greater RPE values (6.5 ± 1.8) than both 2 (5.4 ± 1.6) and 3 min RI (5.0 ± 1.8). The present study shows that short RIs (i.e., 1 min) can be used by strength coaches to design more time-efficient sessions. The use of RPE during power training sessions should be considered as a sensitive tool to quantify training intensity.

Esta bem estabelecido na literatura que o treinamento de forca (TF) e uma modalidade eficiente para aumentar a massa muscular, reduzir gordura e melhorar a saude de forma geral em varias populacoes. O objetivo do estudo foi comparar o efeito de dois microciclos no TF com os protocolos de 20 e 40 series semanais por grupo muscular, se existe alteracao na carga total levantada (CTL), fadiga, recuperacao, bem-estar e afetividade em sujeitos treinados. 28 homens higidos (idade: 23,1 ± 4,7 anos; massa corporal: 75,6 ± 10,9 kg; estatura: 176 ± 7 cm). Todos os sujeitos eram treinados em forca, isto e, praticavam TF sistematicamente, pelo menos tres sessoes por semana, ha pelo menos um ano (experiencia de treinamento: 3,3 ± 2,1 anos; frequencia semanal: 5,0 ± 0,8; forca relativa supino: 1,2 ± 0,1; forca relativa agachamento: 1,7 ± 0,2). Este estudo seguiu um delineamento de 2 semanas e foi randomizado de forma aleatoria para um dos dois grupos: 20 series semanais por grupo muscular (G20, n = 15) e 40 series semanais por grupo muscular (G40, n = 13). Para o programa de TF, consistiu em 9 exercicios direcionados a cada um dos principais grupos musculares, sendo dividido entre treino A e B que era repetido duas vezes na semana, durante duas semanas. Foi feito o monitoramento da carga total levantada (CTL), percepcao subjetiva da fadiga (PSF), percepcao subjetiva da recuperacao (PSR), percepcao subjetiva do bem-estar (PBE), escala da afetividade (EA). Para CTL foi observado um efeito significante do tempo (p 0,05). Conclui-se que individuos treinados em forca podem aumentar a CTL em ~9% na segunda semana apos o inicio da intervencao, acompanhado por um aumento na percepcao de recuperacao e bem-estar e sem promover alteracoes na afetividade e na percepcao de fadiga.

Background: Acute and chronic supratherapeutic treatment with the commonly used beta2-agonist salbutamol has the potential to enhance sprint performance and muscle strength. However, little is known about the performance effects of short-term daily permitted inhaled treatment vs oral prohibited treatment in accordance with the 2020 Prohibited List issued by the World Anti-Doping Agency (WADA). Methods: Herein, we investigated the effect of twice-daily treatment with 400 μg inhaled or 4 mg oral salbutamol for 1 week on repeated sprint performance in 19 healthy well-trained men and women utilizing a randomized open-label crossover design. Before and after each treatment period, and a 12-16 hours washout to avoid an acute effect of salbutamol, subjects performed a repeated sprint test (3 × 30-second Wingate). Results: Neither oral nor inhaled salbutamol enhanced peak power (oral; 3.0 W; 95% CI −6.8 to 12.8 W; and inhaled; −3.8 W; 95% CI −14.3 to 6.8 W) or mean power (oral; −2.1 W; 95% CI −4.7 to 8.9 W and inhaled; −1.6 W; 95% CI −5.6 to 8.9 W) during the repeated sprint test irrespective of gender. Conclusions: These findings indicate that 1 week is insufficient for salbutamol to induce any relevant effect on repeated sprint performance in trained individuals.

Green, MS, Kimmel, CS, Martin, TD, Mouser, JG, and Brune, MP. Effect of carbohydrate mouth rinse on resistance exercise performance. J Strength Cond Res 36(7): 1916-1921, 2022-A carbohydrate mouth rinse (CMR) has been shown to enhance short duration endurance performance and raises the possibility that a similar strategy could improve performance during resistance exercise. Eighteen male and female (N = 36) resistance trained subjects (mean values ± SD; age: 21.5 ± 1.6 years, height: 1.72 ± 0.09 m, body mass: 72.8 ± 13.4 kg, and body fat: 16.7 ± 5.8%) performed 3 experimental visits during which bench press resistance exercise (4 × 10 repetitions at 65% of 1 repetition maximum [1RM] with 120 seconds recovery) and repetitions to failure at 60% 1RM were performed. Subjects rinsed 25 ml of water (WAT), noncaloric placebo (PLA), or 6.4% maltodextrin (CHO) solution for 10 seconds during exercise in a crossover, counter-balanced manner. Rating of perceived exertion (RPE), pleasure-displeasure (FS), number of repetitions to fatigue (REPS), and postexercise blood glucose (GLU) and lactate (LA) were measured. Compared to WAT (17.7 ± 0.8), PLA (19.0 ± 0.7; p = 0.025), and CHO (18.7 ± 0.8; p = 0.039) treatments resulted in higher REPS, with no difference between PLA and CHO treatments (p = 0.310). Rating of perceived exertion progressively increased each set (p0.0001), but was not affected by treatment (p = 0.897). Pleasure-displeasure declined during recovery from sets 3 and 4 (p0.05) but was also not affected by treatment (p = 0.692). Postexercise GLU (p = 0.103) and LA (p = 0.620) were not different between treatments. Although a placebo effect was present for REPS, this study failed to detect an effect of CMR on REPS, RPE, FS, GLU, or LA on upper-body resistance exercise.

هدف البحث إلى التعرف على فعالية البرنامج التدريبى في تنمية الذاکرة العاملة وخفض التلعثم لدى الأطفال ذوى الإعاقة الفکرية البسيطة، وتکونت العينة من (20) طفلا تراوحت أعمارهم ما بين (9 – 12) عاما، بمتوسط عمرى قدره (10.62)، وانحراف معيارى (0.69)، وتم تقسيمهم إلى مجموعتين متساويتين الأولى تجريبية، والثانية ضابطة، قوام کل منهما (10) أطفال، واشتملت أدوات البحث على مقياس الذکاء لـ ستانفورد – بينية (الصورة الخامسة) تقنين: محمود أبو النيل (2011)، مقياسي الذاکرة العاملة وشدة التلعثم من إعداد الباحثين، والبرنامج التدريبي، وأسفرت عن وجود تحسن دال لدى المجموعة التجريبية فى الذاکرة العاملة وخفض التلعثم. The aim of the present research was to identify the effectiveness of a training program in improving working memory and its impact on stuttering severity among children with mild Intellectual Disability (ID). The participants were (20) children with ID between 9-12 years of age (mean age= 10.62 yrs. SD= 0.69). They were equally divided into an experimental group and a control one. To collect data, the Stanford-Binet Intelligence Scales (5th ed) (Mahmoud Abu-El Neil, 2011) and working memory and stuttering severity scales (Prepared by the researchers) were used. Results indicated the program has been successful in developing working memory which in turn reduced stuttering severity among the trained subjects.

