15 research outputs found
Effect of internal focus of attention with touching cue on the agonist muscle activity during exercise
This study aimed to investigate the effect of internal focus of attention with touching cue on agonist muscular activity during the arm curl exercise. Ten healthy males (age, 20-35 years) performed five repetitions of arm curl under three different focus instructions: external focus condition (EXT), where participants were instructed to concentrate on lifting the bar; internal focus condition (INT), where participants were instructed to concentrate on contractions of biceps brachii; and, internal focus and touch condition (INT+T): participants' biceps brachii was lightly touched by the investigator and they were instructed to concentrate on muscle contractions at the touched point. Although the average muscular activities in INT and INT+T were significantly higher than that of EXT (p < .01), no significant difference in muscle activity between INT and INT+T was observed. Further, magnitudes of these effects were small (d < 0.25). These results suggest that internal focus caused by individual's consciousness, as well as a focus attention by touching the agonist area increased the agonist muscle activity during exercise. However, the increase in agonist muscle activity due to focus attention is limited.Research supported by KAKENHI (Grant-in-Aid for Scientific Research C, Grant Number JP18K06455)
Asymmetry of Force Fluctuation During Low Intensity Isometric Contraction In Leg Muscle
Int J Exerc Sci 3(2) : 68-77, 2010. The purpose of this study was to investigate the asymmetry of force fluctuation in the leg muscles during isometric knee extension and flexion. Twenty healthy males (21±2 years) performed the maximal voluntary isometric contraction (MVC) in knee extensor and flexor. On the basis of MVC measurement, the subjects performed sustained isometric knee extension and flexion for 15s at levels corresponding to 10%, 20% and 30% MVC. The main findings of this study were: (1) a greater force fluctuation was found in the stronger MVC limb than in the weaker MVC limb at 30% MVC; (2) no difference was found in the force fluctuation between the stronger and weaker MVC limbs at 10% and 20% MVC; and (3) significant positive correlations were found between the target force values and the force fluctuation at each contraction intensity. These results suggest that: (1) asymmetry of force fluctuation increases with load, (2) asymmetry of the force fluctuation is observed at more than 30% MVC intensity; and (3) if the contraction intensity is same relatively loads (% MVC), force fluctuation is increase with absolute load (target force value). Force fluctuation influence the functional ability of an individual in controlling finger or limb movements in daily life. Further, asymmetry of force fluctuation might influence for more than 30% MVC of daily activities
Gait Improvement by Alerted Push-Off via Heating of Insole Tip
This study investigated the change in the joint angles of the lower limb during gait by heating the tip of the insole to make a conscious push-off with the warm part. Fifteen healthy males performed treadmill walking under three different conditions: CONTROL walked as usual, INST was instructed to extend the stride with a push-off from the ball of foot to the toe, and HEAT was asked to walk while attempting to push off the warm area, which was attached to the disposable warmer to the area from the ball of foot to the toe of the insole. A 3D-motion capture system with infrared cameras was used to analyze the gait. The hip joint angle increased significantly under the INST and HEAT. Although the ankle dorsi-flexion at heel strike did not differ significantly for these conditions, ankle plantar-flexion significantly increased at toe-off under the INST and HEAT. Especially, effect size (d) in increased plantar-flexion was large in HEAT (=1.50), whereas it was moderate in INST (=0.68). These results suggest that a heated stimulus during gait enhanced the consciousness of push-off and increased leg swing and ankle plantar-flexion during the terminal stance phase, which may increase the stride length
dS4 universe emergent from Kerr-AdS5 spacetime: bubble nucleation catalyzed by a black hole
Abstract The emergence of a four-dimensional de Sitter (dS4) universe on an expanding bubble in the five-dimensional anti-de Sitter (AdS5) background has been suggested as a possible cosmological scenario. It is motivated by the difficulties in the realization of a stable de Sitter vacua in string theory. The bubble can be nucleated in a meta-stable pure AdS5 spacetime, but it is known that a pure AdS spacetime is non-perturbatively unstable. It means that the pure AdS5 background is an idealized situation, and in realistic situations, non-linear perturbations in AdS may lead to the formation of black holes due to the gravitational turbulent instability. To investigate how the proposed scenario works in a more realistic situation, we here study the nucleation process of a vacuum bubble in the Kerr-AdS5 spacetime. Especially we investigate conditions sufficient to ensure the nucleation of a vacuum bubble with a rotating black hole and how the black hole affects the transition rate. We find that even in the Kerr-AdS5 spacetime, a quasi-dS4 expansion can be realized on the nucleated vacuum bubble without contradicting the de Sitter swampland conjectures
Original MEEPQ-morning items and percentage of informants selecting each option.
<p>If you engaged in physical activity in the morning (6–9 AM), what kind of advantages or disadvantages would you experience? For each question, select the answer choice that best describes you.</p
Relationships between the MEEPQ scores and objectively measured activity levels (weekly mean levels).
<p>Relationships between the MEEPQ scores and objectively measured activity levels (weekly mean levels).</p