Immediate effect of neuromuscular electrical stimulation on the abductor hallucis muscle: A randomized controlled trial.

Hallux valgus (HV) is a foot deformity with deviation of the greater toe and the first metatarsal. There is little evidence on training the abductor hallucis muscle (AbdH) to treat HV because of the difficulty in implementing the necessary interventions. Although neuromuscular electrical stimulation (NMES) has been used to induce voluntary exercise, there is currently no study on NMES for AbdH. We aimed to verify the immediate effect of NMES on the AbdH muscle function. For the NMES group (n = 15), electrical stimulation was applied for 20 min. In the sham group (n = 15), the stimulating device was set but not turned on. Electromyogram, HV angle (HVA) at rest and during abduction of the big toe, and strength of the AbdH were evaluated. Analysis of covariance was used to investigate differences within groups using the baseline as the covariate. NMES significantly improved the maximal voluntary isometric contractions (%MVIC), HVA at exercise, and muscle strength (%MVIC: p = .00, HVA exercise: p = .00, AbdH strength: p = .00). HVA at rest showed no change (p = .12). Application of NMES on the AbdH muscle immediately improved its activity output, muscle strength, and HVA during exercise.

Effect of Capacitive and Resistive electric transfer on changes in muscle flexibility and lumbopelvic alignment after fatiguing exercise.

[Purpose] This study aimed to clarify the effects of Capacitive and Resistive electric transfer (CRet) on changes in muscle flexibility and lumbopelvic alignment after fatiguing exercise. [Subjects and Methods] Twenty-two healthy males were assigned into either the CRet (n=11) or control (n=11) group. Fatiguing exercise and CRet intervention were applied at the quadriceps muscle of the participants' dominant legs. The Ely test, pelvic tilt, lumbar lordosis, and superficial temperature were measured before and after exercise and for 30 minutes after intervention. Statistical analysis was performed using one-way analysis of variance, with Tukey's post-hoc multiple comparison test to clarify within-group changes and Student's t-test to clarify between-group differences. [Results] The Ely test and pelvic tilt were significantly different in both groups after exercise, but there was no difference in the CRet group after intervention. Superficial temperature significantly increased in the CRet group for 30 minutes after intervention, in contrast to after the exercise and intervention in the control group. There was no significant between-group difference at any timepoint, except in superficial temperature. [Conclusion] CRet could effectively improve muscle flexibility and lumbopelvic alignment after fatiguing exercise.

Relationship between transverse arch height and foot muscles evaluated by ultrasound imaging device.

[Purpose] Few studies on the transverse arch (TA) in the forefoot have been conducted. The forefoot is where pains occur most frequently and is related to walking and balance; hence, paying attention to TA is vital. However, the relationship between TA and foot muscles has not been investigated. Therefore, this study aims to investigate muscles related to TA. [Subjects and Methods] Nineteen healthy young males were included. Measurements of their feet, excluding one foot with recent foot pain (n=37), were obtained. The height of TA (TAH) was measured in two ways: during 10% and 90% loading of body weight. The cross-sectional area and thickness of five muscles were measured: flexor digitorum longus, peroneus longus and brevis, flexor hallucis brevis, flexor digitorum brevis (FDB) and abductor hallucis (ABH). All measurements were performed with an ultrasound device. [Results] FDB and ABH were correlated with TAH during 10% and 90% loading after removing the effect of body mass index and age. The greater FDB and ABH, the higher TAH. [Conclusion] As FDB becomes larger, the second, third and fourth metatarsal heads are raised more. Furthermore, the height of the first metatarsal head is lowered by a larger ABH. These mechanisms may increase TAH.

Relationship between agility and lower limb muscle strength, targeting university badminton players.

[Purpose] Targeting university badminton players, this study investigated the relationship between agility, which is associated with performance in badminton, and lower limb muscle strength, and examined which muscles influence agility. [Subjects and Methods] A total of 23 male university badminton players were evaluated for side-shuffle test scores and lower limb strength. The relationships between agility, lower limb strength, and duration of experience playing badminton were evaluated using a correlation analysis. Moreover, the relationship between agility and lower limb strength was evaluated by partial correlation analysis, adjusting for the effects of experience of each badminton player. [Results] The agility score correlated with hip extension and ankle plantar flexion strength, with adjustment for badminton experience. [Conclusion] This study suggests that hip extension training and improvement in ankle plantar flexion strength may improve agility.

9,10-Phenanthrenequinone promotes secretion of pulmonary aldo-keto reductases with surfactant.

9,10-Phenanthrenequinone (9,10-PQ), a major quinone in diesel exhaust particles, induces apoptosis via the generation of reactive oxygen species (ROS) because of 9,10-PQ redox cycling. We have found that intratracheal infusion of 9,10-PQ facilitates the secretion of surfactant into rat alveolus. In the cultured rat lung, treatment with 9,10-PQ results in an increase in a lower-density surfactant by ROS generation through redox cycling of the quinone. The surfactant contains aldo-keto reductase (AKR) 1C15, which reduces 9,10-PQ and the enzyme level in the surfactant increases on treatment with 9,10-PQ suggesting an involvement of AKR1C15 in the redox cycling of the quinone. In six human cell types (A549, MKN45, Caco2, Hela, Molt4 and U937) only type II epithelial A549 cells secrete three human AKR1C subfamily members (AKR1C1, AKR1C2 and AKR1C3) with the surfactant into the medium; this secretion is highly increased by 9,10-PQ treatment. Using in vitro enzyme inhibition analysis, we have identified AKR1C3 as the most abundantly secreted AKR1C member. The AKR1C enzymes in the medium efficiently reduce 9,10-PQ and initiate its redox cycling accompanied by ROS production. The exposure of A549 cells to 9,10-PQ provokes viability loss, which is significantly protected by the addition of the AKR1C3 inhibitor and antioxidant enzyme and by the removal of the surfactants from the culture medium. Thus, the AKR1C enzymes secreted in pulmonary surfactants probably participate in the toxic mechanism triggered by 9,10-PQ.

Effects of a DVD-based seated dual-task stepping exercise on the fall risk factors among community-dwelling elderly adults.

OBJECTIVE: The purpose of this randomized control trial study was to evaluate the effectiveness of a digital video disc (DVD)-based seated dual-task (DT) stepping exercise to improve the DT walking capability in elderly people. In the DT exercise, participants were asked to perform a verbal fluency task while stepping as quickly as possible. METHODS: Eight clusters (n=93) randomized into a DVD group (4 clusters, n=48) and a nonexercise control group (4 clusters, n=45) participated in this trial. In the DVD group, participants received 20 min of group training twice a week for 24 weeks. The exercise class used an exercise DVD that included a 15-min basic exercise and a 5-min DT exercise. No exercise program was prescribed for the control group. The measurements were based on the difference in physical function, including DT walking, between the DVD and control groups. In the DT walking test, participants walked individually at a comfortable speed while carrying a ball on a tray. The relative DT lag was calculated by using simple walking as the comparison condition. The Timed Up and Go test and the 5-chair stand test were also performed. RESULTS: The median relative adherence to the study was 87.5% (25th-75th percentile, 83.3%-95.8%) in the DVD group. The outcome measurements, including the DT walking time and DT time lag (p<0.05), among participants in the DVD group were significantly improved. However, other outcome measurements were not significantly different between the two groups (p>0.05). CONCLUSION: The current study reports the effectiveness of a DVD-based exercise for the improvement of the DT walking capability. A larger study is needed to confirm the present results. Study of a Web-based exercise regime would be valuable to identify the most effective exercise for prevention of falls and fall-related fractures.