The purpose of this study was to clarify the effects of bicycle ergometer training and prostaglandin E₁ (PGE₁) for patients with intermittent claudication. Subjects were divided into four groups : the medication group (M), the PGE₁ group (P), the exercise group (E) and the PGE₁ and exercise group (PE). The P group was injected with 10μg of PGE₁, the E group performed bicycle ergometer exercise 3 times a week for 6 weeks, and the PE group was injected with PGE₁ and performed exercises. The maximal walking distance (MWD) was evaluated by a treadmill test. Muscle oxygenation level was measured by near-infrared spectroscopy and recovery half time (T_1/2) was calculated. MWD was significantly improved for P (142%), E (216%) and PE (240%) groups. T_1/2 was significantly improved in the E and PE groups. This study indicates that improvement of MWD was a result of development of muscle perfusion in lower limbs and PGE₁ injection may support exercise therapy.

We evaluated regional differences of muscle O₂ dynamics between distal and proximal sites in the vastus lateralis (VL) muscle using near infrared spatial resolved spectroscopy (NIR_SRS). forty-one male subjects performed a 30 W ramp incremental bicycle exercise test until exhaustion. The NIR_SRS probes were attached on each distal and proximal site in the VL. The pulmonary O₂ uptake and heart rate were monitored continuously during the experiment. The TOI at rest was significantly higher in proximal than distal sites (65.0±5.2 vs. 69.7±4.6%, p<0.001). The TOI at exhaustion was also significantly higher in proximal than distal sites (39.5±6.7 vs. 47.5±7.6%, p<0.001). Moreover, a significant correlation was found between VO₂max and the TOI at exhaustion in each proximal and distal site in the VL. Half time reoxygenation, the time to reach a value of half-maximal recovery, was significantly slower in distal sites than proximal sites (27.1±5.6 vs. 25.0±6.1 sec, p<0.01). In conclusion, lower muscle oxygenation at exhaustion in higher VO₂max may be due to enhanced O₂ extraction in high oxidative capacity muscle. In addition, slower reoxygenation and lower muscle deoxygenation at the distal site in the VL may be explained by differences in O₂ supply and/or muscle fiber composition between distal and proximal sites.

The purpose of this study was to determine the age and habitual physical activity on re-oxygenation time in working muscles following maximal cycling exercise (CycEXmax). Twelve sedentary middle-aged (50±6), 13 sedentary elderly (66±3), 13 active middle-aged (53±5), and 20 active elderly (67±5) were evaluated the half re-oxygenation time (T1/2 reoxy) as an index of oxygen delivery, using near-infrared spectroscopy at the vastus lateralis (VL) and lateral head of the gastrocnemius (LG) after CycEXmax. T1/2 reoxys at VL and LG were significantly greater in the elderly subjects than in the middle-aged subjects in both sedentary and active groups. T1/2 reoxys at VL and LG of the active group were smaller than those of the sedentary group, regardless of age. The results of this study suggest that habitual physical activity may attenuate age-related prolongation in T1/2 reoxy in working muscles although ageing delay T1/2 reoxy in working muscles.

The aim of the present study is to clarify the improvement of peripheral muscle oxygen consumption after successful renal transplantation. We investigated change of forearm (brachioradial muscle) muscular oxygen consumption in chronic renal failure children before and after renal transplantation. by using near-infrared spectroscopy.Oxygen consumption of brachioradial muscle was increased significantly after succesful renal transplantation. And half recovery time of brachioradial muscle oxygenation in arterial occlusion and exercise were decreased after renal transplantation.These results suggest that increased muscular blood flow and increased oxidative generation of ATP might contribute to the increased oxygen turn over after renal transplantation.

