Linda J. McCargar

Accuracy of subcutaneous fat measurement: Comparison of skinfold calipers, ultrasound, and computed tomography

OBJECTIVE The purpose of this study was to compare skinfold caliper and ultrasound measurement of subcutaneous body fat at three abdominal sites with computed tomography, which is considered to be the gold standard. DESIGN This was a cross-sectional study in which computed-tomography, ultrasound, and skinfold caliper measurements were made at three distinct abdominal sites. All body composition and anthropometric measurements were performed on each subject on one occasion. SUBJECTS Twenty-two subjects were recruited (13 men and 9 women). Mean ages (+/- standard deviation) were 43 +/- 4 years for the women and 51 +/- 18 years for the men. All subjects had been previously scheduled for an abdominal or pelvic computed-tomography scan at the Department of Radiology, St Pauls Hospital, Vancouver, British Columbia, Canada, and participated in the study on a volunteer basis. MAIN OUTCOME MEASURES A better agreement was found between the skinfold calipers and computed-tomography methods than between the ultrasound and computed-tomography method for the measurement of subcutaneous body fat. This was observed when the data were analyzed for both correlational agreement and for graphical interpretation. STATISTICAL ANALYSES PERFORMED The relationships among skinfold, ultrasound, and computed-tomography measurements were analyzed by determining Pearson correlation coefficients. A graphical method described by Bland and Altman was also used to assess agreement among the three methods. RESULTS Significant correlation coefficients were observed between skinfold calipers and computed tomography at all three abdominal sites (site 1, r = .60, P = .003; site 2, r = .70, P = .0001; site 3, r = .73, P = .0001). Ultrasound and computed-tomography methods only showed a significant correlation at site 3 (r = .54; P = .009). The graphical method revealed that the variation in the ultrasound measurements was much greater than that of the skinfold measurements when compared to computed-tomography values. APPLICATIONS/CONCLUSIONS The results of this study indicated that relative agreement in the measurement of subcutaneous body fat between skinfold and computed-tomography measurements was superior to that exhibited between ultrasound and computed-tomography measurements. This finding enhances the potential use of skinfold calipers in the clinical setting, particularly in view of the fact that measurement of subcutaneous body fat at different body sites is becoming increasingly important for the characterization of risk of certain disease states.

Effectiveness of two training methods to improve the quality of foodservice in small facilities for adult care

OBJECTIVE Community-based adult-care facilities (ACFs) with fewer than 25 beds provide homes for persons with disabilities who cannot live independently. The staff in these facilities are not required to have any formal foodservice training, yet they provide meals for the residents. The objective of this study was to evaluate the quality of foodservices before and after a foodservice training program. DESIGN Forty-six ACFs from six health-unit areas throughout the province of British Columbia were enrolled in the study, which involved a pretest-posttest design over a 5-month period. The health units were randomly assigned to one of three programs. INTERVENTION The ACFs received either a training workshop plus foodservice manual developed specifically for ACFs, the manual only, or no intervention. MAIN OUTCOME MEASURES Facilities were audited on performance in food purchasing, menu planning, food safety, and food storage. These areas were rated according to established minimum government regulations and other foodservice standards. Differences between the two audit scores (postintervention score minus preintervention score) were analyzed for each program section. Group comparisons were done using analysis of covariance procedures, with the initial score being the covariable. RESULTS No treatment effect was found on performance for food purchasing and food storage. Training via workshop plus manual resulted in a significant improvement in audit scores for menu planning and food safety compared with training via the manual alone. APPLICATION Dietitians should consider providing foodservice training workshops for similar types of facilities. The benefits of providing a manual alone are negligible.

Metabolic and anthropometric changes in female weight cyclers and controls over a 1-year period

OBJECTIVE Women who diet to lose weight often regain the weight over time, and the cycle repeats itself. The objective of this study was to identify a group of female weight cyclers and to match them with a control group who had never consciously tried to lose weight. For 1 year, weight patterns, eating habits, metabolic parameters, and body composition were assessed to determine whether there was a relationship between weight cycling and these variables. DESIGN Measurements were done at baseline and at 6 and 12 months. Changes in weight, diet, and exercise were monitored throughout the year. SETTING All testing was done at a university physiology laboratory. SUBJECTS/SAMPLES Nine weight cyclers with a notable history of dieting and food restriction were recruited. Subsequently, nine control subjects were selected and matched for age, height, weight, lean body mass, and exercise habits. MAIN OUTCOME MEASURE The observational study included measures of 3-day diet records, skinfold and girth, serum glucose, insulin and triiodothyronine, and resting energy expenditure. STATISTICAL ANALYSES PERFORMED The main variables were analyzed using a 2 x 3 (diet group x time) analysis of variance with repeated measures on the time factor. Comparison of the means was done by Tukey post hoc test. RESULTS A 7-point satisfaction scale indicated that the weight cyclers were dissatisfied with their weight compared with the noncyclers (P = .03). Otherwise, there were no differences between groups in dietary intakes or the physiologic variables. APPLICATIONS/CONCLUSIONS In the parameters measured, a history of weight cycling did not affect the metabolic profiles of the weight cyclers compared with the noncyclers.