Background High-intensity training, a still unexplored exercise for individuals with Parkinson's disease, is positively related with increased functionality and aerobic profile in healthy individuals. The aim of this work was to evaluate the feasibility, safety, and acceptance of sprint running in individuals with mild-to-moderate Parkinson's. Additionally, we compared sprint biomechanical outputs of force, velocity and power between individuals with Parkinson's disease and healthy. Methods Physically trained subjects with Parkinson's, men, (n = 16, 64:9.01 years, stage between 1 and 3 in the Hoehn and Yahr, 16.8:7.1 at Unified Parkinson's disease Rating Scales, and control group (n = 21, 65:9.27 years) performed 20 m sprint sessions. We analyzed the self-reported satisfaction and acceptance using a self-administered questionnaire, and the sprint biomechanics and performance based on high-speed video recordings. Findings All participants completed the tests with high feasibility, acceptability and satisfaction scores. The sprint maximal force and maximal power outputs were higher in Parkinson's disease. Conversely, control group showed higher mechanical effectiveness values. Interestingly, no difference in velocity capabilities and overall 20-m sprint performance was observed between groups, possibly explained by different mechanical strategies in both groups over the sprint accelerations. Linear regression analyses showed that physical qualities are predictors of mechanical effectiveness, and mechanical variables are important determinants of sprint performance on Parkinson's disease. Interpretation Sprint is a feasible exercise for people with mild-to-moderate Parkinson's disease. Even though differences in physical qualities and mechanical effectiveness exist between subjects with Parkinson's disease and healthy, there is no overall substantial impact on sprint running performance.

Summary Background Control of laryngeal muscles is required to manipulate pitch, volume, and voice quality. False vocal fold activity (FVFA) refers to the constriction and release of constriction of the false vocal folds. True vocal fold mass (TVFM) represents the cross-sectional thickness of the vocal folds. Larynx height (LH) refers to the vertical position of the larynx in the neck. To date, studies of voice control have examined the effects of these parameters separately. No study has investigated the impact of instructed systematic manipulation of these parameters on acoustic voice measures in vocally healthy trained subjects. Aims This study examined the effects of systematically manipulating FVFA, TVFM, and LH on several acoustic voice measures. Method Twelve vocally trained speakers were instructed to use specific techniques to achieve experimental conditions of constriction and release of constriction of FVFA, thicker and thinner TVFM, and normal and low LH. Each condition was implemented in combination with manipulating the other parameters. Voice recordings of sustained vowel /a/ and Rainbow Passage were obtained for all laryngeal manipulation conditions and underwent acoustic analyses for fundamental frequency (F0), signal typing, harmonics-to-noise ratio (HNR), cepstral peak prominence (CPP), and vocal relative intensity. Results Constricted FVFA caused more aperiodicity in the signals, lower CPP, and lower vocal relative intensity than release of constriction. Thicker TVFM resulted in significantly higher CPP and vocal relative intensity than thinner TVFM. Modifying TVFM did not affect F0 and HNR. Low LH had significantly lower F0 but did not impact on HNR, CPP, and intensity. Conclusions The effects of systematic manipulation of each laryngeal parameter resulted in independent acoustic effects without measurable interaction. Release of constriction of FVFA, thicker TVFM, and low LH were configurations that resulted in more optimal acoustic signals.

The aim of the present study was to determine changes occurring in the erythrocyte concentrations of arsenic (As), cadmium (Cd) and lead (Pb) in highly trained males, moderately trained males and sedentary men living in the same area of Extremadura (Spain). Thirty sedentary subjects (24.34 ± 3.02 years) with no sports practice and a less active lifestyle formed the control group (CG). Twenty-four moderately trained subjects (23.53 ± 1.85 years), who practised sports at a moderate level between 4 and 7 h/week, without any performance objective and without following any type of systematic training, formed the group of subjects with a moderate degree of training (MTG). And 22 professional cyclists (23.29 ± 2.73 years) at the beginning of their sports season, who trained for more than 20 h/week formed the high-level training group (HTG). Erythrocyte samples from all subjects in a fasting stage were collected, washed and frozen at −80 °C until analysis. Erythrocyte analysis of the trace elements As, Cd and Pb was performed by inductively coupled plasma mass spectrometry (ICP-MS). As concentration was lower in CG (p

Prestes, J, Tibana, RA, de Araujo Sousa, E, da Cunha Nascimento, D, de Oliveira Rocha, P, Camarco, NF, Frade de Sousa, NM, and Willardson, JM. Strength and muscular adaptations after 6 weeks of rest-pause vs. traditional multiple-sets resistance training in trained subjects. J Strength Cond Res 33(7S): S113-S121, 2019-The purpose of this study was to compare the longitudinal effects of 6 weeks of rest-pause vs. traditional multiple-set resistance training (RT) on muscle strength, hypertrophy, localized muscular endurance, and body composition in trained subjects. Eighteen trained subjects (mean ± SD; age = 30.2 ± 6.6 years; weight = 74.8 ± 17.2 kg; height = 171.4 ± 10.3 cm) were randomly assigned to either a traditional multiple-set group (n = 9; 7 men and 2 women; 3 sets of 6 repetitions with 80% of 1-repetition maximum (1RM) and 2-minute rest intervals between sets) or a rest-pause group (n = 9; 7 men and 2 women). The results showed no significant differences (p > 0.05) between groups in 1RM strength (rest-pause: 16 ± 11% for bench press, 25 ± 17% for leg press and 16 ± 10% for biceps curl vs. traditional multiple-set: 10 ± 21% for BP, 30 ± 20% for LP and 21 ± 20% for BC). In localized muscular endurance, the rest-pause group displayed significantly greater (p < 0.05) repetitions, only for the LP exercise (rest pause: 27 ± 8% vs. traditional multiple-set: 8 ± 2%). In muscle hypertrophy, the rest-pause group displayed significantly greater (p < 0.05) thickness, only for the thigh (rest-pause: 11 ± 14% vs. traditional multiple-set: 1 ± 7%). In conclusion, RT performed with the rest-pause method resulted in similar gains in muscle strength as traditional multiple-set training. However, the rest-pause method resulted in greater gains in localized muscular endurance and hypertrophy for the thigh musculature.

Bogdanis, GC, Tsoukos, A, Kaloheri, O, Terzis, G, Veligekas, P, and Brown, LE. Comparison between unilateral and bilateral plyometric training on single- and double-leg jumping performance and strength. J Strength Cond Res 33(3): 633-640, 2019-This study compared the effects of unilateral and bilateral plyometric training on single- and double-leg jumping performance, maximal strength, and rate of force development (RFD). Fifteen moderately trained subjects were randomly assigned to either a unilateral (U, n = 7) or bilateral group (B, n = 8). Both groups performed maximal effort plyometric leg exercises 2 times per week for 6 weeks. The B group performed all exercises with both legs, whereas the U group performed half the repetitions with each leg, so that total exercise volume was the same. Jumping performance was assessed by countermovement jumps (CMJs) and drop jumps (DJs), whereas maximal isometric leg press strength and RFD were measured before and after training for each leg separately and both legs together. Countermovement jump improvement with both legs was not significantly different between U (12.1 ± 7.2%) and B (11.0 ± 5.5%) groups. However, the sum of right- and left-leg CMJ only improved in the U group (19.0 ± 7.1%, p < 0.001) and was unchanged in the B group (3.4 ± 8.4%, p = 0.80). Maximal isometric leg press force with both legs was increased similarly between groups (B: 20.1 ± 6.5%, U: 19.9 ± 6.2%). However, the sum of right- and left-leg maximal force increased more in U compared with B group (23.8 ± 9.1% vs. 11.9 ± 6.2%, p = 0.009, respectively). Similarly, the sum of right- and left-leg RFD0-50 and RFD0-100 were improved only in the U group (34-36%, p < 0.01). Unilateral plyometric training was more effective at increasing both single- and double-leg jumping performance, isometric leg press maximal force, and RFD when compared with bilateral training.

