The purpose of this study was to examine the physiological responses and RPE during water walking using the Flowmill, which has a treadmill at the base of a water flume, in order to obtain basic data for prescribing water walking for people of middle and advanced age. Twenty healthy female volunteers with an age of 59.1 ± 5.2 years took part in this study. They belonged to the same swimming club and regularly swam and exercised in water. Walking in water took place in the Flowmill. Subjects completed four consecutive bouts of 4 min duration at progressively increasing speeds (20, 30, 40 and 50 m/min) with 1 min rest between each bout. In addition, water velocity was adjusted to the walking speed of each bout. Subjects were instructed to swing both arms in order to maintain their balance during walking in water. The water depth was to the level of the xiphoid process and the water temperature was 30.31 ± 0.08°C. Both heart rate (HR) and oxygen • uptake (VO2) increased exponentially as walking speed • increased. HR was 125 ± 15 bpm, and VO2 was 18.10 ± 2.72 ml/kg·min -1 during walking in water at 50 m/ min, which was the highest speed. The exercise intensity at this speed was equivalent to 5.2 ± 0.8 Mets. The• relationship between HR and VO2 during walking in water showed a highly significant linear relationship in each subject. There was also a highly significant linear • relationship in the mean HR and VO2 of all subjects. Blood lactate concentration (LA) measured at rest and immediately after each bout was 1.1 ± 0.4 mmol/l at rest, 1.0 ± 0.2 mmol/l at 20 m/min, 1.0 ± 0.3 mmol/l at 30 m/ min, 1.1 ± 0.2 mmol/l at 40 m/min, and 2.4 ± 0.7 mmol/ l at 50 m/min. LA at 50 m/min was significantly higher than at rest and at the other speeds. The relationship between HR and RPE during walking in water showed a highly significant linear relationship. The relationship between walking speed and energy expenditure calculated• from VO2 and the respiratory exchange ratio (R) showed a high significant exponential relationship. These results suggested that HR and RPE can be effective indices for exercise prescription during Flowmill walking as with land walking.

The polymorphic alleles of the human ABO-Secretor locus (FUT2 or Se) show high heterogeneity and overt ethnic specificity. To provide additional data for analysis to elucidate the origins of populations, we have investigated the allelic polymorphism of FUT2 in 40 unrelated Tibetan and 53

This study sought to determine the characteristics of gait patterns and muscle activity in the lower extremities of elderly women during underwater treadmill walking against water flow. Eight female subjects (61.4+/-3.9 y) performed underwater and land treadmill walking at varying exercise intensities and velocities. During underwater walking (water level at the xiphoid process) using the Flowmill, which has a treadmill at the base of a water flume, the simultaneous belt and water flow velocities were set to 20, 30 and 4 m.min(-1). Land walking velocities were set to 40, 60 and 80 m.min(-1). Oxygen uptake and heart rate were measured during both walking exercises. Maximum and minimum knee joint angles, and mean angular velocities of knee extension and knee flexion in the swing phase were calculated using two-dimensional motion analysis. Electromyograms were recorded using bipolar surface electrodes for five muscles: the tibialis anterior (TA), medial gastrocnemius (MG), vastus medialis (VM), rectus femoris (RF) and biceps femoris (BF). At the same exercise intensity level, cadence was almost half that on land. Step length did not differ significantly because velocity was halved. Compared to land walking, the maximum and minimum knee joint angles were significantly smaller and the mean angular velocity of knee extension was significantly lower. Knee extension in the swing phase was limited by water resistance. While the muscle activity levels of TA, VM and BF were almost the same as during land walking, those of MG and RF were lower. At the same velocity, exercise intensity was significantly higher than during land walking, cadence was significantly lower, and step length significantly larger. The knee joint showed significantly smaller maximum and minimum angles, and the mean angular velocity of knee flexion was significantly larger. The muscle activity levels of TA, VM, and BF increased significantly in comparison with land walking, although those of MG and RF did not significantly differ. Given our findings, it appears that buoyancy, lower cadence, and a moving floor influenced the muscle activity level of MG and RF at the same exercise intensity level and at the same velocity. These results show promise of becoming the basic data of choice for underwater walking exercise prescription.

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The purpose of the present study was to determine whether or not the exercise intensity of waterwalking for elderly women could be accurately prescribed by heart rate data obtained during treadmill exercise on land. Six healthy female volunteers, with a mean age of 62.2 ± 4.2 years, took part in this study. Walking on land was performed on a treadmill. Each subject completed three consecutive 4-minute walks at a progressively increasing velocity (40, 60 and 80 m·min -1 ), with a 1-minute rest after both the first and second walks. The room temperature and relative humidity were 24.5 ± 0.2°C and 54.8 ± 4.0%, respectively. Walking in water was performed in a Flowmill, which is a treadmill positioned at the base of a water flume. Each subject completed three consecutive 4-minute walks at a progressively increasing belt and water-flow velocity (20, 30 and 40 m·min -1 ), with a 1-minute rest after both the first and second walks. The water depth was at the level of the xiphoid process of each subject. The water temperature was 30.7 ± 0.1°C. The exercise intensity at the highest workrate was equivalent to 44.2 ± 10.3% of the heart rate reserve (HRR) during water-walking and 38.4 ± 4.7% of the HRR during land-walking. There was a highly significant linear relationship between heart rate (HR) and oxygen uptake (V • O 2 ) during both water-walking and land-walking. The relationship between HR and V • O 2 in both exercise modes was similar. Thus, the relationship of HR to V• O 2 derived from a treadmill-graded walking test on land may be used to prescribe exercise intensity for waterwalking in thermoneutral water.