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1.
Artigo em Inglês | MEDLINE | ID: mdl-36834100

RESUMO

In recent years, physical activity assessment has increasingly relied on wearable monitors to provide measures for surveillance, intervention, and epidemiological research. This present systematic review aimed to examine the current research about the utilization of wearable technology in the evaluation in physical activities of preschool- and school-age children. A database search (Web of Science, PubMed and Scopus) for original research articles was performed. A total of twenty-one articles met the inclusion criteria, and the Cochrane risk of bias tool was used. Wearable technology can actually be a very important instrument/tool to detect the movements and monitor the physical activity of children and adolescents. The results revealed that there are a few studies on the influence of these technologies on physical activity in schools, and most of them are descriptive. In line with previous research, the wearable devices can be used as a motivational tool to improve PA behaviors and in the evaluation of PA interventions. However, the different reliability levels of the different devices used in the studies can compromise the analysis and understanding of the results.


Assuntos
Exercício Físico , Dispositivos Eletrônicos Vestíveis , Criança , Pré-Escolar , Adolescente , Humanos , Reprodutibilidade dos Testes , Instituições Acadêmicas , Motivação
2.
Artigo em Inglês | MEDLINE | ID: mdl-34067861

RESUMO

Development of innovative and time-efficient strategies to involve youth in physical activity is pivotal in the actual inactivity pandemic. Moreover, physical activity may improve academic performance, of great interest for educators. This present systematic review aimed to analyze the effects of high-intensity interval training (HIIT) on cognitive performance and psychological outcomes in youth. A database search (Web of Science, PubMed, Scopus, and PsycINFO) for original research articles was performed. A total of eight articles met the inclusion criteria, and the Cochrane risk of bias tool was used. The studies' results were recalculated to determine effect sizes using Cohen's d. Different HIIT interventions reported improvements on cognitive performance at executive function (d = 0.75, +78.56%), linguistic reasoning (d = 0.25, +7.66%), concentration (d = 0.71, +61.10%), selective attention (d = 0.81, +60.73%), non-verbal and verbal abilities (d = 0.88, +47.50%; d = 1.58, +22.61%, respectively), abstract reasoning (d = 0.75, +44.50%), spatial and numerical abilities (d = 37.19, +22.85%; d = 1.20, +8.28%, respectively), and verbal reasoning (d = 1.00, +15.71%) in youth. Regarding psychological outcomes, HIIT showed higher self-concept (d = 0.28, +8.71%) and psychological well-being in boys and girls (d = 0.73, +32.43%, d = 0.39, +11.58%, respectively). To sum up, HIIT interventions between 4-16 weeks, for 8-30 min/session, at ≥85% maximal heart rate, would provide positive effects on cognitive performance and psychological outcomes in youth.


Assuntos
Treinamento Intervalado de Alta Intensidade , Adolescente , Atenção , Cognição , Função Executiva , Exercício Físico , Feminino , Humanos , Masculino
3.
J Strength Cond Res ; 35(12): 3341-3347, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32187149

RESUMO

ABSTRACT: Gil, MH, Neiva, HP, Alves, AR, Sousa, AC, Ferraz, R, Marques, MC, and Marinho, DA. The effect of warm-up running technique on sprint performance. J Strength Cond Res 35(12): 3341-3347, 2021-The purpose of the current study was to analyze the effect of changing the running technique during warm-up on sprint performances, running biomechanics, physiological, and psychophysiological responses. Thirty-one physically active men aged 18-23 years (mean ± SD: 19.35 ± 1.08 years of age; 1.77 ± 0.07 m of height; 71.90 ± 10.37 kg of body mass) volunteered to participate and randomly performed 2 maximal 30-m sprints, 5 minutes after completing a warm-up focused on increased stride length-SL (WUL) or a warm-up focused on increased stride frequency-SF (WUF). The results showed that there were no differences between the 30-m sprint performances and in running biomechanics. However, WUF showed increased performances in the first 15 m of the race (WUF: 2.59 ± 0.11 seconds vs. WUL: 2.63 ± 0.15 seconds; p = 0.03), and WUL resulted in higher performances in the last 15 m (1.94 ± 0.19 seconds vs. 1.88 ± 0.09 seconds; p = 0.05). In the second 30-m time trial, WUF also resulted in faster starting 15 m of the race (2.58 ± 0.12 seconds vs. 2.63 ± 0.16 seconds; p = 0.04). Interestingly, the WUF was the warm-up that revealed more stability in performances and running biomechanics between both trials. These results showed that there were no significant differences between warm-ups comprising exercises focusing in higher SL or higher SF in 30-m sprint biomechanics and performance. Nevertheless, different running strategies were caused by those 2 warm-ups and a more stabilized running pattern, and performance values were found when warm-up focused on higher SF.


