We attempted to propose the equation of assessing the functional status of elderly adult Japanese men. A number of physical and motor performance measurements were collected from a group of 104 male volunteer subjects (mean age 76.4 ± 5.8 years). Factor analysis with varimax criterion was applied to all the data. Five factors extracted were interpreted as follows: (1) coordination of the body, (2) flexibility of the trunk, (3) static balance, (4) muscular strength and endurance, and (5) cardiorespiratory fitness. Furthermore, the factor score was computed for each individual by each factor. Each of the five factors were weighted in accordance with its relative contribution to the total variance (or the size of eigenvalue). The weighted combination of factor scores was summed to generate an index of functional status (IFS). Next, IFS scores were computed for each individual and normalized to T scores. Then, a multiple linear regression analysis was performed with the factor analytically derived IFS scores as the dependent variable: IFS=-0.625X1+0.604X2+0.346X3+0.223X4+0.465X5+0.082X6+0.114X7+0.199X8 + 0.019X9 + 0.071X10+19.76; where Xl=walking around two chairs in a figure 8 (sec), X2=manipulating pegs in a pegboard (num), X3=verticaljump(cm), X4=sit and reach (cm), X5=estimated maximal oxygen uptake (ml/kg/min), X6=balnacing on one leg with eyes open (sec), X7=grip strength (kg), X8=trunk flexion from a standing position (cm), X9= Ieg muscle endurance in a semi-squat position against a wall (sec), and X10 =balancing on one leg with eyes closed (sec)
Subjects were 10 workers (Group R) working in two cold storages (air temperature was between -20°C and -23.2°C ), and eight workers (Group C) working in a general storehouse (air temperature was between 12°C and 15.2°C ). They were all male workers operating forklift-trucks . Average (SE) age for Group R was 41. 4(1.3) years and for Group C was 47.3(1.6) years. Hand tremor, handgrip strength, pinch strength, counting task, flicker value, peak flow rate and blood pressure were measured five times (before work, at 10 a.m., before lunch, at 3 p.m. and after work) per day. Blood samples were collected before lunch. Free fatty acid (FFA) of Group R was significantly higher than that of Group C. There were no significant diffcrences in handgrip strength, pinch strength, counting task, flicker value and peak flow rate between Group R and Group C. However, changes in hand tremor and diastolic blood pressure for Group R were significantly greater than those for Group C. Only for Group R, there was a significant relationship between FFA and the hand tremor values measured the second time. Work loads of Group R would be increased by not only the extreme coldness but also large tempera-ture difference between the inside and the outside of the cold storages. The actual forklift work in these cold storages did not cause a distinct reduction in manual performance, but caused an increase in stress which would be expressed as an increase in catecholamine excretion.
The changes in surface electromyogram(EMG) during sustained contractions were compared between monopolar and bipolar lead. Ten subjects performed static elbow flexion at contraction levels of 10 and 40% of maximum voluntary contraction(MVC). Seven subjects performed static knee extension at contraction levels of 3, 8, and 15%MVC.Surface EMGS were recorded from the biceps brachii, vastus lateralis, rectus femoris and vastus medialis in monopolar and bipolar lead. Mean amplitude of EMG(AEMG) and frequency spectra of EMG were calculated. AEMG was larger in monopolar EMG than in bipolar EMG except 3 cases. AEMG changed more abruptly in bipolar EMG than in monopolar EMG. Relative power in 10w frequencies increased(slowing) during contractions in all cases of monopolar EMG. But bipolar EMG sometimes did not show slowing. Decrease of relative power in low frequencies(quickening) was sometimes seen during contractions. This quickening was not marked in monopolar EMG because of its large slowing. This study shows that obscure EMG slowing during a low-level fatiguing contraction is related to the lead methods. Led amplitude was compared between the lead methods using a simple model. The sphere that EMG reflects(pickup sphere) is larger in monopolar EMG than in bipolar EMG. This difference in the pickup sphere is thought not to be the main reason for the difference in the slowing.
The frequency of body movement in the elderly and young people during sleep was measured in order to investigate the effect of hot thermal environ-ments on sleep in summer. Simultaneously, room temperature and humidity were also measured. In the morning after measuring body movements, the subjects completed a questionnaire about their night's sleep. The results obtained were as follows: 1) The time of going to bed and rising in the elderly was significantly earlier than the young. 2) The elderly had a tendency to judge their sleep as "good", however, there were no significant differences between the two groups. 3) The room temperature for the elderly during sleep ranged from 25 to 28°C(mean 26.5°C). On the other hand, it was between 20 and 30°C (mean 27.1°C) in the young, which was significantly higher than that of the elderly. 4) Body movement in the elderly during sleep was significantly greater than those in the young. 5) A significant relation between body movement and room temperature was found within each group. Under conditions of less than 28°C of room temperature, there were significantly higher rates of body movement in the elderly.