La potenciación post-activación (PPA) ha demostrado ser una estrategia efectiva para incrementar el rendimiento de actividades de fuerza explosiva posteriores. El objetivo del presente trabajo fue revisar la literatura científica para conocer la metodología más efectiva en la obtención de PPA en el salto vertical. Se llevó a cabo una revisión en Medline, Scielo y SportDiscus hasta el 30 de Junio de 2018. Fueron mantenidas las directrices para el diseño de revisiones establecidas por PRISMA. La revisión localizó 37 estudios (n=659). La investigación disponible sugiere que la PPA puede obtenerse aplicando diferentes metodologías, siempre y cuando se respeten las dosis adecuadas de los parámetros: a) tipo de ejercicio y medio utilizado; b) intensidad y volumen del esfuerzo; c) descanso post-esfuerzo. La adecuada manipulación de estas variables permitirá incrementar el rendimiento explosivo en sujetos entrenados. No obstante, futuras investigaciones son necesarias para establecer una metodología que permita obtener PPA en menor tiempo y con mayor duración de sus efectos. Summary: Post-activation potentiation (PPA) has been demonstrated to be effective to increase performance subsequent activities on explosive force. The aim of this study was to review the scientific literature to determine the most effective methodology to obtain PPA in vertical jump. We conducted a review in Medline, Scielo, SportDiscus and Google Scholar up to June 30, 2018. The design guidelines were obtained from PRISMA for reviews. The review of works pinpointed 37 studies (n = 659). The available research suggests that PPA can be obtained by applying different methodologies, as long as the appropriate doses of the parameters are respected: a) type of exercise and tools used; b) intensity and volume of effort; c) rest post effort. Proper design of these variables will increase the explosive performance in trained subjects. However, further research is needed to establish a methodology to achieve PPA in less time and with greater duration of its effects.

This study examined the effects of listening to different music tempos during warm-up on short-term maximal performance and psychological responses, as a function of times of day (TOD).Fifteen well trained subjects (93.75% were semi-professional soccer players) randomly performed the 30-s continuous jump test (CJinf30/inf) for three morning sessions (07h00) and three evening sessions (17h00), separated by 48h of recovery, each after a warm-up under three different conditions: without music (NO-M), with music at 60 bpm (LOW-M), and with music at 120-140 bpm (HIGH-M). The maximal jump height (Hinfmax/inf), mean jump height of all jumps (Hinfmean/inf), and fatigue index (FI %) were measured during CJinf30/inf. Feeling states (FS) were determined after warm-up, and body temperature was controlled before/after warm-up, as well as after CJinf30/inf.Data analysis showed that Hinfmax/inf, Hinfmean/inf, and body temperature were higher at 17h00 than 07h00 in all experimental conditions. Moreover, Hinfmax/inf, Hinfmean/infand FS were better after warm-ups with LOW-M and HIGH-M compared to NO-M condition at both TOD, with a higher gain at 07h00. More importantly, Hinfmax/inf, Hinfmean/infand FS were better after warm-up with HIGH-M than with LOW-M at both TOD, with a higher gain at 07h00.Although both music tempos were beneficial, warming-up with high music tempo (120-140 bpm) is better than warming-up with low music tempo (60 bpm) for improving short-term maximal performance and psychological responses whatever the TOD, especially in the morning hours.

Given the wide variety of conditioning program trainings employed, the present study compared the catabolic effects induced by CrossFit&reg, and resistance training in moderately trained subjects. Twenty males joined either the CrossFit&reg, group (n = 10, 30 min/day of &ldquo, workout of the day&rdquo, ) or the resistance training (RT) group (n = 10, 30 min/day of resistance exercises) thrice a week, for 8 weeks. Salivary levels of cortisol, interleukin 1-beta (IL-1&beta, ), and uric acid were assessed via enzyme-linked immunosorbent assays before (PRE) and 30-min after (POST) SESSION 1 and SESSION 24. Variables&rsquo, percentual changes were computed as (POST-PRE)/PRE*100 in each session (&Delta, %). CrossFit&reg, acutely increased cortisol levels in both sessions, with a significant decrease in &Delta, %cortisol from SESSION 1 to 24. In the RT group, cortisol values decreased in both sessions, only acutely. A significant decrease in IL-1&beta, levels was registered acutely in both groups, in both sessions, whereas &Delta, %IL-1&beta, was not different between the two groups. While uric acid levels increased in both groups acutely, a chronic downregulation of &Delta, %uric acid, from SESSION 1 to 24, was appreciated for the RT group only. Overall, CrossFit&reg, appeared to induce more intense effects than the RT program as to the investigated catabolic responses.

BACKGROUND The primary purpose of this study was to measure the acute effects on muscle thickness, arm circumference, and peak force between unilateral seated row and unilateral biceps curl exercises for elbow flexors after a RT session in recreationally-trained subjects. METHODS Fourteen resistance-trained men (25.3±2.5years, 76.5±6.4kg, 174.6±7cm) performed 6 sets of 10RM and 2-min rest for one of two exercises (unilateral seated row exercise, USR or unilateral biceps curl, UBC). Muscle thickness (MT), arm circumference (AC), and peak force (PF) were measured before 10-min (control), pre-RT session and post-RT (immediately after, 15-min and 30-min). All acute RT variables were measured during both exercises: maximal number of repetitions (MNR), total number of repetitions (TNR), time under tension (TUT), rating of perceived exertion (RPE). Two-way ANOVAs were used to test differences between exercises and moments with an alpha of 5%. RESULTS For PF, there was a significant difference between pre- and post-0 for UBC and USR (P

Despite discrepant phenotypes, the insulin resistant (IR) and trained states have high levels of intramyocellular lipid. We hypothesize that higher muscle lipid turnover in the trained state may explain this discrepancy. Obese, IR subjects and trained subjects were fasted overnight (Table1). To characterize muscle lipid turnover, we conducted a pulse-chase experiment using sequential [U-13C]palmitate and [9-2H]palmitate infusions (6 h each) with a 1 hour overlap to label endogenous and exogenous FFA pools. Biopsy#1 (Bx#1 -s/p 14 hr fast) was performed at the time of the overlap (last hour of the 6 h [U-13C]palmitate infusion, after 1 h of starting the [9-2H]palmitate). Bx#2 was performed at the study conclusion (last hour of the [9-2H]palmitate infusion-s/p 20 hr fast). Plasma and muscle samples were analyzed for palmitate enrichment and concentration. Regardless of phenotype, muscle triglyceride (IMTG) synthesis at Bx#1 was not different as assessed by either [U-13C]palmitate or [9-2H]palmitate; IMTG synthesis assessed by [9-2H]palmitate was 9-fold higher than [U-13C]palmitate. At Bx#2, IMTG breakdown as assessed by [U-13C]palmitate was similar between groups, whereas [9-2H]palmitate showed IMTG synthesis in the obese, IR group and IMTG breakdown in the trained group. IMTG synthesis was higher with recent (1 hour) FFA exposure than more prolonged (6 hour) FFA exposure supporting separate FFA pools in lipid utilization. Disclosure L.S. Chow: None. D.G. Mashek: None. M.D. Jensen: None. Funding National Institutes of Health (R01DK098203, UL1TR000114)

