Journal of PHYSIOLOGICAL ANTHROPOLOGY (J Physiol Anthropol )

Publisher: Nihon Seiri Jinrui Gakkai


Journal of the Japan Society of Physiological Anthropology.

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    Journal of physiological anthropology (Online), JPA
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    Internet Resource, Computer File, Journal / Magazine / Newspaper

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study was to evaluate the effect of a cool environment on the peripheral skin blood flow and subjective thermal sensations of female office workers and female students. The subjects were 26 female bank employees (mean age, 38 years) who worked in a cool environment and 10 female college students (mean age, 22 years). The peripheral skin blood flow was measured using a laser Doppler blood flow meter. In each bank employee, peripheral skin blood flow was measured at three time points during the workday in the medical treatment room at their workplace. In the college students, peripheral skin blood flow was measured every hour between 9:00 and 17:00 in a laboratory. In both the medical treatment room and the laboratory, the room temperature was controlled at 24-26 degrees C with a relative humidity of 55+/-10%. The bank employees and students were each divided into those with hypersensitivity to cold (Group A) and those without hypersensitivity to cold (Group B). When the 10 college students were in the cool environment (24-26 degrees C), their peripheral skin blood flow generally decreased over time. The rate of decrease of this blood flow was greater in Group A than in Group B. In the female bank employees, the peripheral skin blood flow was the lowest at 12:00 (before lunch), was increased at 13:00 (after lunch), and then was decreased at 17:30. However, the degree of the increase from before lunch to after lunch in Group A was about half of that in Group B. Among female office workers and students, a cool environment reduced the peripheral skin blood flow of individuals with hypersensitivity to cold to a greater degree than in those without hypersensitivity to cold.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 06/2008; 27(3):153-9.
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    ABSTRACT: We have previously reported that there may be a relationship between bowel habits including functional constipation (FC) and irritable bowel syndrome and sleep health. However, our previous studies were based on only subjective parameters by self-reported questionnaire. The aim of this study is to investigate the relationship between bowel habits such as FC and sleep health using objective parameters. Sleep health was assessed by actigraphy measurement and bowel habits by fecal flora analysis. The FC and control subjects, whose bowel habits were defined at Rome II, were recruited from evaluated respondents in our previous study directed at middle-aged Japanese women, ten FC and ten control subjects participating in this study. Wake after sleep onset (WASO) and WASO (%) (WASO/total sleep time multiplied by 100) in FC subjects was significantly longer and greater than those in control subjects, respectively. Average activity during sleep in FC subjects was significantly higher than that in control subjects. FC had no effect on total sleep time. Bifidobacterium is broadly accepted to be useful intestinal bacteria for human health and one of the indices showing that the intestinal environment is in a desirable condition. Bifidobacterium counts per gram of wet feces and proportion in total bacterial cell counts in FC subjects were significantly lower than those in control subjects. In conclusion, these results suggest that corresponding to low Bifidobacterium counts and proportion, sleep in FC subjects may be worse than that in control subjects. There may be a relationship between bowel habits and sleep health. Bowel habits such as FC might be a risk factor for sleep disorders.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 06/2008; 27(3):145-51.
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    ABSTRACT: It has been reported that oxygen uptake (VO2) increases exponentially with levels of the pedal rate during cycling. The purpose of this study was therefore to test the hypothesis that the O2 cost for internal power output (Pint) exerted in exercising muscle itself would be larger than for an external power output (Pext) calculated from external load and pedal rate during cycling exercise under various conditions of Pint and Pext in a large range of pedal rates. The O2 cost (DeltaVO2/ Deltapower output) was investigated in three experiments that featured different conditions on a cycle ergometer that were carried out at the same levels of total power output (Ptot; sum of Pint and Pext) (Exp. 1), Pext (Exp. 2) and load (Exp. 3). Each experiment consisted of three exercise tests with three levels of pedal rate (40 rpm for a lower pedal rate: LP; 70-80 rpm for a moderate pedal rate: MP; and 100-120 rpm for a higher pedal rate: HP) lasting for 2-3 min of unloaded cycling followed by 4-5 min of loaded cycling. Blood lactate accumulations (2.3-3.4 mmol l(-1)) at the HP were significantly higher compared with the LP (0.6-0.9 mmol l(-1)) and MP (0.9-1.0 mmol l(-1)) except for the LP in Exp. 1. The VO2 (360-432 ml min(-1) for LP, 479-644 ml min(-1) for MP, 960-1602 ml min(-1) for HP) during unloaded cycling in the three experiments increased exponentially with increasing pedal rates regardless of Pext=0. Moreover, the slope of the VO2-Pint (13.7 ml min(-1) W(-1)) relation revealed a steeper inclination than that of the VO2-Pext (10.2 ml min(-1) W(-1)) relation. We concluded that the O2 cost for Pint was larger than for Pext during the cycling exercises, indicating that the O2 cost for Ptot could be affected by the ratio of Pint to Ptot due to the levels of pedal rate.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 06/2008; 27(3):133-8.