The purpose of this study was to compare changes in oxygenation in the Vastus Lateralis (VL) and Rectus Femoris (RF) muscles during a ramp-loaded bicycle exercise. Twelve healthy males participated in the experiment. The test consisted of a leg arterial occlusion at rest and a ramp-loaded exercise (20 watts/min) using a bicycle ergometer until exhaustion. The changes in deoxygenation in each muscle was measured by near infrared spectrometer (NIRS) . The probes of NIRS were placed on VL and RF approximately 12 cm above the right knee. Oxy-Hb/Mb signals from NIRS were calculated as 100% at rest, with 0 % being the lowest value during the leg arterial occlusion. Pulmonary gas exchanges (VE, VO₂, VCO₂) were measured with an expiratory gas analyzer. In 10 subjects, muscle oxygenation level in VL decreased linearly until the deoxygenation limiting point (DOLP) -the point in exercise at which the deoxygenation rate decreases noticeably. However, in 2 subjects, the DOLP was not detected, and the muscle oxygenation level decreased linearly until exhaustion. The muscle oxygenation level in RF also decreased linearly until 70%VO₂max, although the deoxygenation rate was smaller than that in VL. Thereafter, the muscle oxygenation level in RF continued to decrease until exhaustion. No DOLP was found in any subjects in RF. Compared with the muscle oxygenation level in RF at any points during the exercise, those in VL were lower until 90%VO₂max (P<0.001) . However, the difference in muscle oxygenation levels between VL and RF at exhaustion was not noted. This study indicated that the patterns of deoxygenation in VL and RF during a ramploaded bicycle exercise were different.

The purpose of this study was to investigate the relationship between physical fitness and coronary risk factor profiles in Japanese women. The subjects were 1, 483 women (ages 30 to 69) who participated in a practical health promotion program. After medical examination, physical fitness was evaluated by conducting a symptom limited maximal exercise test by ergometer to measure maximum oxygen uptake (peakVO2) with an expired gas analyzer. The subjects were classified into 3 groups (high fitness, moderate fitness, and low fitness) according to age and physical fitness level. The results showed that the subjects in higher fitness groups had lower levels in: body mass index (BMI), percentage of body fat, waist−hip ratio, resting blood pressure, and atherogenic index, and higher HDL−cholesterol compared to those in lower fitness group. Even after adjustment for the effects of age and BMI, the subjects in the higher fitness groups had better coronary risk factor profiles. These results suggest that among Japanese women a high level of physical fitness is related to favorable coronary risk factor profiles.
Physical Fitness ; Risk Factors ; Japanese language ; Cardio- ; Human Females

To elucidate the phenomenon of central fatigue, we investigated the changes in the plasma amino acid level and false neurotransmitter (FNT) level during ultra-endurance exercise. Twenty-one male Japanese participants of the 1993 Ironman Japan Contest, held at Lake Biwa, were examined. Blood sampling and a questionnaire on the Profile of Mood States (POMS) test were collected two days before, immediately after and one-day following the race. The POMS questionnaire showed various changes especially due to fatigue. Indeed, the fatigue score significantly increased after the race. Although the confusion score significantly increased after the race, it quickly recovered to the pre race level the following day. The plasma concentration of the branched-chain amino acids (BCAA) decreased after the race, while the level of aromatic amino acids (AAA) increased, thus resulting in a significant decrease in the BCAA/AAA ratio. The plasma level of octopamine, one type of FNT, significantly increased after the race (p<0.01) . The blood ammonia level increased after the race, but recovered to the pre-race level one-day after the race. Although no change was observed in the total tryptophan (Trp) level, the level of free Trp significantly increased during the race. The significant increases in the plasma 5-hydroxyindoleacetic acid (5HIAA), homovanillic acid (HVA) and HVA/dihydroxyphenylacetic acid (DOPAC) ratios thus suggest the serotonin (5 HT) and dopamine (DA) neuron systems activated after the race. In conclusion, ultra-endurance exercise caused a disorder of both the amino acid and monoamine metabolisms. Furthermore these changes were also related with mood changes, especially fatigue, i. e. central fatigue. These results suggest that the measurement of both the plasma BCAA/AAA ratio and FNT may therefore be useful in quantifying exercise induced central fatigue.