Background: In order to stay safe, and to successfully complete their work, firefighters have to constantly assess and process large numbers of sensory stimuli and adapt to the inherent risks present in the working environment. Objective: The purposes of the present preliminary study were to analyse the speed of Reaction Time responses (RT) of Italian Firefighters and to compare their cognitive responses with non-firefighting subjects. Methods: Anthropometric (weight, height and BMI) and RT (time-to-completion –TTC-, mean of reaction time –MRT-, and errors made -E-) evaluations were administered at 16 volunteers (Age: 40.3 ± 6.7 yrs; BMI: 23.8 ± 2.3 kg/m2) divided in Firefighters (FG) and Control (CG) groups. RT test consisted of 3 trials (T1 = 1s of stimulus duration and 1s interval between stimulus and the other; T2 = 0.5s of stimulus duration and 1s interval between stimulus and the other; T3 = 0.5s of stimulus duration and 0.5s interval between stimulus and the other). Mann Whitney U test between groups was applied to asses differences (p ≤ 0.05) in TTC, MRT, and E while Friedmann test and Dunn-Sidak post hoc were used to evaluate significant differences in the 3 trials in each variable of each group. Results: No significant differences based on anthropometric parameters were observed between groups. Despite no significant differences emerged for TTC and MRT between groups, we observed significant differences in E between groups (CG = 4; FG =12) and in the 3rd condition in each variable of each group. Conclusion: Workout programs that integrate reaction time training with job performance should be created to increase job performance.

This study aimed to investigate the potential effects of acute soccer matches performed in morning, afternoon and at night on both nesfatin-1 and irisin levels in trained subjects. Total of 20 male subjects performed in soccer matches at three different times of day: morning, afternoon, and night. Pre- and post-match venous blood samples were taken, and levels of both nesfatin-1 and irisin were analysed using the enzyme-linked immunosorbent assay (ELISA). Following all matches, the subjects' irisin levels increased significantly in all subjects (p < 0.0001). Nesfatin-1 levels were also increased after the matches; however, the increase was statistically significant for morning (P=0.01) and night-time (p=0.009). The subjects' nesfatin-1 levels did not increase in all subjects and decrease of nesfatin-1 levels observed in some subjects after matches. This study finds that soccer matches performed different workout times have strong stimulatory effects on irisin levels in all subjects but nesfatin-1 response varied among the subjects and it did not change significantly in afternoon match.

Objective: The aim of this study was to examine the effect of eccentric isotonic training on hamstring flexibility and eccentric and concentric isokinetic peak torque in trained and untrained subjects. Methods: Sixty healthy subjects (mean age: 21.66 ± 2.64) were divided into three equal groups, each with 20 voluntary participants. Two experimental groups (untrained and trained groups) participated in a hamstring eccentric isotonic strengthening program (five days/week) for a six-week period and one control group that was not involved in the training program. The passive knee extension range of motion and hamstring eccentric and concentric isokinetic peak torque were measured at angular velocities 60° and 120°/s for all groups before and after the training period. Results: Two-way analysis of variance showed that there was a significant increase in the hamstring flexibility of the untrained and trained groups (25.65 ± 6.32°, 26.55 ± 5.99°, respectively), (p 0.05). Moreover, there was a significant increase in eccentric isokinetic peak torque of both the untrained and trained groups (127.25 ± 22.60Nm, 139.65 ± 19.15Nm, 125.40 ± 21.61Nm, 130.90 ± 18.71Nm, respectively), (p 0.05) at both angular velocities. On the other hand, there was no significant increase in the concentric isokinetic peak torque of the three groups (92.50 ± 20.50Nm, 79.05 ± 18.95Nm, 92.20 ± 21.96Nm, 79.85 ± 18.97Nm, 100.45 ± 25.78Nm, 83.40 ± 23.73Nm, respectively), (p > 0.05) at both angular velocities. The change scores in the hamstring flexibility (06.25 ± 1.86°) and eccentric peak torque of the untrained group (16.60 ± 4.81Nm, 17.45 ± 5.40Nm, respectively) were significantly higher (p 0.05). Conclusion: After a six-week period of eccentric isotonic training, the hamstring eccentric peak torque and flexibility of trained and untrained groups improved without changes in the concentric peak torque. Moreover, the improvement of untrained subjects was higher than trained subjects. These findings may be helpful in designing the hamstring rehabilitation program. Keywords: Eccentric exercise, Extensibility, Hamstring, Muscle torque, Trained subjects

Informed consent usually provides foreknowledge of experimental methods that can potentially increase expectation of stimuli and, therefore, influence the response. We determined the effects of increased expectation and trip-specific training on the recovery response following a treadmill-delivered, trip-specific disturbance. To deliver unexpected disturbances, subjects were deceived during the informed consent process. The primary hypothesis was that the recovery response following an expected postural disturbance would be characterized by trunk kinematics that have been shown to decrease the likelihood of a fall, compared to following an unexpected postural disturbance. We further hypothesized that following an unexpected postural disturbance, the recovery response of the subjects who had completed a trip-specific training protocol would be more biomechanically favorable to recovery compared to those of subjects who had not received the training.Young adults were randomized into Untrained or Trained groups. During the informed consent process, the purpose of the study was explained to subjects in both groups as being to determine the effect of trip-specific training on postural sway while performing an attention-demanding task. Untrained subjects completed two trials during which they minimized their postural sway. During the second trial, an unexpected disturbance was delivered while they performed the attention-demanding task. Trained subjects performed a pre-training postural sway trial, followed by the delivery of a series of expected, training disturbances. Finally, an unexpected disturbance was delivered while they minimized postural sway and performed the attention-demanding task.Expectation significantly improved trunk kinematics (p .05). In addition, participation in the trip-specific training protocol following the unexpected disturbance the trunk kinematics of the Trained subjects were more biomechanically favorable to recovery than those of the Untrained subjects (p .01).Improved trunk kinematics following trip-specific training may be independent of the extent to which the disturbance is expected.

In a group of 44 healthy trained subjects (biathlon athletes), age- and sex-related peculiarities of the results of an H-reflex study were examined (EMG responses were recorded from the m. soleus). Tested subjects were divided into four groups, women and men, juniors (younger than 20 years), and adults (20–30 years). The measured indices in the groups of men and women demonstrated certain significant differences; these differences were greater in adults. Thresholds for generation of the H- and M-responses were higher in females as compared to those in males. Amplitudes of the maximum H- and M-responses in men (in both juniors and adults) significantly exceeded the analogous values in women. In adult sportsmen, amplitudes of the M-responses were higher, while ratios of the maximum H- and M-responses were smaller than those in juniors. Probable reasons of gender- and age-related peculiarities of the H-reflex indices are discussed.

