To investigate whether muscle fiber conduction velocity reflects muscle fiber type, we studied the extensor digitorum longus (EDL) and soleus (SOL) muscle in 7 male rats aged 12 weeks. Muscle fiber conduction velocity was measured with a surface electrode array during stimulated contraction and calculated from the delay between two action potentials along muscle fibers for a given inter-electrode distance. Conduction velocity in the EDL (2.71±0.50 m/s) was significantly higher (p<0.05) than that in the SOL (2.14±0.34 m/s) . Fiber type, fiber area and fiber diameter were determinated by myosin ATPase staining and NADH-tetrazolium reductase staining. Muscle fiber composition of the EDL and SOL was 94.6±1.8 and 14.8±4.3% FT fibers, respectively, and mean muscle fiber diameter was 62.7±6.2 pm and 79.2±7.8pm, respectively, that of the EDL being significantly smaller (p<0.01) than that of the SOL. It was suggested that individual differences in conduction velocity were caused by differences in muscle fiber composition rather than differences in muscle diameter.

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A study was conducted to examine the relationship between percent body fat (%fat) and medical examination parameters. The subjects were 250 women aged 17 to 68 years, who neither drank nor smoked. The results obtained were as follows:
After controlling for the effects of age and maximal oxygen intake per kilogram body weight (VO₂max/wt), %fat showed a significant correlation with high-density lipoprotein cholesterol (HDL-C), total cholesterol/HDL-C ratio (TC/HDL-C), β-lipoprotein (β-L), glutamic oxaloacetic transaminase (GOT), glutamic pyruvic tansaminase (GPT), uric acid (UA), white blood cell count (WBC), red blood cell count (RBC), systolic blood pressure (SBP), and diastolic blood pressure (DBP) . Values of %fat calculated from each regression equation when HDL-C=38mg/dl, TC/HDL-C=4.9, β-L=500 mg/dl, GOT=41mu/ml, GPT=46 mu/ml, UA=5.7mg/dl, WBC=8500/mm3, RBC=520×104/mm3, SBP=159 mmHg, and DBP=94 mmHg were 32.2%, 31.9%, 30.8%, 35.4%, 36.4%, 31.8%, 30.7%, 35.0%, 33.8% and 32.6%, respectively.
The subjects were then divided into 2 groups, above (above group) or below (below group) 30%, 31%, 32%, 33%, 34% or 35% body fat. Wherever the subjects were divided into 2 groups at these values of %fat, the above group showed a significantly higer occurrence of abnormal values for medical parameters than the below group.
The subjects were further divided into 3 groups: 154 subjects with %fat below 29.9% (N group), 47 subjects with %fat between 30% and 34.9% (MO group), and 49 subjects with %fat above 35% (O group) . The O group showed significantly higher occurrence of abnormal values for medical parameters than the MO and N groups. The O group also showed a significantly higher mean value of DBP than the MO and N groups. Furthermore, the O group showed a significantly lower mean value of HDL-C and significantly higher mean values of TC/HDL-C, UA, GOT, GPT, SBP, FBS than the N group. There was no significant difference between the N and MO groups in the occurrence of abnormal values for medical parameters. However, the MO group showed a significantly lower mean value of HDL-C and significantly higher mean values of TC/HDL-C, UA and β-L.
These results suggest that the values of medical parameters become poorer when %fat exceeds 30%, a level widely used in Japan as a criterion for evaluation of obesity.
The subjects were further divided into 3 groups: 50 subjects who were non-obese and fit (NF group) ; 104 subjects who were non-obese and unfit (NU group) ; 88 subjects who were obese and unfit (OU group) . There were significant differences in the occurrence of abnormal values for medical parameters among these groups. The NF group showed the lowest values, followed by the NU and OU groups. Thus, it seems preferable to evaluate individuals using a combination of %fat and VO₂max/wt.

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In order to prevent sports anemia, caused especially by iron deficiency or shortage, a special type of food supplementation was designed. This was called“iron-food”and contained 510% of the therapeutic iron dose. According to hemoglobin (Hb) values, female subjects who had been performing hard daily training were divided into two groups ; an anemia group (A group, Hb≤11.9 g/dl, n=4) and a potential anemia group (PA group, 12.0≤Hb≤12.9g/dl, n=4) . Then the iron-food was administered for six weeks following placebo treatment. Iron status, hematological profiles and aerobic work capacity of the two groups were examined before and after the two periods to investigate the effect of the iron-food. Serum iron, iron saturation and ferritin were significantly increased in the PA group. Serum iron tended to be increased in the A group, but not significantly. Red blood cell count, Hb and hematocrit were significantly increased in the PA group, and the reticulocyte count was also increased in the A group. These results suggest that iron-food helped to increase daily iron intake in the anemic subjects, but not to a sufficient extent to aid recovery from anemia. However the ironfood was effective for improving iron status in subjects with potential anemia (latent iron deficiency) .

