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1.
J Strength Cond Res ; 27(11): 3116-31, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23736782

RESUMO

We sought to determine if hypertrophic training with intraset rest intervals (ISRs) produced greater gains in power compared with traditional rest (TRD) hypertrophic training. Twenty-two men (age 25 ± 5 years, height 179.71 ± 5.04 cm, weight 82.1 ± 10.6 kg, 6.5 ± 4.5 years of training) matched according to baseline characteristics were assigned to 12 weeks of training using TRD or ISR. Body composition, strength (1-repetition maximum [1RM] bench and squat), and power output (60% 1RM bench and squat, and vertical jump) were assessed at baseline, 4, 8, and 12 weeks. Determination of myosin heavy chain (MHC) percentage from the vastus lateralis was performed pretraining and posttraining. Body composition was analyzed by analysis of variance, whereas performance measures and MHC were analyzed by analysis of covariance with baseline values as the covariate. Data are presented as mean ± SD changes pre to post. The ISR produced greater power output in bench (TRD 32.8 ± 53.4 W; ISR 83.0 ± 49.9 W, p = 0.020) and vertical jump (TRD 91.6 ± 59.8 W; ISR 147.7 ± 52.0 W; p = 0.036) with squat power approaching significance (TRD 204.9 ± 70.2 W; ISR 282.1 ± 104.2 W; p = 0.053) after post hoc analysis (p < 0.10). The ISR produced greater gains in bench (TRD 9.1 ± 3.7 kg; ISR 15.1 ± 8.3 kg; p = 0.010) and squat (TRD 48.5 ± 17.4 kg; ISR 63.8 ± 12.0 kg; p = 0.002) strength. Both protocols produced significant gains in lean mass with no significant differences between groups (1.6 ± 2.1 kg; p = 0.869). The MHCIIx percentage decreased (-31.0 ± 24.5%; p = 0.001), whereas the MHCIIA percentage increased (28.9 ± 28.5%; p = 0.001) with no significant differences between groups. Results indicate that hypertrophy training with ISR produces greater gains in strength and power, with similar gains in lean mass and MHC alterations as TRD. The ISR may be best used in hypertrophic training for strength and power sports.


Assuntos
Exercício Físico/fisiologia , Força Muscular , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Descanso/fisiologia , Adulto , Desempenho Atlético/fisiologia , Composição Corporal , Teste de Esforço , Humanos , Estudos Longitudinais , Masculino , Cadeias Pesadas de Miosina/metabolismo , Músculo Quadríceps/metabolismo , Adulto Jovem
2.
Artif Intell Med ; 96: 59-67, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31164211

RESUMO

We introduce OntoSIDES, the core of an ontology-based learning management system in Medicine, in which the educational content, the traces of students' activities and the correction of exams are linked and related to items of an official reference program in a unified RDF data model. OntoSIDES is an RDF knowledge base comprised of a lightweight domain ontology that serves as a pivot high-level vocabulary of the query interface with users, and of a dataset made of factual statements relating individual entities to classes and properties of the ontology. Thanks to an automatic mapping-based data materialization and rule-based data saturation, OntoSIDES contains around 8 millions triples to date, and provides an integrated access to useful information for student progress monitoring, using a powerful query language (namely SPARQL) allowing users to express their specific needs of data exploration and analysis. Since we do not expect end-users to master the raw syntax of SPARQL and to express directly complex queries in SPARQL, we have designed a set of parametrized queries that users can instantiate through a user-friendly interface.


Assuntos
Instrução por Computador , Educação Médica/organização & administração , Gestão da Informação/organização & administração , Internet , Bases de Dados Factuais , Humanos , Aprendizagem , Semântica , Interface Usuário-Computador
3.
Psychophysiology ; 56(7): e13363, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30883805

RESUMO

Studies concerning personal attachment have successfully used loved familiar faces to prompt positive affective and physiological reactions. Moreover, the processing of emotional words shows similar physiological patterns to those found with affective pictures. The objective of this study was to assess whether the passive viewing of loved names would produce a pattern of subjective and physiological reactivity similar to that produced by the passive viewing of loved faces. The results showed that, compared to neutral (unknown) and famous names, loved names produced a biphasic pattern of heart rate deceleration-acceleration, heightened skin conductance and zygomaticus muscle activity, inhibition of corrugator muscle activity, and potentiation of the startle reflex response. This pattern of physiological responses was accompanied by subjective reports of higher positive affect and arousal for loved names than for neutral and famous ones. These findings highlight not only the similarity but also the differences between the affective processing of identity recognition by loved faces and names.