International audience; This study explored the impact of perceptual interactions on the odor intensity of 222 binary mixtures designed from 72 odorants found in food products. Odor intensity was rated by 30 trained subjects. The results showed that in most cases, the components' odor was perceived within the mixture and their intensity remained the same as in the unmixed situation in 54.3% of cases. Masking was the second major effect (44.8%) and occurred more frequently when components' pleasantness was significantly different. Synergy occurred in a small number of cases (0.9%) and only for four compounds. The overall odor intensity of the mixture was determined to be equal to the strongest component in most cases (73.9%), while partial addition was observed as the second most frequent effect (21.7%), especially when the components had equal intensity. Overall, this work provides general rules about the outcome to expect when mixing key components of food aromas.

Raman spectroscopy is a rapid and non-destructive technique suitable for biological fluids analysis. In this work, dispersive Raman spectroscopy has been employed as a rapid and nondestructive technique to detect the metabolites in urine of physically active subjects before and after vigorous 30min pedaling or running compared to sedentary subjects. For so, urine samples from 9 subjects were obtained before and immediately after physical activities and submitted to Raman spectroscopy (830nm excitation, 250mW laser power, 20s integration time) and compared to urine from 5 sedentary subjects. The Raman spectra of urine from sedentary showed peaks related to urea, creatinine, ketone bodies, phosphate and other nitrogenous compounds. These metabolic biomarkers presented peaks with different intensities in the urine of physically active individuals after exercises compared to before, measured by the intensity of selected peaks the Raman spectra, which means different concentrations after training. These peaks presented different intensity values for each subject before physical activity, also behaving differently compared to the post-training: some subjects presented increase while others decrease the intensity. Raman spectroscopy may allow the development of a rapid and non-destructive test for metabolic evaluation of the physical training in active and trained subjects using urine samples, allowing nutrition adjustment with the sport's performance.

Clinical Scenario: Manipulation of exercise variables in resistance training (RT) is an important component in the development of muscular strength, power, and hypertrophy. Currently, most research centers on untrained or recreationally trained subjects. This critically appraised topic focuses on studies that center on the well-trained subject with regard to frequency of training. Clinical Question: In well-trained male subjects, is there an association between RT frequency and the development of muscular strength and hypertrophy? Summary of Key Findings: Four studies met the inclusion criteria and were included for analysis. All studies showed that lower-frequency training could elicit muscular strength and hypertrophy increases. One study suggested that a higher frequency compared with a lower frequency may provide a slight benefit to hypertrophic development. One study reported a greater level of delayed onset muscle soreness with lower frequency training. The 4 studies demonstrate support for the clinical question. Clinical Bottom Line: Current evidence suggests that lower-frequency RT produces equal to greater improvements on muscular strength and hypertrophy in comparison to higher-frequency RT when volume is equated. The evidence is particularly convincing when lower-frequency RT is associated with a total-body training protocol in well-trained male subjects. Strength of Recommendation: There is moderate-to-strong evidence to suggest that lower-frequency RT, when volume is equated, will produce equal to greater improvements on muscular strength and hypertrophy in comparison to higher-frequency RT.

The aim of this study was to compare the acute effects of performing half squats (HSs) with different loading intensities (1, 3, and 5 repetitions maximum [RM], and 60% 1RM) and a different number of sets (1, 2, and 3) on the countermovement jump (CMJ) performance of 18 highly-trained male subjects. Participants were submitted to four experimental conditions (1RM, 3RM, 5RM, and 60% 1RM) in randomized order. The CMJ was assessed before and after each set. Differences in CMJ performance between the distinct experimental conditions and individual responses in CMJ performance induced by the different protocols were analyzed via the magnitude-based inference method. Overall, significant improvements were detected in individual CMJ heights after each activation protocol. It can be concluded that the use of 1 to 3 sets of HSs performed at moderate-to-high loads may be an effective strategy to improve jump performance in highly-trained subjects. Nevertheless, despite the high efficiency of the protocols tested here, coaches and researchers are strongly encouraged to perform individualized assessments within the proposed range of loads and sets, to find optimal and tailored post-activation potentiation protocols.

Detecting subtle lesions in mammograms indicative of early breast cancer usually requires years of experience. Well-designed training paradigms could be a strong tool for promoting perceptual learning (PL) with rapid and long-lasting improvement in detectability of these subtle mammographic lesions. Given that PL occurs without feedback about the accuracy of subjects’ responses, the role of feedback has been completely ignored in clinical applications of PL. However, in this study, we found that the contents of the feedback profoundly and differentially influence the formation and retention of PL to detect calcification and architectural distortion lesions, two types of mammographic lesions that are frequently missed in mammographic screenings. We trained subjects to detect one type of lesion in a mammogram and manipulated the content of the response feedback during training for 3 groups (no feedback, correctness only, and both correctness and location of the lesion). We found that PL occurred for both lesions when both correctness and location feedback were provided. PL also occurred for calcifications but not for distortions when only correctness was provided. No learning occurred without feedback for either lesion. A retest conducted six months later showed that PL was retained only in the group with both correctness and location feedback for both types of lesions. In contrast to the general consensus of basic PL studies, our results demonstrate that the content of the response feedback is a determining factor in forming and retaining PL to detect mammographic lesions.

Marchetti, PH, Magalhaes, RA, Gomes, WA, da Silva, JJ, Stecyk, SD, and Whiting, WC. Different knee and ankle positions affect force and muscle activation during prone leg curl in trained subjects. J Strength Cond Res XX(X): 000-000, 2019-Different joint positions for biarticular muscles may affect force and muscular activity during single-joint exercises. The aim of this study was to compare the maximal isometric contractions and muscle activation in 2 different knee and ankle positions during prone leg curl exercise in trained subjects. Fifteen resistance-trained men (27 ± 4 years, 178.80 ± 5.72 cm, 86.87 ± 12.51 kg) were recruited. The peak force (PF) and muscle activation of biceps femoris, gastrocnemius lateralis (GL), and soleus lateralis (SL) were measured during knee flexion at 0 and 90° and maximal dorsiflexion (D) or plantarflexion (P). Three maximal voluntary isometric contractions of 5 seconds were performed for each combination of knee and ankle positions. Two-way repeated-measures analysis of variances were used for all dependent variables. For PF, there was a significant difference between ankle positions (D × P) at 90° (p = 0.009) and knee positions (0 × 90°) for D (p < 0.001) and P (p < 0.001). Peak force was greater with the knee at 0° and the ankle maximally dorsiflexed. For GL, there was a significant difference between ankle (D × P) at 0° (p = 0.002) and knee positions (0 × 90°) for D (p = 0.005). Gastrocnemius lateralis activation was greater with the knee at 90° of flexion and the ankle maximally dorsiflexed. For SL, there was a significant difference between ankle positions (D × P): at 90° (p = 0.001) and at 0° (p = 0.002). Soleus lateralis is more active in plantarflexion irrespective of the knee joint position. Isometric contractions with full knee extension produce more strength regardless of the ankle position; neither the knee position nor the ankle position may influence the activity of the hamstrings.