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    ABSTRACT: The relationship between fat-free mass (FFM) and excess post-exercise oxygen consumption (EPOC) has not been well researched because of the relatively small number of subjects studied. This study investigated the effects of FFM on EPOC and EPOC/maximum oxygen consumption. 250 Japanese male athletes between 16 and 21 years old from Nagasaki prefecture had their EPOC measured up to 40 minutes after short-duration exhaustive exercise. The value was named as EPOC40 min. The proportions of EPOC up to 1, 3, 6, 10, and 25 minutes to EPOC40 min were calculated and named as P1, P3, P6, P10, and P25, respectively. Body size and composition, VO2max and resting metabolic rate (RMR) were also measured. Mean EPOC40 min was 9.04 L or 158 ml/kg FFM. EPOC40 min was related to FFM (r=0.55, p<0.001) and VO2max (r=0.37, p<0.001). The ratio of EPOC40 min to VO2max was related to FFM (r=0.28, p<0.001). P1, P3, P6, P10, and P25 were negatively related to EPOC40 min/FFM, EPOC40 min/VO2max, and FFM. Athletes who had larger FFM had larger EPOC40 40 min and EPOC40 40 min/VO2max, and smaller P1, P3, P10, and P25.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 06/2008; 27(3):139-43.
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    ABSTRACT: The purpose of this study was to investigate the influence of the force tremor (FT) on mechanomyographic (MMG) signals recorded by a condenser microphone (MIC) and an accelerometer (ACC) during measurement of agonist and antagonist muscles in sustained isometric contractions. Surface electromyographic (EMG) signals and MMG signals by MIC (MMG-MIC) and ACC (MMG-ACC) were recorded simultaneously on biceps brachii (BB) and triceps brachii (TB). Following determination of the isometric maximum voluntary contraction (MVC), 10 male subjects were asked to perform sustained elbow flexion and extension contractions at 30% MVC until exhaustion. We analyzed the root mean square (RMS) for all signals and compared the sum of the power spectrum (SPA) for 3-6 Hz and 8-12 Hz and the ratio of the sum of SPA for 3-6 Hz and 8-12 Hz in SPA for 3-100 Hz (SPA-FT/SPA-(3-100 Hz)) between MMG-MIC and MMG-ACC. During all sustained muscle contractions, the RMS of EMG and MMG-(MIC) was significantly (p<0.05) increased in antagonistic muscle pairs, while the increase was more noticeable for the agonist than for the antagonist. In addition, the antagonist had a significantly (p<0.05) smaller amplitude than the agonist muscle. The RMS of MMG-ACC, however, showed no significant (p>0.05) difference in RMS amplitude and slope between agonist and antagonist muscles during flexion. In extension, the MMG-ACC-RMS amplitude showed a tendency to be higher in the antagonist than in the agonist, while their slopes showed no significant (p>0.05) difference. The SPA for 3-6 Hz and 8-12 Hz in MMG-(MIC) showed a tendency to be higher in the agonist than the antagonist, and the slopes of the agonist were significantly (p<0.05) higher than those of the antagonist in all contractions. In MMG-ACC, SPA and slopes for 3-6 Hz and 8-12 Hz tended not to differ between agonist and antagonist. The SPA-FT/SPA-(3-100 Hz) in MMG-ACC showed that the antagonist was higher than that of the agonist in all contractions. The MMG-(MIC), however, showed a tendency toward no difference between the agonist and antagonist. In the assessment of muscle activity during simultaneous measurement of the agonist and antagonist during sustained muscle contractions, the MMG signal detected by MIC appeared to be less affected by FT than by ACC due to the different inherent characteristics of the two transducers.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 06/2008; 27(3):121-31.