Benefits of Exercise Training for Men With Insulin-Dependent Diabetes Mellitus

Twelve healthy men with IDDM participated in a 12-week walking/jogging exercise program. Pre- and postexercise assessment of dietary intakes, body composition, biochemical measures, and exercise performance indicators were completed. Subjects exercised either 3 or 5 days per week for 1 hour at 60% to 80% of estimated maximal heart rate. Dietary intakes showed a voluntary reduction in fat intake as a percent of total energy from 40% +/- 7% (mean +/- SD) to 37% +/- 8% (P = .053). No change occurred over time in body composition measures except for a significant reduction in the waist-to-hip ratio from 0.87 +/- 0.04 to 0.86 +/- 0.04 (P = .007). Fasting serum glucose and lipid levels did not change over time. Exercise capacity improved, as shown by an increased time to exhaustion on a treadmill run from 7.9 +/- 3.7 minutes to 9.7 +/- 3.8 minutes (P less than .001); and a lower heart rate at a constant work load--from 183 +/- 18 beats per minute preexercise to 175 +/- 20 beats per minute postexercise (P = .022). The study showed that healthy male subjects with IDDM can benefit from regular exercise with a redistribution of body fat and improved exercise capacity.

Effects of Exercise Modality on Metabolic Rate and Body Composition

This study was designed to investigate the effects of exercise as a strategy for weight management in overweight women. Specifically, the effects of exercise modality on resting energy expenditure (REE) and body composition [sum of skinfolds and fat-free mass (FFM)] were examined. Participants included 41 overweight, sedentary women aged 25–49 years who had a defined history of dieting. Experimental (n = 26) and control (n = 15) participants were recruited separately. Participants in the experimental group were randomly assigned to either an endurance-or a resistance-training exercise class. Exercise classes designed for a sedentary population were scheduled three times per week for a duration of 3 months. Results indicated that exercise modality had no effect on REE. Exercise, regardless of modality, had a significant effect on body composition (p = 0.0001) as shown by a significant decrease in the sum of skinfolds for the two exercise groups relative to the control group (p<0.0001). No differences in fat-free mass were observed between groups. Regardless of modality, exercise also resulted in an increased estimated maximum oxygen uptake (VO2 max), based on a 1-mile walking test (p = 0.012). The pattern of weight change of the groups was different (p = 0.029) over the 3-month period. Whereas the exercise groups maintained their weight, the control group gained weight (∼2.5 kg). Thus, although exercise modality had no effect, the benefits of exercise per se, such as decreased body fat, increased fitness level, and weight maintenance, were observed in this population.

Weight Cycling in Competitive Judokas

It has been suggested that weight cycling may lead to physiological adaptations that cause resistance to future weight loss. Athletes who compete in judo represent an athletic model of weight cycling. Two matched groups of male judokas were observed: weight cyclers (n = 9) and noncyclers (n = 9). Resting energy expenditure, skinfold and girth measures, serum glucose, insulin and triiodothyronine levels, and 3-day dietary intakes were determined three times within a 1-year period. The weight cyclers lost 4.1 ± 1.5 kg (mean ± SD) an average of 4.2 ± 2.7 times per season and quickly regained the weight between competitions. There was no significant difference in metabolic or biochemical parameters between groups during any of the three test sessions. This study suggests that there is no prolonged effect of weight cycling in this athletic population.

Managing Activity in Patients Who Have Diabetes. Practical Ways to Incorporate Exercise into Lifestyle.

In brief Control of both type I and type II diabetes involves the appropriate balance of exercise, diet, and medication. Regular, long-term exercise has many benefits for people with diabetes. Physicians can educate patients about ways to regulate and monitor blood glucose before, during, and after a workout or competition. Physicians also need to discuss the warning signs of hypoglycemia, hyperglycemia, ketoacidosis, and dehydration and how to prevent the conditions. In addition, patients who have type I diabetes need to know the effects of exercise on insulin requirements. Nutrition needs will vary for each patient, type of activity, and other factors, but food intake can be readily adjusted in conjunction with blood glucose monitoring.