Assuntos
Desempenho Atlético , Exercício de Aquecimento , Adolescente , Adulto , Fenômenos Biomecânicos , Estatura , Humanos , Lactente , Masculino , Adulto Jovem
4.
Artigo em Inglês | MEDLINE | ID: mdl-32998211

RESUMO

Fight analysis produces relevant technical-tactical information. However, this knowledge is limited in hybrid full-contact combat sports. Therefore, this study aimed to characterize the results of the fights' outcomes through the winners at the World Ultimate Full Contact (WUFC) Championships between 2008 and 2017. Methods: 170 combats between senior male fighters (master class) from 38 countries were observed; all fight outcome methods, their occurrence times, inherent skills and their development forms were analyzed through frequencies, percentages, crosstabs and chi-square test, considering a Fisher's exact value of p < 0.05. The fight outcome methods were, in decreasing order, as follows: submission; decision and technical knockout (TKO); knockout (KO); and doctor stoppage. Only 19.4% fights completed the regular time 10 min (600 s), and 68.8% fight outcomes occurred in the first 5 min (300 s). Chokes were more used than joint locks, primarily developed in single actions. Head punches and kicks were the skills most responsible for KO, developed more in combinations and counter-attacks, while TKO was always through combination attacks and mostly by ground and pound. Ground fighting is most effective. In stand-up fighting, combination attacks and counter-attack are most effective. It is important to increase the technical-tactical capacities and adjustable decision-making to perform the regular fight time.


Assuntos
Desempenho Atlético , Artes Marciais , Comportamento Competitivo , Traumatismos Craniocerebrais , Humanos , Masculino , Estudos de Tempo e Movimento
5.
Artigo em Inglês | MEDLINE | ID: mdl-32971729

RESUMO

The current study aims to verify the effects of three specific warm-ups on squat and bench press resistance training. Forty resistance-trained males (19-30 years) performed 3 × 6 repetitions with 80% of maximal dynamic strength (designated as training load) after one of the following warm-ups (48 h between): (i) 2 × 6 repetitions with 40% and 80% of the training load (WU), (ii) 6 × 80% of training load (WU80), or (iii) 6 × 40% of the training load (WU40). Mean propulsive velocity (MPV), velocity loss (VL), peak velocity (PV), time to achieve PV, power, work, heart rates, and ratings of perceived exertion were analyzed. In squat exercises, higher MPV were found in WU80 compared with WU40 (2nd set: 0.69 ± 0.09 vs. 0.67 ± 0.06 m.s-1, p = 0.02, ES = 0.80; 3rd set: 0.68 ± 0.09 vs. 0.66 ± 0.07 m.s-1, p = 0.05, ES = 0.51). In bench press exercises, time to PV was lower in WU compared with WU40 (1st set: 574.77 ± 233.46 vs. 694.50 ± 211.71 m.s-1, p < 0.01, ES = 0.69; 2nd set: 533.19 ± 272.22 vs. 662.31 ± 257.51 m.s-1, p = 0.04, ES = 0.43) and total work was higher (4749.90 ± 1312.99 vs. 4631.80 ± 1355.01 j, p = 0.01, ES = 0.54). The results showed that force outputs were mainly optimized by WU80 in squat training and by WU in bench press training. Moreover, warming-up with few repetitions and low loads is not enough to optimize squat and bench press performances.


Assuntos
Treinamento Resistido , Levantamento de Peso , Adulto , Humanos , Masculino , Força Muscular , Músculo Esquelético , Adulto Jovem
6.
J Sports Med Phys Fitness ; 60(4): 501-509, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32037786

RESUMO

BACKGROUND: Warm-up is considered essential to optimize running performance, but little is known about the effect of specific warm-up tasks, specifically in the real competitive context. The current study aimed to verify the acute effects of a warm-up including ballistic exercises in 30m running performance. In addition, a second 30m trial was assessed to better understand the warm-up effects in training/competition. METHODS: Twenty-two men (19.32±1.43 years-old) randomly completed the time-trials on separate days and after a typical warm-up (WU), a WU complemented with ballistic exercises (postactivation potentiation [PAP]) or no warm-up (NWU). Biomechanical, physiological and psychophysiological variables were assessed. RESULTS: The participants were 1.9% faster in the first 30m sprint after WU compared with NWU, mainly increased performance in the first 15m (P=0.03, ES=0.48). WU resulted in greater stride length in the last 15m of the first sprint. PAP did not differ from NWU and WU, despite eight participants performed better after this warm-up. CONCLUSIONS: These results highlight the positive effects of warm-up for sprinting, despite failed to evidence positive effects when ballistic exercises are included. In addition, the influence of warm-up in the running technique was highlighted by the changes in the running kinematics and a need for individualization of warm-up procedures.


Assuntos
Corrida/fisiologia , Exercício de Aquecimento , Adolescente , Adulto , Desempenho Atlético , Fenômenos Biomecânicos , Humanos , Masculino , Adulto Jovem
7.
J Strength Cond Res ; 34(9): 2565-2574, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30946274

RESUMO

Sousa, AC, Neiva, HP, Gil, MH, Izquierdo, M, Rodríguez-Rosell, D, Marques, MC, and Marinho, DA. Concurrent training and detraining: the influence of different aerobic intensities. J Strength Cond Res 34(9): 2565-2574, 2020-The aim of this study was to verify the effects of different aerobic intensities combined with the same resistance training on strength and aerobic performances. Thirty-nine men were randomly assigned to a low-intensity group (LIG), moderate-intensity group (MIG), high-intensity group (HIG), and a control group. The training program consisted of full squat, jumps, sprints, and running at 80% (LIG), 90% (MIG), or 100% (HIG) of the maximal aerobic speed for 16-20 minutes. The training period lasted for 8 weeks, followed by 4 weeks of detraining. Evaluations included 20-m sprints (0-10 m: T10; 0-20 m: T20), shuttle run, countermovement jump (CMJ), and strength (1RMest) in full squat. There were significant improvements from pre-training to post-training in T10 (LIG: 4%; MIG: 5%; HIG: 2%), T20 (3%; 4%; 2%), CMJ (9%; 10%; 7%), 1RMest (13%; 7%; 8%), and oxygen uptake (V[Combining Dot Above]O2max; 10%; 11%; 10%). Comparing the changes between the experimental groups, 1RMest gains were significantly higher in the LIG than HIG (5%) or MIG (6%). Furthermore, there was a tendency for higher gains in LIG and MIG compared with HIG, with "possibly" or "likely" positive effects in T10, T20, and CMJ. Detraining resulted in performance decrements, but minimal losses were found for V[Combining Dot Above]O2max in LIG (-1%). Concurrent training seems to be beneficial for strength and aerobic development regardless of the aerobic training intensity. However, choosing lower intensities can lead to increased strength and is recommended when the cardiorespiratory gains should be maintained for longer.