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    ABSTRACT: The aim of the present study was to determine whether oxygen supply to non-exercised muscle during recovery following fatiguing exercise is influenced by accumulated metabolites within exercised muscle. Twelve healthy male subjects performed 2-min isometric handgrip exercise at 40% maximal voluntary contraction with their right hand and the exercise was followed by a 3-min recovery period. Muscle oxygen saturation (SmO(2)) determined by near-infrared spatially resolved spectroscopy was used as an index of oxygen supply to non-exercised muscle and was measured in biceps brachii and tibialis anterior muscles on the left side. Compared to the pre-exercise baseline level, SmO(2) in the biceps brachii muscle (SmO(2BB)) increased significantly from 30 sec to 1 min after the start of exercise, while SmO(2) in the tibialis anterior muscle (SmO(2TA)) remained stable during the initial 1 min of exercise. Both SmO(2BB) and SmO(2TA) began to decrease at about 1 min and continued to decrease thereafter. Due to the initial increase in SmO(2BB), only SmO(2TA) showed a significant decrease during exercise. During recovery, SmO(2BB) did not differ significantly from the pre-exercise baseline level, whereas SmO(2TA) remained significantly lower until about 1.5 min of recovery and then it did not differ significantly from the baseline level. In another bout, subjects performed handgrip exercise of the same intensity, but post-exercise arterial occlusion (PEAO) of the exercised muscle was imposed for 2 min immediately after the end of exercise. During PEAO, SmO(2BB) decreased significantly compared to the baseline level, whereas SmO(2TA) remained significantly lower until the end of PEAO. The significant decrease in SmO(2BB) and the prolongation of decrease in SmO(2TA) by PEAO suggests that the recovery of SmO(2) in the non-exercised arm and leg is mediated by muscle metaboreceptors.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 04/2008; 27(2):83-91.
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    ABSTRACT: This study aimed to examine the effects of room temperature and body position changes on cerebral blood volume, blood pressure and center-of-foot pressure (COP). Cerebral oxygenation kinetics and blood pressure were measured by near infrared spectroscopy (NIRS) and volume-compensation, respectively, in 9 males and 9 females after rapid standing from sitting and supine positions in low (12 degrees C) or normal (22 degrees C) room temperatures. COP was also measured in a static standing posture for 90 s after rapid standing. The total hemoglobin (Hb) decreased just after standing. Blood pressure after standing at normal temperature tended to decrease immediately but at low temperature tended to decrease slightly and then to increase greatly. The decreasing ratio of total Hb and blood pressure upon standing from a supine position at normal room temperatures was the largest of any condition. Total Hb recovered to a fixed level approximately 25 sec after standing from a sitting position and approximately 35 sec after standing from a supine position. All COP parameters after standing tended to change markedly in the supine position compared to the sitting position, especially at normal temperatures. The COP parameters after standing in any condition were not significantly related to the decreasing ratio of total Hb but were related to the recovery time of total Hb after standing. In conclusion, decreasing ratios of total Hb and blood pressure after standing from a supine position at normal temperatures were large and may affect body sway.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 04/2008; 27(2):63-70.
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    ABSTRACT: The purpose of this study was to compare the effects of wearing different kinds of masks on the ear canal temperature, heart rate, clothing microclimate, and subjective perception of discomfort. Ten subjects performed intermittent exercise on a treadmill while wearing the protective masks in a climatic chamber controlled at an air temperature of 25 degrees C and a relative humidity of 70%. Two types of mask-mask A, with exhaust valves and mask B, with exhaust holes-were used in the study. The results of this study indicated: (1) The subjects had a tendency toward lower maximum heart rate when wearing mask A than when wearing mask B. (2) Temperatures and absolute humidities (the outer surface of mask, the microclimate inside the mask, the chest wall skin and microclimate) of mask A were significantly lower than those of mask B. (3) The ear canal temperature increased significantly in mask B as compared to that in mask A. (4) The ear canal temperature showed significant augmentation along with increased temperature and humidity inside the mask microclimate. The mask microclimate temperature also affected significantly the chest microclimate temperature. (5) Mask A was rated significantly lower for perception of humidity, heat, breath resistance, tightness, unfitness, odor, fatigue, and offered less overall discomfort than mask B. (6) Subjective preference for mask A was higher. (7) The ratings of subjective overall discomfort showed significant augmentation along with increased wetness and fatigue. We discuss how the ventilation properties of masks A and B induce significantly different temperature and humidity in the microclimates of the masks and the heat loss of the body, which have profound influences on heart rate, thermal stress, and subjective perception of discomfort.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 04/2008; 27(2):93-102.