Assuntos
Afeto/fisiologia , Nível de Alerta/fisiologia , Emoções/fisiologia , Resposta Galvânica da Pele/fisiologia , Frequência Cardíaca/fisiologia , Nomes , Reconhecimento Psicológico/fisiologia , Adolescente , Adulto , Feminino , Humanos , Adulto Jovem
4.
Int J Psychophysiol ; 100: 1-11, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26724251

RESUMO

To assess the integration of peripheral (heart rate, HR) and central (event-related potential, P300) measures of cognition, the present study varied inter-stimulus presentation time (ISI) and employed comparable data reduction methods for the HR and ERP data. Young adults (n=33) performed an auditory oddball count task in which the ISI was varied (short vs. long, to maximize target detection for both measures) and task condition (single stimulus, short-ISI oddball, long-ISI oddball, to assay stimulus presentation condition between HR and P300). The off-line cardiotachometer method parallels signal averaging and was applied to HR data reduction. The main goal was to characterize target vs. standard processing in each measurement type using appropriate recording approaches with respect to differentiating the two stimuli in each task (target vs. silence, target vs. standard short-ISI, target vs. standard long-ISI). Results demonstrated reliable differences between target/standard stimuli for both the biphasic HR (deceleration/acceleration) signal and for P300 amplitude production, with larger amplitudes for target than standard. The short and long ISIs yielded no reliable initial HR deceleration differences, but the late acceleration was observed for the long-ISI condition only. Correlational analysis between HR and P300 measures indicated that people with smaller HR deceleration had larger P300 amplitude suggesting that the larger target/standard differences for HR deceleration and P300 amplitude, observed at an experimental level, are reversed at an individual level. The contributions of simultaneously recording HR and P300 to characterize cognition and theoretical implications are discussed.


Assuntos
Cognição/fisiologia , Potenciais Evocados P300/fisiologia , Frequência Cardíaca/fisiologia , Estimulação Acústica , Adolescente , Adulto , Análise de Variância , Eletrocardiografia , Eletroencefalografia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Psicoacústica , Fatores de Tempo , Adulto Jovem
5.
J Int Soc Sports Nutr ; 11(1): 6, 2014 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-24568653

RESUMO

BACKGROUND: Extracts of Russian Tarragon (RT) have been reported to produce anti-hyperglycemic effects and influence plasma creatine (Cr) levels while supplementing with creatine monohydrate (CrM). The purpose of this preliminary study was to determine if short-term, low-dose aqueous RT extract ingestion prior to CrM supplementation influences whole body Cr retention, muscle Cr or measures of anaerobic sprint performance. METHODS: In a double-blind, randomized, and crossover manner; 10 recreationally trained males (20 ± 2 yrs; 179 ± 9 cm; 91.3 ± 34 kg) ingested 500 mg of aqueous RT extract (Finzelberg, Andernach, Germany) or 500 mg placebo 30-minutes prior to ingesting 5 g of CrM (Creapure®, AlzChem AG, Germany) twice per day for 5-days then repeated after a 6-week wash-out period. Urine was collected at baseline and during each of the 5-days of supplementation to determine urine Cr content. Whole body Cr retention was estimated from urine samples. Muscle biopsies were obtained for determination of muscle free Cr content. Participants also performed two 30-second Wingate anaerobic capacity tests prior to and following supplementation for determination of peak power (PP), mean power (MP), and total work (TW). Data were analysed by repeated measures MANOVA. RESULTS: Whole body daily Cr retention increased in both groups following supplementation (0.0 ± 0.0; 8.2 ± 1.4, 6.5 ± 2.4, 5.6 ± 3.2, 6.1 ± 2.6, 4.8 ± 3.2 g · d-1; p = 0.001) with no differences observed between groups (p = 0.59). After 3 and 5-days of supplementation, respectively, both supplementation protocols demonstrated a significant increase in muscle free Cr content from baseline (4.8 ± 16.7, 15.5 ± 23.6 mmol · kg-1 DW, p = 0.01) with no significant differences observed between groups (p = 0.34). Absolute change in MP (9 ± 57, 35 ± 57 W; p = 0.031), percent change in MP (2.5 ± 10.5, 6.7 ± 10.4%; p = 0.026), absolute change in TW (275 ± 1,700, 1,031 ± 1,721 J; p = 0.032), and percent change in TW (2.5 ± 10.5, 6.6 ± 10.4%; p = 0.027) increased over time in both groups with no differences observed between groups. CONCLUSIONS: Short-term CrM supplementation (10 g · d-1 for 5-days) significantly increased whole body Cr retention and muscle free Cr content. However, ingesting 500 mg of RT 30-min prior to CrM supplementation did not affect whole body Cr retention, muscle free Cr content, or anaerobic sprint capacity in comparison to ingesting CrM with a placebo.

