B-mode ultrasound was used to measure fat and muscle thicknesses on 30 subjects (17 men, 13 women, age = 20-37 yr) at 14 sites (triceps, biceps, forearm, chest [males only], subscapular, axilla, abdomen, suprailium, lumbar, quadriceps, suprapatellar, hamstrings, medial calf, and posterior calf) on two different days. Quadruplicate photographic images (trials) were printed from a single measurement at each site on each day. Two investigators each measured two of the images from each site. Each thickness was measured to the nearest 0.05 mm with a vernier caliper. Generalizability theory was used to determine the relative contribution of subjects, investigators, days, and trials to the total measurement variability. Subjects accounted for 84-96% of the variance in the muscle measurements and for 79-97% of the variance in the fat measurements. A subjects-by-day interaction accounted for 2-13% of the variance in muscle measurements and 2-12% of the variance in fat measurements. The contribution by investigators and trials to the variance was less than 1%. Generalizability coefficients (G) exceeding 0.92 were obtained for all sites for muscle measurements, while G for fat measurements exceeded 0.90 for all but the axilla site (G = 0.88). These results indicate that B-mode ultrasound is a highly reliable method for the measurement of both fat and muscle thicknesses in young males and females. © 1992 Wiley-Liss, Inc.

The purpose of this study was to investigate the effects of 6 months of walking training on muscle strength, muscle thickness and tendon stiffness on various parts of the lower limbs in the elderly. Subjects were assigned to training (n=35) and control (n=10) groups. Maximal isometric torque (MVC) and muscle thickness for knee extensors (KE), knee flexors (KF), dorsi flexors (DF) and plantar flexors (PF) were measured. Tendon stiffness for KE and PF was measured using ultrasonography while subjects performed isometric contraction. No significant changes occurred in any measured variables in the control group. In the training group, muscle thickness increased significantly for KF and DF, but not for PF. For KE, significant increases of muscle thickness at the proximal and medial sides were observed, although mean relative increase of the eight measured sites for KE was not significant. MVC increased significantly for KF, DF, and PF, but not for KE. In addition, tendon stiffness for KE and PF did not change after training. These results indicated that walking training brought about increments of muscle thickness and strength in most of the lower limbs in the elderly, but it did not result in any changes in tendon stiffness.

Betaine is an important human nutrient obtained from various foods. In the present study, we assessed the anti-inflammatory effect of betaine on nuclear factor-jB (NF-jB) during aging. Sprague-Dawley (SD) rats, ages 7 and 21 months, were used in this study. The older rats were fed betaine. To elucidate the effect of betaine on oxidative stress-induced NF-jB and its signaling pathway at molecular levels, YPEN-1 cells were used. Results showed that betaine suppressed NF-jB and its related gene expressions of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), vascular cell adhesion molecule-1 (VCAM-1), and intracellular cell adhesion molecule-1 (ICAM-1) in aged kidney. Furthermore, betaine attenuated oxidative stress-induced NF-jB via nuclear factor-inducing kinase/IjB kinase (NIK/IKK) and mitogen-activated protein kinases (MAPKs) in the YPEN-1 cells. On the basis of these results, we concluded that betaine suppressed the age-related NF-jB activities associated with upregulated NIK/IKK and MAPKs that were induced by oxidative stress. Thus, betaine might be useful as a preventive agent against the activation of NF-jB induced during inflammation and aging.

Abstract. The present study was designed to investigate the influences of aerobic training on the body composition, aerobic power and food intake of sedentary young females in relation to the initial levels of these variables. Thirty one untrained college females (age=19.8 ± 0.2 yr, stature=154.4 ± 0.8 cm, body mass=53.3 ± 1.2 kg, mean ± SEM) participated in an exercise regimen consisting • of 40% of maximum oxygen uptake (VO2max) for 30 minutes per day on a bicycle ergometer 5 times a week in a training period of 12 weeks. Food consumption was ad libitum but the content of daily food intake was recorded accurately throughout the whole training period and analyzed weekly. The average body mass index (BMI) and fat mass relative to body mass (%FM), estimated from the data of skinfold thickness, decreased significantly after the 12 wk training. There were significant negative correlations between the relative changes (%∆s) and initial levels of both body mass (r= 0.447, p<0.05) and fat mass (r= 0.638, p<0.05), but the corresponding correlation for lean body mass (LBM) was not significant (r=0.186, p>0.05). While the energy intake during the training period did not differ significantly from that during the control period on the average, the %∆ value in energy intake between the two periods was negatively correlated to the energy intake during the control period (r= 0.604, p<0.05). In addition, there were low but significant negative correlations between both the initial levels of BMI and %FM and %∆ in energy intake; r= 0.413 (p<0.05) for BMI and r= 0.393 (p<0.05) for %FM. However, no significant correlations were found between %∆ in energy intake and those in body composition variables (r=0.116 to 0.237, p>0.05).•

No abstract