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A study was couducted to determine the changes in urinary 3-methylhistidine (3-ME), urea-nitrogen (Urea-N) and creatinine (CR) in the initial period of weight training. The urinary excretion of 3-ME, Urea-N and CR over a 24-h period in nine human subjects was determined before and during (at one-day intervals) a weight training period of 11 days. Two periods of weight training at different work intensities were performed; experiment A (Exp. A) : three sets of 8 repetitions at 60% of maximal voluntary contraction (MVC) ; experiment B (Exp. B) : one set of 48 repetitions at 30% of MVC. Subjects in both Exp. A and Exp. B performed five kinds of weight lifting exercise (hyper extension, sit-up, bench press, leg curl, leg extension) every day during the weight training period.
The main results obtained were as follows;
1) Urine volume and urinary CR showed no clear changes in either Exp. A or Exp. B.
2) In Exp. A, urinary 3-ME increased significantly, and Urea-N tended to decrease during the weight training period. On the other hand in Exp. B, urinary Urea-N tended to increase, but the fluctuation of urinary 3-ME showed no clear tendency during the weight training period.
3) After the weight training period, girth of the chest, upper arm and thigh tended to be increased after Exp. A in comparison with those before the weight training period.
These results suggest that whole-body protein catabolism in the initial period of weight training is dependent on the aim and type of weight training.

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The relationship between arterial blood pressure and accelerated plethysmogram (APG) obtained by differentiating two times digital plethysmogram was studied in five healthy male university students. Finger arterial blood pressure was found to change by inflating the cuff of a sphygmomanometer placed on the upper arm followed by gradual deflation. APG and blood pressure were analyzed in the beat by beat mode. Room temperature was maintained at 23-24°C.
The following results were obtained :
1) Component“a”of APG became higher, and“b”and“e”components became increased with systolic blood pressure (SBP) .
2) Component“a”of APG decreased, as did also“b”and“e”components with increase in diastolic blood pressure (DBP) and arteriolar elasticity.
3) The two mechanisms for increase in SBP were increase in blood volume, and increase in peripheral resistance. The wave pattern of APG (A-G) changed from G to A by the former, and A to G by the latter.
These findings clearly show the relationship between APG and arterial blood pressure depend on the particular mechanism involved. The simultaneous mesurement of APG and blood pressure may serve as a useful means for measuring peripheral hemodynamics.

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A study was conducted to investigate muscle fatigue during isometric contraction of the indicis proprius using EMG analysis (BIMUTAS Ver. 2. 1) .
The subjects were 8 healthy men (ranging in age from 19 to 42 years) .
Plummets (ranging from 300g to 600g) were placed on the distal knuckle of the index finger to create loads on the indicis proprius muscle. EMG was recorded until the plummet dropped, and the total time required was divided into 10 equal parts. In each part, the EMG record for the first 1000 ms was picked out. Then the mean power frequency (MePF) and median power frequency (MdPF) of the power spectrum were calculated.
The results were as follows:
1) Both MePF and MdPF showed shits to lower frequency bands.
2) Integrated values of the EMG power spectrum increased with time.
3) The time courses of the MePF and MdPF in each EMG sample for the 8 subjects were determined by the 3-point moving average method.
A break-point was observed in each MePF and MdPF diagram.
It was considered that two-break points observed in the time courses of the EMG record were valid as an objective index of local muscle fatigue.

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A study was conducted to determine whether anticipation of exercise alters the responses of sympathetic nerve activity to muscle contraction. Sympathetic nerve activity leading to the skin (SSA) and muscle (MSA) was recorded from the tibial nerve in the left and right legs using tungsten microelectrodes. Heart rate and blood pressure (oscillometric method) were also measured during the experiment. Seven healthy subjects, who gave informed consent, participated in the experiment. They were asked to exert a static handgrip (SHG) for 2 min at a tension of 30% of maximal voluntary handgrip. Two different situations were set before the commencement of exercise. One was that after several minutes of controlled rest, a countdown was started 2 min before the exercise, and then the handgrip was applied (Cond. 1) . The other was that a preparation time of between 7 and 5 min was set prior to the handgrip exercise while no information regarding the starting time of exercise was given to the subjects (Cond. 2) . SSA for 30 s just before the exercise was increased in comparison with the control value at rest in Cond. 1, but not in Cond. 2. There was no difference in the SSA response patterns to SHG between the two conditions. Before the commencement of SHG, MSA did not alter from the control value at rest in either condition. The magnitudes of the increase in MSA during SHG were almost identical under both conditions. Heart rate for 30s before SHG in Cond. 1 was increased significantly from the control value, whereas there was no significant change in Cond. 2. The magnitude of the heart rate response to SHG was the same in both conditions. The mean blood pressure showed no significant change before SHG, but increased significantly during SHG in both conditions. The increases in SSA and heart rate prior to the commencement of exercise may be related to the anticipatory response to the exercise, although this response was not significant in MSA. These results confirm that anticipation of exercise increases sympathetic outflow to the skin. This may be advantageous in adapting the body to exercise.

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