Assuntos
Treinamento Resistido/métodos , Adolescente , Adulto , Feminino , Humanos , Masculino , Força Muscular/fisiologia , Consumo de Oxigênio/fisiologia , Adulto Jovem
8.
Int J Sports Med ; 40(12): 747-755, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31476783

RESUMO

Concurrent resistance and aerobic training (CT) has been applied to optimize both strength and aerobic performance. However, it should be carefully prescribed, as there are some factors, as the training intensity, which have strong influence on training adaptations. Thus, we conducted a systematic review to analyze the scientific evidence regarding aerobic and resistance exercise intensities during CT and their effect on performance outcomes. The effects of exercise intensity on a subsequent detraining period were also assessed. Nine studies met the inclusion criteria, the risk of bias was assessed, and the percentage of changes and effect sizes were quantified. CT improved running times (10 m, 30 m and 10 km) and strength performance (one-repetition maximum, countermovement jump) regardless of exercise intensity used (4-47%, ES=0.4-2.8). Nevertheless, higher aerobic training intensities (≥ lactate threshold intensity) resulted in higher aerobic gains (5-10%, ES=0.3-0.6), and greater neuromuscular adaptations were found when higher resistance loads (≥ 70% of maximal strength) were used (10-14%, ES=0.4-1.3). Most training-induced gains were reversed after 2-4 weeks of detraining. Although further research is needed, it seems that higher intensities of aerobic or resistance training induce greater aerobic or neuromuscular gains, respectively. Nevertheless, it seems that higher resistance training loads should be combined with lower aerobic training intensities for increased strength gains and minimal losses after detraining.


