MUSCLE ACTIVITY IS INCREASED BY LOOKING AT THE TARGET MUSCLES AND FOCUSING ON MUSCLE SQUEEZING. [2176]

Author(s): FUJIWARA, S., NAKAZATO, K., OKADA, T., Institution: NIPPON SPORT SCIENCE UNIVERSITY, Country: JAPAN

INTRODUCTION:
Two types of attentional focuses have been identified: internal and external. It is known that internal focus increases muscle activity by conscious of muscle(1). Thus, internal focus is said to be a mind muscle connection in the bodybuilding and it is useful if muscle development is the purpose. External focus(EF) enhances motor performance by conscious of object(2). However, there is no study on internal focus using visual sense. In the case of conventional internal focus(CIF), subjects were instructed to look forward and focus on internal focus. Therefore, the purpose of this research is to investigate whether internal focus using visual sense can enhance muscle activity.
METHODS:
Nine resistance-untrained men were familiarized with the procedure and one-repetition maximum (1RM) test during session 1. In session 2, subjects performed one hand preacher curl machine three repetitions at 30% 1-repetition max (1RM) while surface electromyographic(sEMG) activity was recorded from the long head of biceps brachii muscle (BB). There was a two minute rest period in between the sets. The order of instructions was randomized between subjects. The subjects was instructed to look forward and focus on lifting the hand bar (EF). In the case of CIF, subjects were instructed to look ahead and focus on muscle squeezing.
Furthermore, subjects were instructed to look at muscles and focus on muscle squeezing(LIF). Mean normalized root mean square EMG activity was calculated during 3 repetition in each condition. Analyses were done with paired tests with Bonferroni’s correction.
RESULTS:
LIF(55.9±9.8%MVC) showed a significant increase in EMG activity than EF(29.8±3.98%MVC) (p<0.05).
The rate of change between LIF and EF was 88% (p<0.05). There was no statistically significant difference between the EF(29.8±3.98%MVC) and CIF(37.8±4.9%MVC)(p>0.05).The rate of change between EF and CIF was 27%(p>0.05).EMG activity was not different between LIF(55.9±9.8%MVC) and CIF(37.8±4.9%MVC)(p>0.05).The rate of change between LIF and CIF was 48%.
CONCLUSION:
In this study, it was found that internal focus is more effective by using visual. Especially for resistance training beginners, it is thought that consciousness becomes easy by looking at the target muscles. Therefore, it suggested to enhance muscle activity and promote muscle development.
1)schoenfeld&contreras, strength and conditioning journal, 2016.
2)wulf,G, sport and exercise psychology, 2013.