The manipulation of the volume and intensity of static stretching (SS) can affect the range of motion (ROM) and muscle force output. The purpose of this study was to investigate the effect of two different SS protocols with different intensities (50% and 85% POD) and volumes (120-s and 240-s) on ROM, peak force, and muscle activity during maximal isometric leg curl exercise in well-trained participants. Fifteen young males (age:27.5 ± 6.1years, height:175.6 ± 4.7cm, and body mass:81.5 ± 10.4kg, 6 ± 2 years of resistance training experience) performed passive hip flexion with two different SS protocols: six stretches of 40-s, with 15-sec rest between each stretch at 50% of the point of discomfort (POD) and three stretches of 40-s, with 15-sec rest between each stretch at 85%POD. The passive hip flexion ROM, biceps femoris muscle activation (integrated electromyography: IEMG), and knee flexors force were monitored during a 3-s maximal voluntary isometric leg curl exercise. ROM increased between pre- and post-intervention for both SS protocols (50%POD

Lambert, C, Beck, BR, and Weeks, BK. Landing impact intensities for jumping exercises from the OPTIMA-Ex trial in trained and untrained women. J Strength Cond Res 35(9): 2504-2510, 2021-High-intensity mechanical loads are required to elicit a positive adaptive bone response. Our aim was to quantify the mechanical loads of impact exercises used in each progressive stage of a bone-targeted exercise intervention (the OPTIMA-Ex trial) and to investigate differences in mechanical loads between untrained and trained subjects. A randomized repeated measures experimental design was used to quantify and compare the mechanical loads, including vertical ground reaction force (vGRF) and the rate of loading (RoL) of the landing phase, of all impact exercises applied in the OPTIMA-Ex trial and to determine the load intensity for each training stage of the impact intervention. Fifteen healthy young adult women aged 18-30 years (mean 23.1 ± 3.5 years) were recruited (5 trained and 10 untrained). Overall, vGRF was classified as high impact (>4 times body mass [BM]) for all 7 training stages (4.70 ± 1.89 to 6.79 ± 2.17 BM), whereas RoL ranged from 207.01 ± 175.09 to 371.52 ± 393.43 BM·s-1 across the stages. Furthermore, a significant time effect was observed between training stages for vGRF/BM (p = 0.001) and RoL (p < 0.001). Trained subjects exhibited greater impact loads than untrained subjects for activities at every training stage (p < 0.01). We found that impact activities at every stage of the OPTIMA-Ex trial not only met the GRF criteria for high intensity but also exhibited progressive increases in load for successive stages. Furthermore, trained subjects were capable of producing greater impact loads than untrained subjects.

The capacity and reliability of biological memory could be exceeded by a constantly growing flux of information to remember and operate by. Yet, our memory is fragile and could be easily impaired, and the prevalence of memory disorders is increasing in correlation with the population’s mean age. As expected, auxiliary memory devices (such as writing pads and computers) are abundant but are operated indirectly using significant effort compared with biological memory. We report a working prototype of a simplified, 4 KB random-access memory (RAM) that can be written to or read from using thought and could be embedded more seamlessly than other artificial memory aids. The system analyses EEG signals to extract attention levels, which trained subjects can use to write messages into an RFID sticker, or read from it on a display. We describe basic modes of using memory by a single subject, emulate common forms of social communication using this system, and highlight new forms of social usage and allocation of memories that are linked to specific persons. This preliminary prototype highlights the technical feasibility and the possibilities of implantable thought-operated memory devices and could be developed further to provide seamless aid to people suffering from memory disorders in the near future.

This study analyzed the relationship between CrossFit performance and power and strength variables measured in the full-squat exercise. Twenty male trained subjects (33±7 years) performed an incremental load full-squat test for assessment of the 1-repetition maximum (1RM) and the mean (Pmean) and peak (Ppeak) power. Performance in 5 different Workouts of the Day (WODs) was measured on different days, and overall CrossFit performance was determined as the sum of the scores obtained in these WODs. Athletes were then assigned to a high (HP) or low (LP) performance group based on the median score for overall performance. Correlation analysis between squat variables and performance was performed and between-group differences were assessed. Moderate to strong (r=0.47–0.69, p

Summary Objective To assess and quantify singers’ strategies for adding air to phonation to sound “breathy” in a healthy manner Study design Case-control study with 20 professional singers. Methods Twenty singers were recorded performing sustained vowels in the Complete Vocal Technique Neutral vocal mode with and without audible air added to the voice by means of laryngostroboscopic imaging using a videonasoendoscopic camera system, electroglottography, long-term average spectrum, as well as acoustic signals and audio perception. Singers completed Voice Handicap Index and Reflux Symptom Index questionnaires prior to examination. Results Air added to the voice resulted in an expected glottal gap along the length of the vocal folds, with little to no further difference in the supraglottic area, as compared with the Neutral phonation. Air added resulted in lowered Qx, mean Sound Pressure Level, and Cepstral Peak Prominence, but higher Harmonics-to-Noise Ratio, Jitter, and Shimmer, with decreased energy at the fundamental frequency. Adding audible air to the phonation did not exhibit similar effects on acoustics for males and females. Also, for females, H1–H2 difference decreased with air added, while it increased for males. Conclusion Singers produce an audible airy phonation similar yet significantly different to the breathy phonation reported for both healthy and pathological speakers.

The aim of this study was to determine if exercise time trials (TT) of different durations would cause different levels of peripheral and central fatigue during exercise.Twelve trained subjects (11 men, one woman) performed TT lasting 3, 10, and 40 min with repetitive self-paced concentric right knee extension at 60°·s on an isokinetic dynamometer. Neuromuscular function was assessed before, during, and immediately after the TT using voluntary and electrically evoked forces.Maximal voluntary contraction force, evoked peak force for single stimulus, and rating of perceived exertion reached similar levels at termination of all TT. Evoked peak force for paired stimuli of 100 Hz decreased more for the 40-min TT compared with the 3-min TT (-42% ± 15% vs -37% ± 13%, P0.05), and central fatigue was significant for the 40-min TT and 10-min TT but not for the 3-min TT. Single stimulus and paired stimuli of 100 Hz decreased, whereas voluntary electromyography normalized to M-wave for self-paced contractions increased during the end-spurt in all TT.These data demonstrate that the extent of peripheral and central fatigue that contribute to reductions in force of single-limb dynamic contractions depend on the duration and intensity of self-paced exercise. There was no evidence for a critical threshold in peripheral fatigue that was common to all TT.

The purpose of this study was to examine the effect of time of day on visuospatial attention in trained subjects. We used the line-bisecting task. The protocol involved 30 healthy volunteer female soccer players (age: 21.1 ± 2.1 years, level of experience: 8.1 ± 3.2 years, height: 1.7 ± 0.03 cm, weight: 59.2 ± 3.49 kg). They performed two-test sessions at different times of day, 8:00 am and 8:00 pm. The results showed a significant time-of-day effect on line-bisecting performance, with a better precision in the evening than in the morning. The rightward error observed in the morning was reversed in the evening. An interaction between time of day x length was also observed, indicating that the difference in performance between the morning and the evening increased with the length of the line. We conclude that activities that require better visuospatial performance should be programed to take place in the evening.

Load carriage is a necessary burden for tactical athletes. A combination of training modes, including aerobic conditioning and progressive load carriage, may lead to improved performance. The critical speed (CS) concept enables the practitioner to prescribe high-intensity interval training (HIIT) time limits (TLIMs) from a single 3-minute all-out exercise test (3 MT). We sought to examine the effect of a standard load carriage (18.86 kg) on CS and the finite running capacity > CS (D'). A group of trained subjects (age: 26 ± 5 years, height: 181 ± 4 cm, body mass [BM]: 90 ± 14 kg) completed a loaded and unloaded (UL) 3 MT. The CS was reduced by 0.66 ± 0.24 m·s (p < 0.01) in the loaded condition. There was a small nonsignificant increase in D' (21.25 ± 39.53 m, p = 0.07). The higher the % load carriage relative to BM is, the greater decline in CS (r = 0.83, p < 0.01). A revised CS with load carriage from the UL 3 MT may be calculated using: adjusted CS = original CS + ([-0.0638 × %load]) + 0.6982. Our results indicate that revised CS and TLIMs for fixed distance, fixed time, or fixed speed HIIT prescriptions may be derived from a UL 3 MT. Such calculations would enable more expeditious training for tactical athletes. We recommend further research involving implementation of HIIT using this new method.