Assuntos
Força Muscular/fisiologia , Condicionamento Físico Humano/métodos , Resistência Física/fisiologia , Treinamento Resistido/métodos , Adaptação Fisiológica , Humanos
9.
Bernardete, Weber; Bersch, Ferreira  C; Torreglosa, Camila R; Marcadenti, Aline; Lara, Enilda S; Silva, Jaqueline T da; Costa, Rosana P; Santos, Renato H N; Berwanger, Otavio; Bosquetti, Rosa; Pagano, Raira; Mota, Luis G S; Oliveira, Juliana D de; Soares, Rafael M; Galante, Andrea P; Silva, Suzana A da; Zampieri, Fernando G; Kovacs, Cristiane; Amparo, Fernanda C; Moreira, Priscila; Silva, Renata A da; Santos, Karina G dos; Monteiro, Aline S5,; Paiva, Catharina C J; Magnoni, Carlos D; Moreira, Annie S; Peçanha, Daniela O; Missias, Karina C S; Paula, Lais S de; Marotto, Deborah; Souza, Paula; Martins, Patricia R T; Santos, Elisa M dos; Santos, Michelle R; Silva, Luisa P; Torres, Rosileide S; Barbosa, Socorro N A A; Pinho, Priscila M de; Araujo, Suzi H A de; Veríssimo, Adriana O L; Guterres, Aldair S; Cardoso, Andrea F R; Palmeira, Moacyr M; Ataíde, Bruno R B de; Costa, Lilian P S; Marinho, Helyde A; Araújo, Celme B P de; Carvalho, Helen M S; Maquiné, Rebecca O; Caiado, Alessandra C; Matos, Cristina H de; Barretta, Claiza; Specht, Clarice M; Onofrei, Mihaela; Bertacco, Renata T A; Borges, Lucia R; Bertoldi, Eduardo G; Longo, Aline; Ribas, Bruna L P; Dobke, Fernanda; Pretto, Alessandra D B; Bachettini, Nathalia P; Gastaud, Alexandre; Necchi, Rodrigo; Souza, Gabriela C; Zuchinali, Priccila; Fracasso, Bianca M; Bobadra, Sara; Sangali, Tamirys D; Salamoni, Joyce; Garlini, Luíza M; Shirmann, Gabriela S; Los Santos, Mônica L P de; Bortonili, Vera M S; Santos, Cristiano P dos; Bragança, Guilherme C M; Ambrózio, Cíntia L; Lima, Susi B E; Schiavini, Jéssica; Napparo, Alechandra S; Boemo, Jorge L; Nagano, Francisca E Z; Modanese, Paulo V G; Cunha, Natalia M; Frehner, Caroline; Silva, Lannay F da; Formentini, Franciane S; Ramos, Maria E M; Ramos, Salvador S; Lucas, Marilia C S; Machado, Bruna G; Ruschel, Karen B; Beiersdorf, Jâneffer R; Nunes, Cristine E; Rech, Rafael L; Damiani, Mônica; Berbigier, Marina; Poloni, Soraia; Vian, Izabele; Russo, Diana S; Rodrigues, Juliane; Moraes, Maria A P de; Costa, Laura M da; Boklis, Mirena; El Kik, Raquel M; Adorne, Elaine F; Teixeira, Joise M; Trescastro, Eduardo P; Chiesa, Fernanda L; Telles, Cristina T; Pellegrini, Livia A; Reis, Lucas F; Cardoso, Roberta G M; Closs, Vera E; Feres, Noel H; Silva, Nilma F da; Silva, Neyla E; Dutra, Eliane S; Ito, Marina K; Lima, Mariana E P; Carvalho, Ana P P F; Taboada, Maria I S; Machado, Malaine M A; David, Marta M; Júnior, Délcio G S; Dourado, Camila; Fagundes, Vanessa C F O; Uehara, Rose M; Sasso, Sandramara; Vieira, Jaqueline S O; Oliveira, Bianca A S de; Pereira, Juliana L; Rodrigues, Isa G; Pinho, Claudia P S; Sousa, Antonio C S; Almeida, Andreza S; Jesus, Monique T de; Silva, Glauber B da; Alves, Lucicna V S; Nascimento, Viviane O G; Vieira, Sabrina A; Coura, Amanda G L; Dantas, Clenise F; Leda, Neuma M F S; Medeiros, Auriene L; Andrade, Ana C L; Pinheiro, Josilene M F; Lima, Luana R M de; Sabino, L S; Souza, C V S de; Vasconcelos, S M L; Costa, F A; Ferreira, R C; Cardoso, I B; Navarro, L N P; Ferreira, R B; Júnior, A E S; Silva, M B G; Almeida, K M M; Penafort, A M; Queirós, A P O de; Farias, G M N; Carlos, D M O; Cordeiro, C G N C; Vasconcelos, V B; Araújo, E M V M C de; Sahade, V; Ribeiro, C S A; Araujo, G A; Gonçalves, L B; Teixeira, C S; Silva, L M A J; Costa, L B de; Souza, T S; Jesus, S O de; Luna, A B; Rocha, B R S da; Santos, M A; Neto, J A F; Dias, L P P; Cantanhede, R C A; Morais, J M; Duarte, R C L; Barbosa, E C B; Barbosa, J M A; Sousa, R M L de; Santos, A F dos; Teixeira, A F; Moriguchi, E H; Bruscato, N M; Kesties, J; Vivian, L; Carli, W de; Shumacher, M; Izar, M C O; Asoo, M T; Kato, J T; Martins, C M; Machado, V A; Bittencourt, C R O; Freitas, T T de; Sant'Anna, V A R; Lopes, J D; Fischer, S C P M; Pinto, S L; Silva, K C; Gratão, L H A; Holzbach, L C; Backes, L M; Rodrigues, M P; Deucher, K L A L; Cantarelli, M; Bertoni, V M; Rampazzo, D; Bressan, J; Hermsdorff, H H M; Caldas, A P S; Felício, M B; Honório, C R; Silva, A da; Souza, S R; Rodrigues, P A; Meneses, T M X de; Kumbier, M C C; Barreto, A L; Cavalcanti, A B.
Am. heart j ; 215: 187-197, Set. 2019. graf, tab
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1023356

RESUMO

Background Complex percutaneous coronary intervention (PCI) is associated with higher ischemic risk, which can be mitigated by long-term dual antiplatelet therapy (DAPT). However, concomitant high bleeding risk (HBR) may be present, making it unclear whether short- or long-term DAPT should be prioritized. Objectives This study investigated the effects of ischemic (by PCI complexity) and bleeding (by PRECISE-DAPT [PRE dicting bleeding Complications in patients undergoing stent Implantation and Sub sequent Dual Anti Platelet Therapy] score) risks on clinical outcomes and on the impact of DAPT duration after coronary stenting. Methods Complex PCI was defined as ≥3 stents implanted and/or ≥3 lesions treated, bifurcation stenting and/or stent length >60 mm, and/or chronic total occlusion revascularization. Ischemic and bleeding outcomes in high (≥25) or non-high (<25) PRECISE-DAPT strata were evaluated based on randomly allocated duration of DAPT. Results Among 14,963 patients from 8 randomized trials, 3,118 underwent complex PCI and experienced a higher rate of ischemic, but not bleeding, events. Long-term DAPT in non-HBR patients reduced ischemic events in both complex (absolute risk difference: −3.86%; 95% confidence interval: −7.71 to +0.06) and noncomplex PCI strata (absolute risk difference: −1.14%; 95% confidence interval: −2.26 to −0.02), but not among HBR patients, regardless of complex PCI features. The bleeding risk according to the Thrombolysis In Myocardial Infarction scale was increased by long-term DAPT only in HBR patients, regardless of PCI complexity. Conclusions Patients who underwent complex PCI had a higher risk of ischemic events, but benefitted from long-term DAPT only if HBR features were not present. These data suggested that when concordant, bleeding, more than ischemic risk, should inform decision-making on the duration of DAPT. (AU)


Assuntos
Humanos , Doenças Cardiovasculares/prevenção & controle , Avaliação Nutricional , Alimentos, Dieta e Nutrição
10.
J Strength Cond Res ; 33(11): 2981-2990, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31453944

