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Biomedical subjects

G B Spurr

Publications and source records attributed to G B Spurr.

At least 37 records · Page 2Linked to original sources
PubMed1988

Body composition of patients with spinal cord injury.

Body composition of 10 control subjects and 37 spinal cord injured (SCI) patients was measured by dilution of 3H2O and Na2 35SO4. SCI patients were classified into four groups by ascending level of lesion, low and high paraplegics and low and high quadriplegics. The studies show diminishing total body water, intracellular water, lean body mass and body cell mass and increasing fat mass with higher spinal lesions. No differences in body weight or extracellular water were observed so that the ratio of extracellular water/total body water was increased as the level of injury increased.

Adult↗
PubMed1988

Patterns of daily energy expenditure in normal and marginally undernourished school-aged Colombian children.

Using minute-by-minute heart rate recording, the pattern of energy expenditure (EE), total daily energy expenditure (TDEE) and energy expenditure in activity (EAC) were measured in 132 boys and 110 girls 6-8, 10-12 and 14-16 years of age during ordinary school days. The children were living under economically deprived conditions in Colombia; 70 boys and 59 girls were classified as having marginal malnutrition of sufficient degree to retard growth and sexual maturation. EE, TDEE and EAC increased with age, were in general less in undernourished than control subjects and less in girls than in boys. The age and nutritional group effects were ascribable to differences in lean body mass (LBM). However, the reduced activity in girls was greater than could be accounted for by differences in LBM and are probably the result of cultural pressures. Thus, at the levels of normal activity encountered during school days, the reduced energy expenditure found in undernourished children can be accounted for by differences in body size.

Adolescent↗
PubMed1988

Influence of dietary intervention on artificially increased activity in marginally undernourished Colombian boys.

Studies of the pattern of daily energy expenditure (EE), total daily energy expenditure (TDEE) and energy expended in activity (EAC) have been carried out in 14 nutritionally normal and 19 marginally malnourished, free-living boys 10-12 years of age using the minute-by-minute heart rate recording technique. Measurements were made during an ordinary school day and again about 6 months later under conditions of a summer day-camp where the activity levels were artificially increased by encouragement to participate in supervised sports activities and play. The morning and afternoon activities were separated by a dietary intervention in the form of a hot meal providing approximately 3.2 MJ (760 kcal). In the morning sessions of the day-camp the undernourished boys did not keep up with the control group by increasing their EE. However, for about 2 h following the noon meal, they did increase EE to levels comparable to the control group but again reduced their EE later in the afternoon and earlier than the control subjects. The data show an inability of undernourished boys to increase their activity which is positively affected for a short period by dietary intervention.

Child↗
PubMed1987

Marginal malnutrition in school-aged Colombian girls: dietary intervention and daily energy expenditure.

Total daily energy expenditure (TDEE) and energy expended in activity (EAc) were estimated in 24 control (nutritionally normal) and 20 marginally undernourished girls, 8-11 years of age, before and after a dietary intervention which supplied an average of approximately 600 kcal/d only to the undernourished subjects. In the latter, the velocity of weight gain was significantly increased after dietary supplementation as were skinfold thickness and mid-arm circumference. EAc was not diminished in the undernourished subjects nor did it increase following dietary supplementation. It is suggested that in school-aged children, peer pressure to keep up with activities in school and play may attenuate the reduced activity sometimes seen in preschool and adult subjects as a response to restricted energy intake. Instead, at marginal levels of malnutrition, reduced growth in the school-aged group may be the first level of response with reduced physical activity seen only at more severe levels of nutritional deprivation.

Basal Metabolism↗
PubMed1986

Marginal malnutrition in school-aged Colombian boys: metabolic rate and estimated daily energy expenditure.

Total daily energy expenditure (TDEE) and energy expenditure in activity (EAc) were estimated in 114 free-ranging, nutritionally normal, and undernourished boys 6-16 yr of age by measuring basal and resting metabolic rates, average daily heart rate while awake, and oxygen consumption and heart rate during exercise on a treadmill. Mean daily heart rates were in the range of exercising heart rates and gave reasonable estimates of TDEE and EAc. TDEE increased with age (p less than 0.001) and was reduced in undernourished boys (p = 0.011). Results indicate that nutritional group differences in TDEE were due to differences in body size. EAc increased with age but did not show significant differences between nutritional groups, indicating that in the marginal malnutrition of school-aged children, reduced growth and associated economy of energy expenditure in locomotion is sufficient physiological adaptation. Peer pressure in school and play activities may interfere with the protective mechanism of reduced activity.

Adolescent↗
PubMed1986

Marginal malnutrition in school-aged Colombian boys: body size and energy costs of walking and light load carrying.

