RESUMO
To determine the most effective periodization model for strength and hypertrophy is an important step for strength and conditioning professionals. The aim of this study was to compare the effects of linear (LP) and daily undulating periodized (DUP) resistance training on body composition and maximal strength levels. Forty men aged 21.5 +/- 8.3 and with a minimum 1-year strength training experience were assigned to an LP (n = 20) or DUP group (n = 20). Subjects were tested for maximal strength in bench press, leg press 45 degrees, and arm curl (1 repetition maximum [RM]) at baseline (T1), after 8 weeks (T2), and after 12 weeks of training (T3). Increases of 18.2 and 25.08% in bench press 1 RM were observed for LP and DUP groups in T3 compared with T1, respectively (p < or = 0.05). In leg press 45 degrees , LP group exhibited an increase of 24.71% and DUP of 40.61% at T3 compared with T1. Additionally, DUP showed an increase of 12.23% at T2 compared with T1 and 25.48% at T3 compared with T2. For the arm curl exercise, LP group increased 14.15% and DUP 23.53% at T3 when compared with T1. An increase of 20% was also found at T2 when compared with T1, for DUP. Although the DUP group increased strength the most in all exercises, no statistical differences were found between groups. In conclusion, undulating periodized strength training induced higher increases in maximal strength than the linear model in strength-trained men. For maximizing strength increases, daily intensity and volume variations were more effective than weekly variations.
Assuntos
Composição Corporal/fisiologia , Força Muscular/fisiologia , Treinamento Resistido/métodos , Adaptação Fisiológica , Adolescente , Adulto , Análise de Variância , Braço/fisiologia , Síndrome de Adaptação Geral/fisiopatologia , Humanos , Perna (Membro)/fisiologia , Modelos Lineares , Masculino , Dinâmica não Linear , Periodicidade , Dobras Cutâneas , Estatísticas não Paramétricas , Fatores de Tempo , Adulto JovemRESUMO
Nosso objetivo foi estudar a relação entre o nível de estresse avaliado comportamentalmente, e a sensibilidade da resposta cronotrópica à norepinefrina (NE) de ratas submetidas ao estresse por natação. Ratas em estro ou proestro foram submetidas a uma sessão de 50 min. de natação. Foram avaliados o tempo de tentativa de fuga e o tempo de imobilidade durante a natação. Imediatamente após o estresse, ratas estressadas e controles foram sacrificadas e o átrio direito foi isolado para obtenção de curvas concentração-efeito à NE. No proestro, o tempo de tentativa de fuga foi maior do que no estro (p<0,05). O tempo de imobilidade, por outro lado, foi menor no proestro do que no estro (p<0.05)...
Assuntos
Animais , Ratos , Comportamento Animal , Estro , Natação/fisiologia , Norepinefrina , Proestro , Síndrome de Adaptação Geral/fisiopatologia , Síndrome de Adaptação Geral/metabolismo , Coleta de Dados , Estudo de AvaliaçãoRESUMO
The object of this work was to establish whether induced stress leads to morphological changes in the sublingual and submaxillary glands of rats. General adaptation syndrome (S.G.A.) was induced in 25 young adult male Wistar rats through cold and immobilization. The animals were killed 48 hrs. and 10 days after stressor (E.A.) application. To verify stress condition, the adrenales were weighed and plasmatic corticosterone were carried out. The sublingual and submaxillary glands were dissected, fixed in buffered formol and stained with H.E. The results histology indicate that the submaxillary is more sensitive to cold than the sublingual, while the reverse holds true form immobilization.