RESUMO

Sousa, AC, Gomes, TM, Sousa, MS, Saraiva, AR, Araujo, GS, Figueiredo, T, and Novaes, JS. Static stretch performed after strength training session induces hypotensive response in trained men. J Strength Cond Res 33(11): 2981-2990, 2019-The purpose of this study was to compare the acute effect of 3 different combinations between passive static stretching exercises (SE) with resistance training (RT) on blood pressure (BP) response in normotensive trained men. Twenty-six volunteer subjects (age: 26.1 ± 5.4 years; body mass: 86.5 ± 10.5 kg; height: 1.78 ± 0.6 cm) participated in this study. After assessing 10 repetition maximum loads for the bench press, lat pulldown, shoulder press, leg press, leg extension, and leg curl, the subjects were randomly assigned on 3 experimental conditions: (a) static SE were performed before the RT session (SE + RT); (b) static SE were performed after the RT session (RT + SE); and (c) static SE were performed between the RT session (RTSE). The BP was measured for 60 minutes after the RT session. The 2-way analysis of variance for repeated measures showed no significant difference (p > 0.05) between the experimental conditions. In within comparisons, only the RT + SE experimental condition did not cause significant increases (p = 0.07) on systolic blood pressure (SBP) when compared the baseline and post-test moments (132.2 ± 10.7 vs. 141.3 ± 18.1 mm Hg). In addition, hypotensive effects were found in SBP only in the RT + SE experimental condition when compared SBP baseline (132.2 ± 10.7 mm Hg) vs. SBP30 minutes (121.7 ± 11.8 mm Hg; p = 0.04), SBP45 minutes (120.6 ± 9.8 mm Hg; p = 0.03), and SBP60 minutes (120.0 ± 7.9 mm Hg; p = 0.00). These findings suggest that performing static SE after the RT session provide an ideal combination for a postexercise hypotensive response from 30 minutes after exercise (and this change was enhanced up to 60 minutes). In conclusion, strength and conditioning professionals can prescribe static SE after RT if the goal is to reduce blood pressure after training.


Assuntos
Pressão Sanguínea , Exercícios de Alongamento Muscular/métodos , Hipotensão Pós-Exercício , Treinamento Resistido , Levantamento de Peso , Adulto , Humanos , Masculino , Adulto Jovem
11.
J Strength Cond Res ; 32(3): 632-642, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28902118

RESUMO

Sousa, AC, Marinho, DA, Gil, MH, Izquierdo, M, Rodríguez-Rosell, D, Neiva, HP, and Marques, MC. Concurrent training followed by detraining: does the resistance training intensity matter? J Strength Cond Res 32(3): 632-642, 2018-The aim of this study was to analyze the training and detraining (DT) effects of concurrent aerobic training and resistance training against 3 different external loads on strength and aerobic variables. Thirty-two men were randomly assigned to 4 groups: low-load (LLG, n = 9), moderate-load (MLG, n = 9), high-load (HLG, n = 8), and control group (CG, n = 6). Resistance training consisted of full squat (FS) with a low load (40-55% 1 repetition maximum [1RM]), a moderate load (55-70% 1RM), or a high load (70-85% 1RM) combined with jump and sprint exercises. Aerobic training was performed at 75% of the maximal aerobic speed for 15-20 minutes. The training period lasted for 8-week, followed by 4-week DT. Pretraining, post-training, and post-DT evaluations included 20-m running sprints (0-10 m: T10; 0-20 m: T20), shuttle run test, countermovement vertical jump (CMJ) test, and loading test (1RM) in FS. All the experimental groups showed improvements (p ≤ 0.05) in all the parameters assessed, except the LLG for T10 and the HLG for T20. The LLG, MLG, and HLG showed great changes in 1RM and V[Combining Dot Above]O2max compared with the CG (p ≤ 0.05), whereas the HLG and MLG showed a greater percentage change than the CG in T10 (p < 0.001) and CMJ (p ≤ 0.05). The 4-week DT period resulted in detrimental effects in all variables analyzed for all 3 experimental groups. In conclusion, our results suggest that strength training programs with low, moderate, or high external loads combined with low-intensity aerobic training could be effective for producing significant gains in strength and aerobic capacities. Moreover, the higher loads used increased gains in explosive efforts.


Assuntos
Tolerância ao Exercício/fisiologia , Treinamento Resistido/métodos , Corrida/fisiologia , Adulto , Eletrocardiografia , Teste de Esforço , Humanos , Masculino , Força Muscular/fisiologia , Consumo de Oxigênio , Adulto Jovem
12.
Sci Rep ; 4: 4039, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24509508

RESUMO

We report a new type of magnetic nanofluids, which is based on a hybrid composite of nanodiamond and nickel (ND-Ni) nanoparticles. We prepared the nanoparticles by an in-situ method involving the dispersion of caboxylated nanodiamond (c-ND) nanoparticles in ethylene glycol (EG) followed by mixing of nickel chloride and, at the reaction temperature of 140°C, the use of sodium borohydrate as the reducing agent to form the ND-Ni nanoparticles. We performed their detailed surface and magnetic characterization by X-ray diffraction, micro-Raman, high-resolution transmission electron microscopy, and vibrating sample magnetometer. We prepared stable magnetic nanofluids by dispersing ND-Ni nanoparticles in a mixture of water and EG; we conducted measurements to determine the thermal conductivity and viscosity of the nanofluid with different nanoparticles loadings. The nanofluid for a 3.03% wt. of ND-Ni nanoparticles dispersed in water and EG exhibits a maximum thermal conductivity enhancement of 21% and 13%, respectively. For the same particle loading of 3.03% wt., the viscosity enhancement is 2-fold and 1.5-fold for water and EG nanofluids. This particular magnetic nanofluid, beyond its obvious usage in heat transfer equipment, may find potential applications in such diverse fields as optics and magnetic resonance imaging.