The energy expenditure of 93 Colombian boys 6-16 years of age and 10 adult American males was measured while walking on a treadmill at 3 mph and 0, 4, 8 and 12 per cent grades without and with backpack loads of 3 (6-8 year), 6 (10-12 year) and 9 kg (14-16 year and adults). The boys were also divided into nutritionally normal and marginally malnourished, based on their weight-for-age and weight-for-height. The primary dependency of energy expenditure on body weight or body weight plus load was not affected by nutritional status, and the results of both adults and control and undernourished children fell on the same straight line at a given treadmill grade, indicating that the undernourished subjects would expend the same energy as nutritionally normal boys and adult subjects for a given load carried. The undernourished boys worked at a higher percentage VO2 max than control subjects when load carrying.

Adolescent↗
PubMed1986

Strength and range of motion in the ankle in two age groups of men and women.

Strength and range of motion of the ankle were measured in 20 normal men and 20 normal women divided equally into two age groups (25-35 and 50-60 years). Total range of dorsiflexion/plantar flexion averaged 75 degrees and the total range of inversion/eversion averaged 28 degrees. Few significant differences in range of motion were found between age groups, between men and women, or between dominant and nondominant limbs. Mean torque values for the men were greater than those for the women for all four muscle groups tested (plantar flexors, dorsiflexors, invertors and evertors). Strength of the women ranged from 62 to 70 percent of that of the men, depending upon muscle group. A multiple regression analysis showed that after the variability in muscle strength due to height and lean body weight had been taken into account, the additional variance accounted for by gender was very small. Differences in torque between age groups were not statistically significant. Differences in strength between dominant and nondominant limbs were significant only for the plantar flexors and dorsiflexors of the men.

Adult↗
PubMed1985

Treadmill vs. floor walking: kinematics, electromyogram, and heart rate.

To identify the degree of difference between treadmill and floor walking, kinematic, electromyographic (EMG), and heart rate measurements were recorded in seven normal female subjects during walking at three speeds on the treadmill and on the floor. During treadmill walking, subjects tended to use a faster cadence and shorter stride length than during floor walking. In addition the displacements of the head, hip, and ankle in the sagittal plane showed statistically significant differences between floor and treadmill walking. Average EMG activity was usually greater on the treadmill than on the floor; however, this difference was only significant for the quadriceps. Heart rate was significantly higher during fast treadmill walking than floor walking. In general, treadmill walking was not found to differ markedly from floor walking in kinematic measurements or EMG patterns.

Adult↗
PubMed1985

Daily energy expenditure and basal metabolic rates of patients with spinal cord injury.

Basal metabolic rate (BMR) and daily energy expenditure were measured in 48 men with complete traumatic transections of the spinal cord. Subjects were classified according to their residual motor function as high or low quadriplegic (HQ, LQ) or as high or low paraplegic (HP, LP). Measured BMR was lower than predicted BMR in almost all of the subjects and was significantly lower in the HQ group than in the other groups. High quadriplegics also expended significantly less energy while awake and over a 24-hour period than did the other groups. Measurements of BMR and total energy expenditure were significantly correlated with the level of lesion. The data provide a basis for establishing guidelines on the average energy needs of patients with spinal cord injury.

Adult↗
PubMed1984

Marginal malnutrition in school-aged Colombian boys: efficiency of treadmill walking in submaximal exercise.

Measurements of oxygen consumption (VO2) were made during submaximal treadmill exercise (3.5 mph) in 658 boys 6 to 16 yr of age classified as nutritionally normal, low weight for age, and low weight for height. Gross efficiency (at 15% grade) increased with age and was significantly lower in low weight for age and height boys than in normal children but delta efficiency showed no statistically significant differences between nutritional groups. It is concluded that marginal malnutrition has no effect on the efficiency of submaximal work during treadmill walking.

Adolescent↗
PubMed1984

Marginal malnutrition in school-aged Colombian boys: body composition and maximal O2 consumption.

Do changes in body composition account for the changes in O2 consumption during maximal exercise (VO2max) in nutritionally deprived boys? School age urban and rural boys with no deficits (N) or with significant deficits (W-H) in weight for age and for height were studied. Percentage lean body mass was higher in W-H than in N boys. By contrast percentage intracellular water, the creatinine excretion coefficient and percentage arm muscle mass were not higher in W-H boys. Thus nutritional compromise decreased more the cellular than the support tissues of the body. VO2max per unit body weight was higher in W-H than in N boys. In the rural group, this was accounted for by the higher percentage lean body mass in W-H boys. In the urban group, VO2max/lean body mass was also higher in most W-H boys. Thus W-H urban boys had higher levels of aerobic training than N urban boys, reflecting perhaps a relative increase in daily physical activity as the same tasks have to be performed with less muscle by W-H boys.