Numerosas investigaciones centran su atención en el estudio de las capacidades físicas que componen la condición física y el análisis de las posibles diferencias que pueden existir según las diversas variables. El objetivo de esta investigación es conocer la tendencia en los resultados obtenidos por investigaciones publicadas en la literatura científica en relación a la existencia de diferencias en función de las variables sexo, entrenamiento y edad en las capacidades físicas, fundamentalmente en la fuerza. Por tanto, se ha realizado una revisión de los artículos publicados en revistas de ámbito científico a través de palabras clave como género, edad y nivel de actividad. Los resultados obtenidos señalan que la tendencia en los artículos consultados es que en cuanto a la fuerza evaluada, tanto a través de salto como de dinamometría manual, los sujetos varones, los entrenados y los de mayor edad, son los que obtienen mejores resultados. En cuanto a la flexibilidad las mujeres y los sujetos entrenados son los que poseen mejores resultados. En lo que se refiere a la velocidad y resistencia los varones y los sujetos entrenados son los que obtienen óptimos efectos.Abstract. Numerous investigations focus their attention on the study of physical abilities that make up fitness and analyzing the differences that may exist in terms of different variables. The objective of this research is to determine the trend in the published scientific literature regarding differences in terms of sex, age, and training in physical abilities, primarily in studies about strength. A review of articles published in different scientific journals was conducted using keywords such as gender, age and activity level. The results indicate that the trend in the articles is that regarding the strength assessed through both jump and manual dynamometry, the male subjects, the trained subjects and older subjects have better results. In terms of flexibility, females and subjects trained have better results. Finally in regards to speed and endurance , males and subjects trained have better results.

AIM the aim of this study was to analyze the weekly sets volume (WSV) performed by trained men and women for each muscle group in muscle hypertrophy programs. METHODS One hundred and five resistance training practitioners of both sex (42 women, 29.8±5.7 years; 63 men, 28.5±5.7 years) consented to the analysis of their current training programs. Their training plains were analyzed by a researcher that used the following equation to determine the WSV performed for each muscle group: "number of exercises per muscle group per training session X number of sets per exercise in each training session X weekly training frequency per muscle group". The median values ​​by each muscle group were compared within and between genders. RESULTS Between group analysis demonstrated that men performed higher WSV for upper body (UB) muscles than women (47.2±14,6 vs. 18.2±7.4 sets). Conversely, women performed a higher WSV for lower body (LB) muscle groups than men (23.8±11.2 vs. 11.5±7.0 sets). The training volume for the abdominal muscles did not differ between groups. When comparing the WSV for the UB, LB and core musculature within groups, men perform higher training volumes for the UB compared to the LB and core, while women train the LB with a higher volume compared to the other musculature. CONCLUSION For some muscle groups, the WSV is higher than recommended in the literature for muscle hypertrophy. Men emphasize the UB training, while women emphasize training the LB. Moreover, the WSV performed by subjects of both genders is disproportionate between different muscle groups.

A specific drop jumps (DJs) protocol (using 100 jumps) has been largely used to induce muscle damage. However, it failed to show relevant drop in performance in well-trained individuals. Trained subjects may require a protocol with greater volume to induce decrease of muscle performance. The aim of this study was to assess muscle performance after two DJs damaging protocols with different volumes in well-trained individuals. Eighteen strength and/or power-trained males (4.92 ± 2.78 years of training experience) were randomly assigned into one of two groups: DJ100 (five sets of 20 DJs) or DJ140 (seven sets of 20 DJs), with 2-min of rest interval. DJs were performed from a 60-cm box. After landing, the volunteers performed a maximal vertical rebound jump. Muscle swelling increased significantly on both DJ100 and DJ140 (p < 0.001). Maximal isometric torque (MIT) decreased significantly on both DJ100 (p = 0.005) and DJ140 (p < 0.001). MIT showed no between-group difference on pre-assessment (p = 0.815). However, on post-assessment, MIT was significantly lower on DJ140 than DJ100 (p = 0.043). Countermovement jump (CMJ) decreased significantly on DJ140 (p = 0.001), but not on DJ100 (p = 0.802). There was no between-group difference on pre-assessment (p = 0.978). However, on post-assessment, CMJ was significantly lower on DJ140 than DJ100 (p = 0.038). DJ140 induced greater drop in isometric strength than DJ100 and only DJ140 significantly reduced jump performance. These results demonstrated that well-trained individuals require a great volume of DJs to reduce substantially muscle performance. Resumo Um protocolo específico de Drop Jumps (DJs), com 100 saltos, tem sido amplamente utilizado para induzir o dano muscular. Entretanto, este protocolo tem falhado em mostrar uma queda relevante em indivíduos treinados. Objetivou-se avaliar o desempenho muscular após dois protocolos de DJs com diferentes volumes em indivíduos treinados. Dezoito homens treinados em força e/ou potência (4,92 ± 2,78 anos de treinamento) foram aleatoriamente designados em um dos dois grupos: DJ100 (cinco séries de 20 DJs) ou DJ140 (sete séries de 20 DJs), com 2 minutos entre as séries. Os DJs foram executados de uma caixa de 60 cm de altura. Após a aterrisagem, os voluntários executaram um salto vertical máximo. O inchaço muscular aumentou significativamente em ambos os grupos (p < 0,001). O torque isométrico máximo (TIM) reduziu significativamente tanto no DJ100 (p = 0,005) quanto no DJ140 (p < 0,001). O TIM não apresentou diferenças entre grupos no momento pré (p = 0,815). Entretanto, no momento pós, o TIM foi significativamente inferior no DJ140 em relação ao DJ100 (p = 0,043). O salto com contra movimento (SCM) reduziu significativamente no DJ140 (p = 0,001), mas não no DJ100 (p = 0,802). No momento pós, o SCM foi significativamente inferior no DJ140 em relação ao DJ100. O DJ140 induziu uma queda maior na força isométrica em relação do DJ100, e somente o DJ140 reduziu significativamente o desempenho no salto. Esses resultados demonstraram que indivíduos bem treinados requerem um grande volume DJs para reduzir substancialmente o desempenho muscular.