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    ABSTRACT: The purpose of this study was to determine the body surface area (BSA) based on the alginate method, to derive formulae for estimating BSA, and to compare the error of the present formula to previous formulas obtained from other countries. We directly measured the entire body surface area of 34 males (20-60 years old, 158.5-187.5 cm in height, 48.5-103.1 kg in body weight) and 31 females (20-63 years old, 140.6-173.1 cm, 36.8-106.1 kg) using alginate. The measurements showed that the BSA had a mean of 18,339 cm(2) (15,416-22,753 cm(2)) for males, and 16,452 cm(2) (12,825-22,025 cm(2)) for females. Based on these measurements, a regression model to estimate BSA was derived: Estimated BSA (cm(2))=73.31 Height (cm)(0.725) x Weight (kg)(0.425) (r(2)=0.999). The mean error of the formula was -0.1%, and did not show any significant difference by gender or body shape. When applied to the datasets (n=506) composed of various races (Caucasians, Africans, and Asians), the mean error of the formula was 0.4% and was smaller than that of DuBois & DuBois's, Gehan & George's, and Mosteller's formulas when applied to the same datasets. The errors of the three previous formulas were also within 2%. Overall, formulas based on the DuBois exponent (Weight(0.425) Height (0.725)) did not show any tendency of overestimation or underestimation by body shape, but other BSA-formulae showed differences by body shape. The present BSA formula has shown good accuracy in Korean adults of all weight categories compared to traditional formulas.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 04/2008; 27(2):71-82.
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    ABSTRACT: The aim of this study was to examine the relationship between psychosocial stress and intraocular pressure among apparently healthy subjects. Psychosocial stress among 1,461 public school workers (883 men and 578 women) was measured using the inventory to measure psychosocial stress (IMPS) and intraocular pressure was measured using a non-contact tonometer (Topcon CT-90). After controlling for the effects of likely confounding variables such as age, body mass index (BMI), glycosylated hemoglobin, systolic blood pressure, alcohol consumption, smoking status, and exercise, partial correlations and hierarchical multiple regression analysis were performed in order to test the hypothesis that IMPS-measured stress score was associated with intraocular pressure. IMPS-measured stress score was found to correlate positively with intraocular pressure in women after controlling for the effects of confounding variables, whereas this relationship was not found in men. Hierarchical multiple regression analysis indicated that IMPS-measured stress score was positively associated with intraocular pressure in women independent of confounding variables, but not in men. Perturbations of the hypothalamic-pituitary-adrenal (HPA) axis associated with stress are considered to be partly responsible for an increase in intraocular pressure among people suffering from psychosocial stress. Further research is needed to elucidate the relationship between this stress-associated increase in intraocular pressure and open-angle glaucoma.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 02/2008; 27(1):43-50.
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    ABSTRACT: It is necessary to develop a system of nutritional education which can be understood among schoolchildren who have not yet received a basic education. In the present study, we conducted an educational program for lower-grade schoolchildren, which contained dish selection, an agricultural experience, a cooking experience, and a lecture on digestive absorption. We evaluated the effect of this program on development by measuring taste sensitivity regarding sweet, sour, salty and bitter tastes. For the baseline period, there was no significant difference between the intervention school and the control school in each variable. At follow-up periods, both the intervention and the control schools showed an increasing sense of taste. In the intervention school, development of sensitivity to the sweet, the sour, and the bitter taste was significant. In the control school, development of sensitivity to the sweet and the bitter taste was significant. The increases in the sense of the sour and the bitter tastes and the sum of the four tastes for the intervention subjects were significantly larger than comparable values for the control subjects. These results suggest that the development of taste sensitivity is affected by nutritional education for lower-grade elementary schoolchildren.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 02/2008; 27(1):1-5.
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    ABSTRACT: The purpose of this study was to clarify the fall risk characteristics of the elderly participating in an exercise class. The subjects were comprised of 206 elderly Japanese aged 60 or older (37 males, 169 females) who participated in an exercise class, approved by the local government, once a week for 6 months. Physical fitness and ADL capability were evaluated by the physical fitness test of the Ministry of Education, Culture, Sports, Science and Technology. Fall risk was evaluated using the Fall Assessment Chart. Subjects were divided into two groups, high fall risk (total fall risk score > or =5) and low fall risk (total fall risk score <5), and the percentage of subjects in the high risk group was calculated. The percentage of subjects with a high fall risk was 15.8%, lower than the documented rate of the community-dwelling elderly in a previous study. Significant differences between fall risk groups were found in balance and ADL capabilities of walking, holding and changing posture and muscular strength. These functions also were significantly related to fall risk elements such as fall anxiety and slipping or stumbling at home in the partial correlation analyses. Improvement of these functions during exercise class may be useful in decreasing fall risk in the elderly.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 02/2008; 27(1):25-32.