13.
Ultrason Sonochem ; 20(3): 820-5, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23187065

RESUMO

Biodiesel is considered an alternative energy because it is produced from fats and vegetable oils by means of transesterification. Furthermore, it consists of fatty acid alkyl esters (FAAS) which have a great influence on biodiesel fuel properties and in the storage lifetime of biodiesel itself. The biodiesel storage stability is directly related to the oxidative stability parameter (Induction Time - IT) which is determined by means of the Rancimat® method. This method uses condutimetric monitoring and induces the degradation of FAAS by heating the sample at a constant temperature. The European Committee for Standardization established a standard (EN 14214) to determine the oxidative stability of biodiesel, which requires it to reach a minimum induction period of 6h as tested by Rancimat® method at 110°C. In this research, we aimed at developing a fast and simple alternative method to determine the induction time (IT) based on the FAAS ultrasonic-accelerated oxidation. The sonodegradation of biodiesel samples was induced by means of an ultrasonic homogenizer fitted with an immersible horn at 480Watts of power and 20 duty cycles. The UV-Vis spectrometry was used to monitor the FAAS sonodegradation by measuring the absorbance at 270nm every 2. Biodiesel samples from different feedstock were studied in this work. In all cases, IT was established as the inflection point of the absorbance versus time curve. The induction time values of all biodiesel samples determined using the proposed method was in accordance with those measured through the Rancimat® reference method by showing a R(2)=0.998.


Assuntos
Biocombustíveis/análise , Ácidos Graxos não Esterificados/química , Ondas de Choque de Alta Energia , Óleos de Plantas/química , Sonicação , Biocombustíveis/efeitos da radiação , Biocombustíveis/normas , Esterificação , Ácidos Graxos não Esterificados/efeitos da radiação , Ácidos Graxos não Esterificados/normas , Oxirredução , Óleos de Plantas/efeitos da radiação , Óleos de Plantas/normas
14.
Arq. bras. cardiol ; 95(3): 313-320, set. 2010. tab
Artigo em Português | LILACS | ID: lil-560556

RESUMO

FUNDAMENTO: De um ponto de vista mecanístico, a apneia obstrutiva do sono (SAOS) pode causar distúrbios extras à homeostase cardiovascular na presença de síndrome coronariana aguda (SCA). OBJETIVO: Investigar se um diagnóstico clínico padronizado de SAOS, em pacientes com SCA, prediz o risco de eventos cardiovasculares durante hospitalização. MÉTODOS: Em um estudo de coorte prospectivo, um grupo de 200 pacientes com diagnóstico de SCA estabelecido entre Setembro de 2005 e Novembro de 2007, foram estratificados pelo Questionário de Berlim (QB) para o risco de SAOS (alto ou baixo risco). Foi testado se o subgrupo de alto risco para SAOS apresenta maior tendência à eventos cardiovasculares. O endpoint primário avaliado foi um desfecho composto de morte cardiovascular, eventos cardíacos isquêmicos recorrentes, edema pulmonar agudo e acidente vascular cerebral durante a hospitalização. RESULTADOS: Noventa e quatro (47 por cento) dos pacientes identificados pelo QB apresentavam suspeita de SAOS. Alto risco para SAOS estava associado com uma mortalidade mais elevada, embora sem diferença estatística (4,25 por cento vs 0,94 por cento; p=0,189), mas com uma estatisticamente significante maior incidência de desfecho composto de eventos cardiovasculares (18,08 por cento vs 6,6 por cento; p=0,016). No modelo de regressão logística, os preditores multivariados de desfecho composto de eventos cardiovasculares foram idade (OR = 1,048; IC95 por cento: 1,008 a 1,090; p=0,019), fração de ejeção do VE (OR = 0,954; IC95 por cento: 0,920 a 0,989; p=0,010), e risco mais elevado de SAOS (OR = 3,657; IC95 por cento: 1,216 a 10,996; p=0,021). CONCLUSÃO: O uso de um questionário simples e validado (QB) para identificar pacientes com risco mais elevado de SAOS pode ajudar a prever o desfecho cardiovascular durante a hospitalização. Além disso, nossos dados sugerem que SAOS é muito comum em pacientes com SCA.