Performance was measured on seven common psychoacoustical tasks for about 75 highly trained subjects. Because some psychoacoustical outcomes varied by race, the subjects were partitioned into White and Non-White categories for analysis. Sex, race, and menstrual-cycle differences in performance are described in a companion paper [McFadden, Pasanen, Maloney, Leshikar, and Pho (2018). J. Acoust. Soc. Am. 143, 2338-2354]. Also measured for all subjects were three types of otoacoustic emissions (OAEs): spontaneous otoacoustic emissions (SOAEs), click-evoked otoacoustic emissions (CEOAEs), and distortion-product otoacoustic emissions (DPOAEs). The experimental question was whether and how OAEs were correlated with psychoacoustical performance. In accord with past findings, the SOAEs and CEOAEs exhibited substantial sex and race differences, but the DPOAEs did not. Somewhat surprisingly, the correlations between OAEs and psychoacoustical performance were generally weak. No form of OAE was highly correlated with any psychoacoustical task for both sexes within a race category. Thus, there was no compelling evidence that the mechanisms underlying OAEs also contribute systematically to performance in any of the simultaneous or temporal masking tasks studied here. Especially surprising were the weak correlations between OAEs and detection of a tone in the quiet. Apparently individual differences in psychoacoustical performance reside more in post-cochlear (neural) mechanisms than in individual differences in the cochlear ("mechanical") mechanisms underlying the OAEs measured here.

Harden, M, Wolf, A, Russell, M, Hicks, KM, French, D, and Howatson, G. An evaluation of supramaximally loaded eccentric leg press exercise. J Strength Cond Res 32(10): 2708-2714, 2018-High-intensity eccentric exercise is a potent stimulus for neuromuscular adaptation. A greater understanding of the mechanical stimuli afforded by this exercise will aid the prescription of future eccentric training regimens. This study sought to investigate the mechanical characteristics of supramaximally loaded eccentric exercise when using a custom-built leg press machine. Using a within-subject, repeated-measures design, 15 strength trained subjects (age, 31 ± 7 years; height, 180.0 ± 6.8 cm; body mass, 81.5 ± 13.9 kg) were assessed under 3 different conditions: low (LO), moderate (MOD), and high (HI) intensity, which were equivalent in intensity to 110, 130, and 150%, respectively, of peak force during an isometric maximal voluntary contraction (IMVC) performed on leg press at 90° knee flexion. All loading conditions demonstrated a similar pattern of mechanical profile; however, the variables underpinning each profile showed significant (p < 0.01) load-dependent response (LO vs. MOD, MOD vs. HI, LO vs. HI) for all variables, except for average acceleration. Average force associated with each loading conditions exceeded IMVC but equated to a lower intensity than what was prescribed. Repetitions under higher relative load intensity stimulated greater average force output, faster descent velocity, greater magnitude of acceleration, shorter time under tension, and a decline in force output at the end range of motion. This research provides new data regarding the fundamental mechanical characteristics underpinning supramaximally loaded eccentric leg press exercise. The information gathered in the study provides a foundation for practitioners to consider when devising loading strategies and implementing or evaluating supramaximally loaded eccentric exercise when using a similar exercise and device.

The changes in hemoglobin (Hb) profile following autologous blood transfusion (ABT) for the first time were studied for anti-doping purposes. Twenty-four healthy, trained male subjects (aged 18‒40) were enrolled and randomized into either the transfusion (T) or control (C) groups. Blood samples were taken from the T subjects at baseline, after withdrawal and reinfusion of 450 ml of refrigerated or cryopreserved blood, and from C subjects at the same time points. Hematological variables (Complete blood count, Reticulocytes, Immature Reticulocytes Fraction, Red-cell Distribution Width, OFF-hr score) were measured. The Hb types were analyzed by high-performance liquid chromatography and the Hemoglobin Profile Index (HbPI) arbitrarily calculated. Between-group differences were observed for red blood cells and reticulocytes. Unlike C, the T group, after withdrawal and reinfusion, showed a significant trend analysis for both hematological variables (Hemoglobin concentration, reticulocytes, OFF-hr score) and Hb types (glycated hemoglobin-HbA1c, HbPI). The control charts highlighted samples with abnormal values (> 3-SD above/below the population mean) after reinfusion for hematological variables in one subject versus five subjects for HbA1c and HbPI. A significant ROC-curve analysis (area = 0.649, p = 0.015) identified a HbA1c cut-off value ≤ 2.7% associated to 100% specificity of blood reinfusion (sensitivity 25%). Hemoglobin profile changed in trained subjects after ABT, with abnormal values of HbA1c and HbPI in 42% of subjects after reinfusion. Future studies will confirm the usefulness of these biomarkers in the anti-doping field.

Background The aim of this study was to assess the accuracy of three different sport watches in estimating energy expenditure during aerobic and anaerobic running. Methods Twenty trained subjects ran at different intensities while wearing three commercial sport watches (Suunto Ambit2, Garmin Forerunner920XT, and Polar V800). Indirect calorimetry was used as the criterion measure for assessing energy expenditure. Different formulas were applied to compute energy expenditure from the gas exchange values for aerobic and anaerobic running. Results The accuracy of the energy expenditure estimations was intensity-dependent for all tested watches. During aerobic running (4–11 km/h), mean absolute percentage error values of −25.16% to +38.09% were observed, with the Polar V800 performing most accurately (stage 1: −12.20%, stage 2: −3.61%, and stage 3: −4.29%). The Garmin Forerunner920XT significantly underestimated energy expenditure during the slowest stage (stage 1: −25.16%), whereas, the Suunto Ambit2 significantly overestimated energy expenditure during the two slowest stages (stage 1: 38.09%, stage 2: 36.29%). During anaerobic running (14–17 km/h), all three watches significantly underestimated energy expenditure by −21.62% to −49.30%. Therefore, the error in estimating energy expenditure systematically increased as the anaerobic running speed increased. Conclusions To estimate energy expenditure during aerobic running, the Polar V800 is recommended. By contrast, the other two watches either significantly overestimated or underestimated energy expenditure during most running intensities. The energy expenditure estimations generated during anaerobic exercises revealed large measurement errors in all tested sport watches. Therefore, the algorithms for estimating energy expenditure during intense activities must be improved before they can be used to monitor energy expenditure during high-intensity physical activities., BMC Sports Science, Medicine and Rehabilitation, 9 (1), ISSN:2052-1847

Physical exercise influences the body's oxidative status. The modifications can involve lipids, proteins and nucleic acids, and different effects seem to be induced by regular and acute exercise respectively. We examined protein oxidation, expressed as concentration of protein carbonyl groups (PC), in trained subjects before (time 0), 10 min (time 1) and 24 hours (time 2) after a cardiopulmonary test performed on a cycloergometer. We enrolled 38 trained subjects (26 men and 12 women), subdivided in two groups (A1 and B1) of 19 subjects each, according to the median value of VO2max, and in two groups (A2 and B2) of 19 subjects each, according to the median value of PC at baseline. PC concentration was measured by an enzyme-linked immunosorbent assay (ELISA). The groups A1 and B1 did not differ from each other as regards the basal PC level and groups A2 and B2 were not different as regards the VO2max. At time 1 PC showed a significant increase in comparison with baseline in trained subjects as a whole group, as well as in each subgroup. At time 2, PC were decreased in comparison with both times 0 and 1 in the whole group and in subgroups A1 and B2, whereas in subgroups A2 and B1 the PC value at time 2 was not different compared to time 0. The percentage increase of PC at time 1 vs time 0, as well as the percentage decrease at time 2 vs time 1 and time 0 respectively, were not different between subgroups A1 and B1. On the contrary, the percentage variations observed at each interval were significantly different between subgroups A2 and B2. The results suggest a reaction of antioxidant systems to acute exercise in trained subjects, influenced by basal PC levels more than by aerobic fitness.