Beverly J. Warren

Physical activity and immune function in elderly women.

The relationship between cardiorespiratory exercise, immune function, and upper respiratory tract infection (URTI) was studied in elderly women utilizing a randomized controlled experimental design with a follow-up of 12 wk. Thirty-two sedentary, elderly Caucasian women, 67-85 yr of age, who met specific selection criteria, were randomized to either a walking or calisthenic group; 30 completed the study. Twelve highly conditioned elderly women, 65-84 yr of age, who were active in endurance competitions, were recruited at baseline for cross-sectional comparisons. Intervention groups exercised 30-40 min, 5 d.wk-1, for 12 wk, with the walking group training at 60% heart rate reserve and the calisthenic group engaging in mild range-of-motion and flexibility movements that kept their heart rates close to resting levels. At baseline, the highly conditioned subjects exhibited superior NK (119 +/- 13 vs 77 +/- 8 lytic units, P < 0.01) and T (33.3 +/- 4.9 vs 21.4 +/- 2.1 cpm x 10(-3) using PHA, P < 0.05) cell function, despite no differences in circulating levels of lymphocyte subpopulations. Twelve weeks of moderate cardiorespiratory exercise improved the VO2max of the sedentary subjects 12.6%, but did not result in any improvement in NK cell activity or T cell function. Incidence of URTI was lowest in the highly conditioned group and highest in the calisthenic control group during the 12-wk study, with the walkers in an intermediate position (chi-square = 6.36, P = 0.042). In conclusion, the highly conditioned elderly women in this study had superior NK and T cell function when compared with their sedentary counterparts.(ABSTRACT TRUNCATED AT 250 WORDS)

Immune function in marathon runners versus sedentary controls

Marathon runners (N = 22) who had completed at least seven marathons (X +/- SEM = 23.6 +/- 5.7) and had been training for marathon race events for at least 4 yr (12.3 +/- 1.3) were compared with sedentary controls (N = 18). Although the two groups were of similar age (38.7 +/- 1.5 and 43.9 +/- 2.2 yr, respectively) and height, the marathon runners were significantly leaner and possessed a VO2max 60% higher than that of the controls. Neutrophil counts tended to be lower in the group of marathoners, while other leukocyte and lymphocyte subsets were similar to controls. Mitogen-induced lymphocyte proliferation did not differ between groups. Natural killer cell cytotoxic activity (NKCA) was significantly higher in the marathoners versus controls (373 +/- 38 vs 237 +/- 41 total lytic units, respectively, a 57% difference, P = 0.02). For all subjects combined (N = 40) and within the group of marathon runners (N = 22), percent body fat was negatively correlated with NKCA (r = -0.48, P = 0.002; r = -0.49, P = 0.019, respectively), and age was negatively correlated with Con A-induced lymphocyte proliferation (r = -0.41, P = 0.009; r = -0.53, P = 0.011, respectively). These data indicate that NKCA but not mitogen-induced lymphocyte proliferation is higher in marathon runners relative to sedentary controls.

Disordered eating patterns in competitive female athletes

In an effort to identify risk for disordered eating patterns in competitive female athletes, the present study compared a sample of NCAA Division I female athletes (n = 74) to a college female nonathlete control group (n = 52). Measures included the Eating Disorders Inventory (EDI) (Garner, Olmsted, & Polivy, 1983), the Eating Attitudes Test (EAT) (Garner & Garfinkel, 1979), and body mass. Findings indicated that none of these highly trained athletes had scores indicative of the constellation of disturbances in eating patterns and personality attributes seen in anorexia nervosa or bulimia. Rather, results suggested that the typical college female athlete falls into the normal range with regard to body mass and eating patterns. The competitive female cross-country runner actually may be at slightly less risk for body dissatisfaction than her nonathlete counterpart, whereas the gymnast may be at somewhat greater risk for weight preoccupation.

Physical Activity and Serum Lipids and Lipoproteins in Elderly Women

Objective: The relationship between cardiorespiratory exercise and serum lipid and lipoprotein levels was studied in elderly women.

Exercise training and nutrient intake in elderly women

This study examined the relationship between moderate exercise training (five 30- to 40-minute sessions per week for 12 weeks at 60% of heart rate reserve) and changes in nutrient intake in a group of 30 sedentary elderly women aged 67 to 85 years. Subjects were placed randomly into two groups (those who walked and those who did calisthenics) and were followed for 12 weeks. Measurements were done at three times (baseline, 5 weeks, and 12 weeks). Dietary intake was based on 7-day food records. The 12-week walking program resulted in a significant (12.6%) improvement in maximum oxygen consumption (VO2max) but no change in body weight or skinfold thicknesses compared with the calisthenics program. Despite the improvement in cardiorespiratory fitness, no significant group x time interaction effects were observed for most of the nutrient intake variables tested. To test the effects of high levels of physical activity on nutrient intake, cross-sectional comparisons were made at baseline between highly conditioned and sedentary elderly women. The highly conditioned elderly women had higher energy and nutrient intakes, especially when expressed on a weight-adjusted basis. However, no differences in measures of dietary quality were found. Dietitians should not expect spontaneous improvement in either the quantity or quality of nutrient intake by elderly women who adopt a moderate exercise program. Although nutrient intake was greater in highly conditioned elderly women, their level of fitness and physical activity may be beyond the reach of many elderly women.

Glucose Uptake After Resistance Training of Different Intensities but of Equal Work Volume

Luebbers, PE, Potteiger, JA, Warren, BJ, Clore, JN, Jennings, C, and Bond, DS. Glucose uptake after resistance training of different intensities but of equal work volume. J Strength Cond Res 22: 1094-1100, 2008-High-intensity (HI) resistance exercise augments postexercise glucose uptake to a greater degree than low-intensity (LO) resistance exercise; however, few studies have equated the work volumes between intensity levels. The purpose of this study was to compare the effect of acute HI and LO resistance exercise of equal work volume on glucose uptake in resistant-trained men. Fifteen healthy male (22.9 ± 3.8 years old), resistance-trained (6.7 ± 3.9 years) subjects completed three treatment sessions: CON (no-exercise control), HI (3 × 8, 85% 10-RM), and LO (3 × 15, 45% 10-RM). HI and LO sessions consisted of eight exercises. Glucose uptake was measured the following morning by using the hyperinsulinemic euglycemic clamp technique. Glucose disposal was measured by analyzing the glucose infusion rate during the final 30 minutes of steady-state blood glucose concentrations. Insulin sensitivity was calculated by dividing the glucose infusion rate by the average insulin infusion. Results indicate that fasting blood glucose levels were not significantly different among treatment sessions (CON = 80.5 ± 5.3 versus HI = 77.0 ± 4.9 versus LO = 77.1 ± 6.0 mg·dL−1). Glucose uptake was not significantly different among treatment sessions (CON = 11.3 ± 3.0 versus HI = 11.7 ± 2.7 versus LO = 11.4 ± 2.8 mg·kg FFM−1·min−1). Insulin sensitivity did not change among treatment sessions (CON = 0.26 ± 0.09 versus HI = 0.28 ± 0.07 versus LO = 0.27 ± 0.06 (mg·kg FFM−1·min−1)/(uU·mL−1)). The data indicate that the resistance training sessions did not modify acute insulin sensitivity. This may have been because of the high levels of fitness of the subjects, which allowed for the cellular adaptations for enhanced insulin sensitivity and glucose uptake that are unaffected by this volume of acute exercise.