BACKGROUND: From a mechanistic standpoint, obstructive sleep apnea (OSA) may further disturb cardiovascular homeostasis in the setting of acute coronary syndrome (ACS). OBJECTIVE: We sought to investigate if a standardized clinical diagnosis of OSA, in acute coronary syndrome patients, predicts the risk of cardiovascular events during hospitalization. METHODS: In a prospective cohort study, a group of 200 patients diagnosed with ACS between September 2005 and November 2007 were stratified by the Berlin Questionnaire (BQ) regarding the risk for OSA (high or low risk). We tested if the subgroup of high risk for OSA was prone to a higher frequency of cardiovascular events. The primary endpoint evaluated was a composite outcome of cardiovascular death, recurrent cardiac ischemic events, acute pulmonary edema and stroke during hospitalization. RESULTS: Ninety four (47 percent) patients assessed by the BQ were likely to have OSA. High risk for OSA was associated with a non-significant higher mortality (4.25 percent vs 0.94 percent; p=0.189), but a significant higher incidence of composite cardiovascular events (18.08 percent vs 6.6 percent; p=0.016). In the logistic regression model, multivariate predictors of composite cardiovascular events were age (OR= 1.048; 95 percent CI 1.008 to 1.090; p=0.019), left ventricular ejection fraction (OR= 0.954; 95 percent CI 0.920 to 0.989; p=0.010), and higher risk for OSA (OR= 3.657; 95 percent CI 1.216 to 10.996; p=0.021). CONCLUSION: The use of a simple and validated questionnaire (BQ) to identify patients with higher risk for OSA may help in the prediction of cardiovascular outcome during hospitalization. Moreover, our data suggests that OSA is very common in patients with ACS.


FUNDAMENTO: Desde un punto de vista mecanístico, la apnea obstructiva del sueño (SAOS) puede ocasionar disturbios extras a la homeostasis cardiovascular en la presencia del síndrome coronario aguda (SCA) OBJETIVO: Investigar si un diagnóstico clínico estandarizado de SAOS, en pacientes con SCA, predice el riesgo de eventos cardiovasculares durante la hospitalización. MÉTODOS: En un estudio de cohorte prospectivo, un grupo de 200 pacientes con diagnóstico de SCA elecido entre Septiembre de 2005 y Noviembre de 2007, fueron estratificados por el Cuestionario de Berlín (CB) para el riesgo de SAOS (alto o bajo riesgo). Se probó si el subgrupo de alto riesgo para SAOS presenta mayor tendencia a eventos cardiovasculares. El endpoint primario evaluado fue un desenlace conformado por muerte cardiovascular, eventos cardíacos isquémicos recurrentes, edema pulmonar agudo y accidente vascular cerebral durante la hospitalización. RESULTADOS: Noventa y cuatro (47 por ciento) de los pacientes identificados por el CB presentaban sospecha de SAOS. Alto riesgo para SAOS estaba asociado con una mortalidad más elevada, aunque sin diferencia estadística (4,25 por ciento vs 0,94 por ciento; p=0,189), pero con una estadísticamente significativa mayor incidencia de desenlace conformada por eventos cardiovasculares (18,08 por ciento vs 6,6 por ciento; p=0,016). En el modelo de regresión logística, los predictores multivariados de desenlace conformado por eventos cardiovasculares fueron edad (OR= 1,048; IC95 por ciento: 1,008 a 1,090; p=0,019), fracción de eyección del VI (OR= 0,954; IC95 por ciento: 0,920 a 0,989; p=0,010), y riesgo más elevado de SAOS (OR= 3,657; IC95 por ciento: 1,216 a 10,996; p=0,021). CONCLUSIÓN: El uso de un cuestionario sencillo y validado (CB) para identificar a pacientes con riesgo más elevado de SAOS puede ayudar a prever el desenlace cardiovascular durante la hospitalización. Además de ello, nuestros datos sugieren que SAOS es mucho común en pacientes con SCA.


Assuntos
Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome Coronariana Aguda/etiologia , Hospitalização , Inquéritos e Questionários , Apneia Obstrutiva do Sono/complicações , Síndrome Coronariana Aguda/epidemiologia , Brasil/epidemiologia , Métodos Epidemiológicos , Hospitalização/estatística & dados numéricos , Fatores de Risco , Apneia Obstrutiva do Sono/diagnóstico
15.
Arq Bras Cardiol ; 95(3): 313-20, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20676583

RESUMO

BACKGROUND: From a mechanistic standpoint, obstructive sleep apnea (OSA) may further disturb cardiovascular homeostasis in the setting of acute coronary syndrome (ACS). OBJECTIVE: We sought to investigate if a standardized clinical diagnosis of OSA, in acute coronary syndrome patients, predicts the risk of cardiovascular events during hospitalization. METHODS: In a prospective cohort study, a group of 200 patients diagnosed with ACS between September 2005 and November 2007 were stratified by the Berlin Questionnaire (BQ) regarding the risk for OSA (high or low risk). We tested if the subgroup of high risk for OSA was prone to a higher frequency of cardiovascular events. The primary endpoint evaluated was a composite outcome of cardiovascular death, recurrent cardiac ischemic events, acute pulmonary edema and stroke during hospitalization. RESULTS: Ninety four (47%) patients assessed by the BQ were likely to have OSA. High risk for OSA was associated with a non-significant higher mortality (4.25% vs 0.94%; p=0.189), but a significant higher incidence of composite cardiovascular events (18.08% vs 6.6%; p=0.016). In the logistic regression model, multivariate predictors of composite cardiovascular events were age (OR= 1.048; 95% CI 1.008 to 1.090; p=0.019), left ventricular ejection fraction (OR= 0.954; 95% CI 0.920 to 0.989; p=0.010), and higher risk for OSA (OR= 3.657; 95% CI 1.216 to 10.996; p=0.021). CONCLUSION: The use of a simple and validated questionnaire (BQ) to identify patients with higher risk for OSA may help in the prediction of cardiovascular outcome during hospitalization. Moreover, our data suggests that OSA is very common in patients with ACS.


