YoYo Squat Inertial Technology

PRINCÍPIOS DO YOYO (RESISTÊNCIA ISOINERCIAL)

A tecnologia YoYo™ desenvolveu um novo sistema e uma nova forma de treinamento resistido com o uso de Flywheels – na qual substitui as tradicionais anilhas e outros equipamentos baseados na resistência da gravidade. A resistência do YoYo™ provém de um rotor em movimento, muito similar ao ioiô usado pelas crianças, com o enrolamento e desenrolamento da cinta ao redor de seu eixo acoplado a uma Flywheel fixa.
Uma ação muscular concêntrica (+) inicia o movimento inercial do Flywheels, enquanto que uma ação muscular excêntrica (-) freia o mesmo movimento inercial. Este é o Princípio do YoYo™.

As aplicações do Princípio do YoYo™ são virtualmente ilimitadas. Compacto e leve, este sistema de exercícios é apropriado para qualquer área de atividade física: treino doméstico, paciente em reabilitação, atletas de elite, e até mesmos astronautas. A questão de Resistência Variável oferece ilimitadas formas de treinamento a qualquer usuário, com capacidade infinita de produzir força ou potência. O usuário poderá requerer movimentos curtos e explosivos usando somente um Flywheel, ou fazer treinamentos mais pesados acrescentando mais Flywheels. Usuários avançados podem aproveitar os benefícios do Treinamento em “sobrecarga excêntrica”.

Uma das principais diferenças com respeito aos exercícios convencionais feitos com estações de peso, barras, pesos livres ou dumbbells é que, enquanto com peso a resistência é constante e igual à carga pré-estabelecida (exercícios isotônicos), nos equipamentos YoYo™ a resistência é variável e – a cada repetição – proporcional à força desenvolvida: quanto maior a força, maior será a aceleração na qual o Flywheel retornará (exercícios isoinercial). O exercício termina quando a máxima força exercida diminui, devido à fadiga. Isso implica dizer também que todas as repetições, exceto a última, são, por definição, sub-máximas.

Inversamente, num equipamento YoYo™, cada repetição é executada na máxima força na qual o atleta pode atingir, mesmo que ela diminua com a fadiga. Como conseqüência, a ‘DOSE’ de treinamento (trabalho) para um certo número de repetições, é maior que com peso convencional.

Comparado com exercícios isotônicos, um exercício isoinercial de forças variáveis recria as condições na qual o sistema muscular é normalmente exigido no dia a dia. No esporte, por exemplo, a grande maioria dos movimentos envolve a aceleração e desaceleração de um corpo inercial (por exemplo uma bola ou parte do corpo). O equipamento YoYo™ simula o mesmo princípio de trabalho, transformando a aceleração de uma massa inercial em rotação (o Flywheel), em um movimento mono ou pluri-articular.

PESQUISA E APLICAÇÕES PRÁTICAS

A figura ao lado ilustra um estudo comparativo de 5 semanas, consistindo em 14 sessões de treinamento unilateral dos extensores de joelho numa máquina extensora. O estudo envolveu a participação de 16 indivíduos, metade deles treinados num equipamento convencional e a outra metade numa equipamento YoYo™.

A força máxima e o volume muscular (por RMN) foram comparados antes e após o treinamento. Embora tenha sido observado um incremento no volume muscular em ambos os equipamentos (aprox. 3% no equipamento com peso e 6% no YoYo™), o incremento de força máxima foi significante somente no grupo do YoYo™.

Vários estudos patrocinados pela European Space Agency (ESA) tem sido realizados com objetivo de verificar a efetividade do YoYo™ contra a atrofia muscular. Em um destes estudos, os sujeitos em experimento foram acamados por 90 dias, para induzir a atrofia muscular similar ao que é observado depois de um prolongado tempo no espaço.

Além disso, metade dos sujeitos foram submetidos a um regime de treinamento consistindo em 2 e 3 sessões semanais alternadas, de 4 x 7 repetições em um equipamento 'leg press' do tipo YoYo™.

Conforme gráfico ao lado, embora a duração total dos exercícios em 90 dias tenha sido somente de 30 a 40 min, isso foi suficiente para combater a diminuição do volume da massa muscular, assim como a força explosiva dos movimentos isométricos, concêntrico e excêntricos.

INFORMAÇÕES sobre TREINAMENTO

Vantagens da tecnologia YoYo™ comparada com peso livre ou equipamentos e estação de trabalho:

• Sobrecarga excêntrica
• Toda e qualquer repetição será na força máxima
• Ergonômico e independente da técnica do usuário
• Independente da força gravitacional (movimentação livre)
• Elevada ativação do Glúteo Máximo
• Praticidade para treinamento em grupos heterogêneos
• Econômico e de fácil transporte

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