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    ABSTRACT: Compared to the general population, Parkinson's disease (PD) patients have a higher risk of hip fracture and secondary osteoporosis. In the general population, it is known that physical performance is related to bone density. However, the relationship between bone density and physical performance in ambulatory PD patients has not been studied. This study investigated the relationship between bone density and physical performance in ambulatory PD patients. Fourteen ambulatory PD patients (9 men and 5 women; mean age, 67.3+/-7.7 years; Hoehn & Yahr stages 1-3) were enrolled. Bone density of the right calcaneus was assessed using a speed of sound (SOS) ultrasound measurement device. Disease severity was categorized using the Japanese Unified Parkinson Disease Rating Scale (UPDRS). Furthermore, to assess physical performance, lower extremity strength, 10 m gait time, and body sway were measured. Since SOS is strongly affected by age and gender, it was standardized by the patient's age and gender, and the t-score was calculated with the use of SOS. Significant correlations were found between the t-score and UPDRS,lower extremity strength, and 10 m gait time. When the 4 parts of the UPDRS were analyzed separately, only the correlation between part IV and the t-score was not significant. The findings of this study suggest that higher disease severity and weaker lower extremity physical performance decreased bone density in ambulatory PD patients. Therefore, in order to prevent hip fractures in ambulatory PD patients, assessing the UPDRS and lower extremity physical performance may be clinically useful.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 02/2008; 27(1):7-10.
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    ABSTRACT: Testosterone and estradiol levels were measured by saliva assays in 15 young men, and their relationships with different processes in a mental rotation task were elucidated. The estradiol level was positively correlated with reaction time; this effect was yielded by the slope of functions relating performance to angular disparity. These findings suggest that estrogen may inhibit the performance of a mental rotation task by affecting perception of the rotation process.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 02/2008; 27(1):19-24.
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    ABSTRACT: Deep squatting places a burden on the lower limb muscles and influences postural balance. We attempted to determine the effects of postural changes on the rectus femoris, tibialis anterior, gastrocnemius, soleus, and extensor digitorum brevis muscles during squatting in 8 healthy male subjects. Three squatting conditions were involved: full squatting (FS), tiptoe squatting (TT), and tiptoe squatting on a 15 degrees slope (TTS), performed randomly and recorded in a period of 4 min for each task. The influence of the squatting condition on electromyography and vertical ground reaction force parameters was examined in order to observe the effect of postural alteration on muscle activity and balance control. The results showed that the change of squatting posture from FS to TT decreased the activity of the rectus femoris and tibialis anterior muscles. FS has been suspected as a main cause of musculoskeletal complaint during prolonged squatting. In contrast, as the heel was lifted, the extensor digitorum brevis muscle increased to 39% of maximum activation. On the other hand, sway analysis at TT showed balance instability regarding the large area occupation of the center of pressure displacement. The presence of a 15 degrees slope significantly reduced the muscular load. This simple study suggests that the inclusion of a sloping surface in daily activities that requires a squatting posture would be an effective means to reduce muscular load.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 02/2008; 27(1):11-7.
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    ABSTRACT: The effect of aging on muscular power development was investigated by determining the force-velocity relationship. The muscle cross-sectional area (CSA) was estimated by the thickness of the elbow flexors. The subjects were 19 elderly males aged 69.1+/-3.7 years old (G-70 group), 15 middle-aged males aged 50.9+/-3.5 years old (G-50), and 19 young males aged 21.2+/-1.3 years old (G-20). The G-70 group had the slowest shortening velocities under various load conditions, resulting in the lowest force-velocity relationship. The maximum values for force (Fmax), velocity (Vmax), power (Pmax), dynamic constants (a, b), and the a/Fmax ratio were determined using Hill's equation. The a/Fmax ratio determines the degree of concavity in the force-velocity curve. The a/Fmax ratio was greatest in G-70, followed by those in G-50 and G-20, while the maximum values for force (Fmax), velocity (Vmax), and power (Pmax) were significantly lower in G-70 than in the other groups. Fmax and Pmax per CSA were lowest in G-70, and Vmax per unit muscle length was also lowest in G-70 as compared to the other age groups. The ratio of G-70/G-20 was greatest in Pmax (69.6%), followed by Fmax (75.3%) and Vmax (83.4%). However, there were no significant differences in CSA among the 3 age groups. Our findings suggest that muscle force and shortening velocity may decline gradually in the process of aging attributed to declining muscle function rather than CSA.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 12/2007; 26(6):587-92.
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    ABSTRACT: 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.
    Journal of PHYSIOLOGICAL ANTHROPOLOGY 12/2007; 26(6):579-86.

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