Assuntos
Síndrome Coronariana Aguda/etiologia , Hospitalização , Apneia Obstrutiva do Sono/complicações , Inquéritos e Questionários , Síndrome Coronariana Aguda/epidemiologia , Brasil/epidemiologia , Métodos Epidemiológicos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Apneia Obstrutiva do Sono/diagnóstico
16.
Cardiovasc Ultrasound ; 7: 24, 2009 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-19480653

RESUMO

BACKGROUND: Coronary artery disease (CAD) is the leading cause of death in diabetic patients. Although exercise echocardiography (EE) is established as a useful method for diagnosis and stratification of risk for CAD in the general population, there are few studies on its value as a prognostic tool in diabetic patients. The purpose of this investigation was to evaluate the value of EE in predicting cardiac events in diabetics. METHODS: 193 diabetic patients, 97 males, 59.8 +/- 9.3 yrs (mean +/- SD) were submitted to EE between 2001 and 2006 and followed from 7 to 65 months with median of 29 months by phone calls and personal interviews with patients and their primary physician, and reviewing medical records and death certificates. The end points were cardiac events, defined as non-fatal myocardial infarction, late myocardial revascularization and cardiac death. Sudden death without another explanation was considered cardiac death. Survival free of end points was estimated by the Kaplan-Meier method. RESULTS: Twenty-six cardiac events were registered in 24 individuals during the follow-up. The rates of cardiac events were 20.6 and 7% in patients with positive and negative EE, respectively (p < 0.001). Predictors of cardiac events included sedentary lifestyle, with RR of 2.57 95%CI [1.09 to 6.02] (P = 0.03) and positive EE, with RR 3.63, 95%CI [1.44 to 9.16] (P = 0.01). Patients with positive EE presented higher rates of cardiac events at 12 months (6.8% vs. 2.2%), p = 0.004. CONCLUSION: EE is a useful method to predict cardiac events in diabetic patients with suspected or known CAD.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/epidemiologia , Ecocardiografia/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Comorbidade , Feminino , Humanos , Incidência , Masculino , Prognóstico , Reprodutibilidade dos Testes , Medição de Risco/métodos , Fatores de Risco , Sensibilidade e Especificidade
17.
Cardiovasc Ultrasound ; 5: 38, 2007 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-17980022

RESUMO

BACKGROUND: Exercise echocardiography (EE) is an established method to diagnose coronary artery disease (CAD). Chronotropic incompetence (CI) during the EE may be a marker of myocardial ischemia. The purpose of this investigation was to evaluate the additive value of CI during EE in CAD diagnosis. METHODS: Between 2000 and 2006, 4042 patients (1900 men with a mean age of 56 +/- 11 years) were evaluated by EE. Based on the heart rate (HR) reached during the exercise test, the subjects were divided into two groups: G1 group - 490 patients who failed to achieve 85% of the maximal age-predicted HR, and G2 group - 3552 patients who were able to achieve 85% of the maximal age-predicted HR. Clinical characteristics, left ventricular wall motion abnormalities - wall motion score index (WMSI) - and coronary angiography (CA) were the parameters compared between the two groups. RESULTS: The left ventricular wall motion abnormalities were more frequent in G1 group than in G2 group (54% versus 26%; P < 0.00001). WMSI was higher in G1 group than in G2 group, both at rest (1.06 +/- 0.17 versus 1.02 +/- 0.09; P < 0.0001) and after exercise (1.12 +/- 0.23 versus 1.04 +/- 0.21; P < 0.0001). In G1 group, 82% of the patients with positive EE for myocardial ischemia presented obstructive coronary, compared to 71% (P = 0.03) in G2 group. CONCLUSION: CI is associated with a higher frequency of myocardial ischemia during EE, reinforcing the concept that CI is a marker of the severity of myocardial ischemia.


Assuntos
Arritmias Cardíacas/diagnóstico por imagem , Arritmias Cardíacas/epidemiologia , Ecocardiografia/estatística & dados numéricos , Teste de Esforço/estatística & dados numéricos , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/epidemiologia , Medição de Risco/métodos , Brasil/epidemiologia , Comorbidade , Teste de Esforço/métodos , Feminino , Frequência Cardíaca , Humanos , Incidência , Masculino , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade
18.
Anal Chim Acta ; 588(2): 231-6, 2007 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-17386815

RESUMO

This paper proposes a method for determination of chemical oxygen demand (COD) in domestic wastewater. The proposed method is based on near-infrared reflectance (NIRR) measurements of seston collected from wastewater samples by filtration. The analysis does not require any special reagent, catalyst or solvent. Inherent baseline and noise features present in NIRR spectra are removed by a Savitzky-Golay derivative procedure followed by wavelet denoising. The resulting wavelet approximation coefficients are used for partial-least-squares modelling and subsequent prediction of COD values in new samples. The model is calibrated by using COD values obtained according to the American Public Health Association (APHA) reference method. The proposed method is applied to effluent samples from the anaerobic ponds of the Mangabeira municipal wastewater treatment plant in the city of João Pessoa (Paraíba, Brazil). By comparing the NIRR prediction results with the APHA reference values, a root-mean-square error of prediction (RMSEP) of 19 mg O2 L(-1) and a correlation of 0.97 were obtained. Such results are deemed adequate in view of the joint estimate of the standard error of the reference method, which was calculated as 21 mg O2 L(-1).

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