The influence of gender, athletic events, and athletic experience on the subjective dominant hand and the determination of the dominant hand based on the laterality quotient (LQ) and the validity of the LQ.

This study aimed to reveal the influence of gender, athletic events and athletic experience on the subjective dominant hand and the dominant hand based on the laterality quotient (LQ). It also aimed to examine the validity of the Edinburgh Inventory (Oldfield, 1971). Males and females (n=3,726) living in 7 prefectures in Japan (age: 16-45 yrs) participated in this survey. Analysis was performed on 3,557 separate datasets with high reliability. The reliability of the survey was examined using a test-retest method consisting of 100 people selected randomly from all participants. All participants provided the same answers for each question. The influence of gender, event and experience was examined for the subjective and LQ-based dominant hands. In addition, concordance rates of the subjective dominant hand and the LQ-based dominant hand and both dominant hands were examined. Differences of concordance rates between hands used in the 10 movement questions of the Inventory and the subjective dominant hand were tested using the chi(2) test. The frequency differences among items were tested using Ryan's method (multiple comparisons). Significant gender differences were found between rates of the LQ-based dominant hand (males: 94.4%; females: 96.6%) and the subjective dominant hand (males: 91.6%; females: 94.0%), but the degree was only 2.0-4.0%. Insignificant differences were found among athletic events, two groups of different athletic experience, and gender according to each athletic event. The subjective dominant hand almost always agreed with the LQ-based dominant hand (complete concordance rate=0.96, kappa=0.67). Of the 10 question items, inexperienced answers were found only in the item "Knife (without fork)". The "Toothbrush", "Broom (upper hand)", and "Opening box (lid)" items had significantly lower correspondence with the subjective dominant hand (79.7-87.0%) than the other items (92.1-95.7%). In conclusion, athletic experience appears to have little influence on handedness, although there is a slight gender difference. The subjective dominant hand almost always agrees with the dominant hand based on the Inventory. A more efficient handedness inventory may be constructed by excluding the above 4 items.

Comparison in the effect of linear polarized near-infrared light irradiation and light exercise on shoulder joint flexibility.

OBJECTIVE: This study aimed at comparing the effect of linear polarized near-infrared light irradiation (PL irradiation) and bicycle exercise with 50%HRreserve on the flexibility of the shoulder joint. DESIGN: Placebo-controlled trial. SETTING: Twenty-four healthy young adults (10 males: mean+/-SD, age 20.9+/-3.1 y, height 171.0+/-3.9 cm, body mass 63.4+/-3.5 kg and 14 females: age 21.2+/-1.7 y, height 162.0+/-7.8 cm, body mass 56.2+/-7.2 kg). INTERVENTIONS: PL-irradiation (100%, 1800 mW), placebo-irradiation (10%,180 mW), and light exercise (50%HRreserve) for 10 minutes. OUTCOME MEASUREMENTS AND RESULTS: The shoulder joint angles were measured twice-before and after each intervention. We measured the angles when the right shoulder joint extended forward and flexed backward maximally without support, and analyzed these shoulder joints and range of motion. Trial-to-trial reliability (intraclass correlations) of each joint angle was very high, over 0.98. All joint angles showed significant changes, and values in post-PL-irradiation and postlight exercise were significantly greater than that in postplacebo-irradiation. Shoulder forward flexion and backward extension angles had significantly greater change rates in PL-irradiation and light exercise than placebo-irradiation, and their range of motion angle was in the order of PL-irradiation, light exercise, and placebo-irradiation. CONCLUSIONS: It is suggested that PL-irradiation produces almost the same effect on shoulder joint range of motion as light exercise.

Agreement in depression determination among four self-rating depression scales applied to Japanese community-dwelling elderly.

OBJECTIVE: In this study, we examined the characteristics of depression determination using four representative self-rating depression scales (Geriatric Depression Scale, GDS; Self-rating Depression Scale, SDS; Center for Epidermiologic Studies Depression Scale, CES-D; and Carroll Rating Scale, CRS) applied to Japanese community-dwelling elderly. METHODS: Subjects were 563 community-dwelling independent elderly living in twelve prefectures (330 males, 68,9±6.3 yr; 233 females, 68.1±5.8 yr). RESULTS: Depression rates determined using SDS (45.8%) and CES-D (68.6%) were higher than those determined using GDS (5.7%) and CRS (14.7%). Although correlations of depression scale scores among the four scales were significant and comparable (r: 0.61 (GDS vs. SDS, p<0.01) to 0.78 (SDS vs. CES-D, p<0.01)), the agreement in depression determination varied among scales (kappa coefficients: 0.05 (GDS vs. CES-D, p>0.05) to 0.46 (SDS vs. CES-D, p<0.01)). CONCLUSIONS: Similarities in depression determination were found between GDS and CRS, and between CES-D and SDS. Depression rates determined on the basis of cut-off point for each scale were higher for CES-D and SDS than for GDS and CRS. Depression determination using a four-point rating scale may overestimate a slightly depressive symptom, compared with that using a two-point scale.

Body sway characteristics during static upright posture in healthy and disordered elderly.

This study aimed to compare body sway characteristics of the healthy elderly and the disordered elderly. The subjects were 38 healthy elderly and 24 disordered elderly with disequilibrium. The latter consisted of two groups: 12 elderly with vestibular organ or central nervous systems disorder (central nervous disorders), and 12 elderly with disorder in other systems (other disorders). The measurement device can calculate the center of foot pressure (CFP) of vertical loads from the values of three vertical load sensors, which are located at the corners of an isosceles triangle on a level surface. The data sampling frequency was 20 Hz. Four body sway factors with high reliability (unit time sway, front-back sway, left-right sway, and high frequency band power) were used to evaluate body sway. As compared with healthy people, central nervous disorders had larger unit time sway, high frequency band power, and left-right sway factors. Other disorders were larger in unit time sway and high frequency band power factors. Central nervous disorders, as compared with other disorders, had larger unit time sway and left-right sway factors. Disorders produced large and fast sway, and central nervous disorders in particular showed a marked sway in the left-right direction. The existence of disease influenced body sway more than decline in various functions related to posture control with aging, because even with the same elderly, disorders showed a larger body sway.

Effect of amino acid mixture intake on physiological responses and rating of perceived exertion during cycling exercise.

This study examined the effects of an amino acid mixture supplement on physiological response and ratings of perceived exertion during submaximal cycle-ergometer exercise in 15 healthy, untrained male students. Subjects performed submaximal sustained exercise (oxygen uptake at anaerobic threshold: 54.6 +/- 12.5% of maximum oxygen uptake capacity) with a cycle-ergometer ride for 60 min. after resting for 1 min. and unloaded cycling for 2 min. They drank either a 380-ml supplement containing vespa amino acids or a lemon-flavored placebo at 30 min. before starting exercise in a double-blind design. The subjects participated in both experiments over a 1-wk. interval. Oxygen uptake, respiratory exchange ratio, heart rate, ratings of perceived exertion, and plasma lactate concentration were measured during the exercise. The change-rate of respiratory exchange ratio for the Supplement group was significantly lower than that for the Placebo group at 10 min. after starting exercise. The change-rate of the ratings of perceived exertion for the Supplement group was significantly lower than that for the Placebo group at 50 min. after starting exercise. There were no significant changes in the rates in oxygen uptake, heart rate, and plasma lactate concentration between groups. We inferred that ingesting the supplement before starting exercise has a significant effect on the respiratory exchange ratio and ratings of perceived exertion during submaximal sustained exercise for 60 min. but not on oxygen uptake, heart rate, and plasma lactate concentration.