6.
PLoS One ; 7(7): e41631, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22911829

RESUMO

We have known for decades that social support is associated with positive health outcomes. And yet, the neurophysiological mechanisms underlying this association remain poorly understood. The link between social support and positive health outcomes is likely to depend on the neurophysiological regulatory mechanisms underlying reward and defensive reactions. The present study examines the hypothesis that emotional social support (love) provides safety cues that activate the appetitive reward system and simultaneously inhibit defense reactions. Using the startle probe paradigm, 54 undergraduate students (24 men) viewed black and white photographs of loved (romantic partner, father, mother, and best friend), neutral (unknown), and unpleasant (mutilated) faces. Eye-blink startle, zygomatic major activity, heart rate, and skin conductance responses to the faces, together with subjective ratings of valence, arousal, and dominance, were obtained. Viewing loved faces induced a marked inhibition of the eye-blink startle response accompanied by a pattern of zygomatic, heart rate, skin conductance, and subjective changes indicative of an intense positive emotional response. Effects were similar for men and women, but the startle inhibition and the zygomatic response were larger in female participants. A comparison between the faces of the romantic partner and the parent who shares the partner's gender further suggests that this effect is not attributable to familiarity or arousal. We conclude that this inhibitory capacity may contribute to the health benefits associated with social support.


Assuntos
Mecanismos de Defesa , Promoção da Saúde , Amor , Percepção Visual/fisiologia , Nível de Alerta/fisiologia , Face , Pai , Feminino , Resposta Galvânica da Pele/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Mães , Músculos/fisiologia , Reflexo de Sobressalto/fisiologia , Zigoma/fisiologia
7.
J Int Soc Sports Nutr ; 9(1): 43, 2012 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-22971354

RESUMO

BACKGROUND: Creatine monohydrate (CrM) has been consistently reported to increase muscle creatine content and improve high-intensity exercise capacity. However, a number of different forms of creatine have been purported to be more efficacious than CrM. The purpose of this study was to determine if a buffered creatine monohydrate (KA) that has been purported to promote greater creatine retention and training adaptations with fewer side effects at lower doses is more efficacious than CrM supplementation in resistance-trained individuals. METHODS: In a double-blind manner, 36 resistance-trained participants (20.2 ± 2 years, 181 ± 7 cm, 82.1 ± 12 kg, and 14.7 ± 5% body fat) were randomly assigned to supplement their diet with CrM (Creapure® AlzChem AG, Trostberg, Germany) at normal loading (4 x 5 g/d for 7-days) and maintenance (5 g/d for 21-days) doses; KA (Kre-Alkalyn®, All American Pharmaceutical, Billings, MT, USA) at manufacturer's recommended doses (KA-L, 1.5 g/d for 28-days); or, KA with equivalent loading (4 x 5 g/d for 7-days) and maintenance (5 g/d) doses of CrM (KA-H). Participants were asked to maintain their current training programs and record all workouts. Muscle biopsies from the vastus lateralis, fasting blood samples, body weight, DEXA determined body composition, and Wingate Anaerobic Capacity (WAC) tests were performed at 0, 7, and 28-days while 1RM strength tests were performed at 0 and 28-days. Data were analyzed by a repeated measures multivariate analysis of variance (MANOVA) and are presented as mean ± SD changes from baseline after 7 and 28-days, respectively. RESULTS: Muscle free creatine content obtained in a subgroup of 25 participants increased in all groups over time (1.4 ± 20.7 and 11.9 ± 24.0 mmol/kg DW, p = 0.03) after 7 and 28-days, respectively, with no significant differences among groups (KA-L -7.9 ± 22.3, 4.7 ± 27.0; KA-H 1.0 ± 12.8, 9.1 ± 23.2; CrM 11.3 ± 23.9, 22.3 ± 21.0 mmol/kg DW, p = 0.46). However, while no overall group differences were observed (p = 0.14), pairwise comparison between the KA-L and CrM groups revealed that changes in muscle creatine content tended to be greater in the CrM group (KA-L -1.1 ± 4.3, CrM 11.2 ± 4.3 mmol/kg DW, p = 0.053 [mean ± SEM]). Although some significant time effects were observed, no significant group x time interactions (p > 0.05) were observed in changes in body mass, fat free mass, fat mass, percent body fat, or total body water; bench press and leg press 1RM strength; WAC mean power, peak power, or total work; serum blood lipids, markers of catabolism and bone status, and serum electrolyte status; or, whole blood makers of lymphocytes and red cells. Serum creatinine levels increased in all groups (p < 0.001) with higher doses of creatine promoting greater increases in serum creatinine (p = 0.03) but the increases observed (0.1 - 0.2 mg/dl) were well within normal values for active individuals (i.e., <1.28 ± 0.2 mg/dl). Serum LDL was decreased to a greater degree following ingesting loading doses in the CrM group but returned to baseline during the maintenance phase. No side effects were reported. CONCLUSIONS: Neither manufacturers recommended doses of KA (1.5 g/d) or KA with equivalent loading (20 g/d for 7-days) and maintenance doses (5 g/d for 21-days) of CrM promoted greater changes in muscle creatine content, body composition, strength, or anaerobic capacity than CrM (20 g/d for 7-days, 5 g/d for 21-days). There was no evidence that supplementing the diet with a buffered form of creatine resulted in fewer side effects than CrM. These findings do not support claims that consuming a buffered form of creatine is a more efficacious and/or safer form of creatine to consume than creatine monohydrate.

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