Adolescent↗
PubMed1983

Marginal malnutrition in school-aged Colombian boys: anthropometry and maturation.

Colombian reference data for weight and height were used to classify 1108 boys 6 to 16 yr old as nutritionally normal, low weight for age, and low weight for height. The normal group in upper socioeconomic urban and normal, low weight for age, low weight for height groups in lower socioeconomic urban and rural populations were studied. The achieved growth, growth velocities, skinfolds, mid-arm and head circumferences, and sexual maturation were all depressed in the nutritionally deprived groups indicating marginal malnutrition. Since normal boys exist in low socioeconomic and rural populations, normative data for economically advantaged children (national standards), on the average, may serve as desirable goals for low socioeconomic and rural populations. Different cutoff points for achieved growth might be established for marginal malnutrition using national or international reference populations. These ought to be age-related because of accumulated effect of slowed growth with age. Head circumference of school-aged children may proved a useful anthropometric tool in deciding early nutritional history.

Adolescent↗
PubMed1983

Marginal malnutrition in school-aged Colombian boys: functional consequences in maximum exercise.

The maximum treadmill oxygen consumption was measured in 1013 boys, 6 to 16 yr of age classified as nutritionally normal, low weight for age and low weight for height in upper socioeconomic urban and lower socioeconomic urban and rural groups. The marginally malnourished children (low weight for age and height) in both lower socioeconomic urban and rural groups had significantly depressed maximum treadmill oxygen consumption (85%) compared to normal boys, associated with smaller body weights. It is suggested that the reduced body size and maximum treadmill oxygen consumption resulting from marginal malnutrition during growth will have a detrimental effect on work capacity and productivity of these children when they become engaged in heavy physical work as adults. There was no statistically significant correlation between blood Hb concentration (approximately 10 to 15 g x dl-1) and aerobic capacity.

Adolescent↗
PubMed1981

Comparisons of body fat estimated from total body water and skinfold thicknesses of undernourished men.

In 49 chronically undernourished adult males, classified as having mild, intermediate, or severe nutritional compromise, comparisons were made of body fat calculated from total body water with values obtained from triceps and scapular skinfolds. These same comparisons were followed in 19 of the severely undernourished subjects during a 2 1/2-month period of dietary repletion. Results indicate that the correlations between fat estimates obtained from body water and skinfolds are good (r greater than 0.8) in mildly undernourished subjects, but that they are progressively reduced as the nutritional compromise becomes more severe until statistical significance disappears. Dietary repletion of 2 1/2-month duration did not restore a statistically significant relationship between fat and triceps and scapular skinfolds. These data imply that the triceps and scapular skinfolds do not adequately represent body fat in chronically undernourished adult males and that new empirical equations are required which take into account nutritional status and possible shifts in fat deposit sites in chronic undernutrition.

Adult↗
PubMed1980

Aerobic work capacity and endurance during nutritional repletion of severely undernourished men.

Oxygen consumption in maximal exercise (VO2max) was found to increase during nutritional rehabilitation of severely undernourished, sedentary adult males only when dietary protein was increased from 27 to 100 g/day. Adequate caloric intake, maintained for 45 days before the increase in protein content of the diet, had no effect on VO2max. The VO2max values were found to correlate best with the creatinine excretion rates (an index of the muscle cell mass) at the different stages of repletion. The average increment in VO2max/muscle cell mass ratio, although significant, was of a small magnitude (+15%). The VO2max/muscle cell mass ratio correlated only with the blood and plasma volumes at the different stages of repletion. After 2.5 months of protein repletion the VO2max values were still lower than those in mildly undernourished or normal Colombian adult males. Maximal endurance time at 80% aerobic load decreased significantly from an average of 113 min at the beginning of hospitalization to 42 min at the end of the period of protein repletion. This could be the result of replacing carbohydrate calories with protein in the diet, producing depletion of muscle glycogen stores, and/or to "detraining" effects associated with sedentary hospital life.

Adult↗
PubMed1979

Functional assessment of nutritional status: heart rate response to submaximal work.

The heart rate response to submaximal treadmill work been calculated using the heart rates and oxygen intakes obtained from normally nourished and undernourished adult male subjects during a maximal oxygen consumption test. Increased severity of malnutrition was associated with an increased heart rate response to the same submaximal work loads. The response was observed to decrease during a period of high protein dietary repletion of the most severely malnourished subjects. The data suggest the possibility of developing a submaximal work test for use in the field to provide physiological data to supplement anthropometric and biochemical information used to assess the nutritional status of populations.

Adolescent↗