Mariane M. Fahlman

Effects of ginseng on secretory IgA, performance, and recovery from interval exercise

PURPOSE This study examined the efficacy of ginseng to modulate secretory immunoglobulin A (SIgA), exercise performance, and recovery from repeated bouts of strenuous physical exertion. METHODS Using a double-blind, placebo-controlled, randomized design, 38 active healthy adults supplemented their diets with a standardized ginseng concentrate (400 mg.d-1 of G115; equivalent to 2 g of Panax ginseng C.A. Meyer root material) or placebo (lactose) for 8 wk. Before and after the intervention, each subject performed three consecutive 30-s Wingate tests interspersed with 3-min recovery periods under controlled laboratory conditions. SIgA secretion rate (S-SIgA) and the relation of SIgA to total protein were calculated from measures of saliva flow rate (SFR), and absolute SIgA and salivary protein concentrations in timed, whole unstimulated saliva samples collected before and after exercise testing. Peak and mean mechanical power output (W.kg-1) was measured with an infrared-beam optical-sensor array, and exercise recovery heart rate (HRR) was determined electrocardiographically. RESULTS Twenty-seven subjects (12 placebo, 15 ginseng) completed the study. Compared with rest, S-SIgA, SIgA:protein ratio, and SFR were lower after exercise at baseline (P < 0.05). Similarly, both peak and mean mechanical power output declined (P < 0.01) across consecutive Wingate tests. Postintervention minus preintervention change scores for salivary parameters, exercise performance, and HRR were similar between ginseng- and placebo-treated groups (P > 0.05). CONCLUSION These findings do not support the hypothesis that ginseng may affect mucosal immunity as indicated by changes in secretory IgA at rest and after an exercise induced state of homeostatic disturbance. Supplementation with ginseng fails to improve physical performance and heart rate recovery of individuals undergoing repeated bouts of exhausting exercise.

Racial and Socioeconomic Disparities in Nutrition Behaviors: Targeted Interventions Needed

OBJECTIVE To compare dietary knowledge, behaviors and self-efficacy of black middle school students of low socioeconomic status with their white counterparts of higher socioeconomic status. DESIGN Cross-sectional, school-based survey. SETTING Large metropolitan area in the United States. PARTICIPANTS Middle school students (1,208 of low socioeconomic and 978 of higher socioeconomic status). MAIN OUTCOME MEASURES Dietary behaviors, dietary knowledge, and dietary self-efficacy were assessed by questionnaire. ANALYSIS Differences between black students of low socioeconomic status and white students of higher socioeconomic status in the above variables. RESULTS Black students of low socioeconomic status scored significantly lower than did white students of higher socioeconomic status on several of the variables. They were more likely to consume empty calorie food, meat, and fried food and less likely to eat fruit, vegetables, dairy products, and grains; they were less knowledgeable about dietary variables; and they had significantly lower self-efficacy regarding their ability to change dietary habits. CONCLUSIONS AND IMPLICATIONS The results of this study suggest that black students of low socioeconomic status should be targeted for early intervention related to dietary behaviors. This age group is amenable to change, and interventions designed specifically for them may result in lifetime reductions in risk of morbidity and mortality.

Effects of Resistance Training on Functional Ability in Elderly Individuals

Purpose. Determine the effects of 16 weeks of strength training on measures of functional ability in elderly who are functionally limited. Design. Quasi-experimental trial in which elderly volunteers were assigned to either an exercise group or a control group. Participants. Eighty-seven participants (65–93 years) living independently but with some functional limitations. Intervention. Thirteen different strength training exercises using Thera-Band resistive bands (Hygenic Corporation, Akron, Ohio). The program was 16 weeks in duration, and the frequency was three times per week. Participants exercised in a group setting one time per week and were given a home exercise book to follow for two additional sessions per week. Measures. Functional ability was operationalized to include a variety of measures related to functional ability that impact activities of daily living, morbidity, and mortality in the elderly, including upper- and lower-body strength and gait. Analysis. Intervention effects were analyzed using a 2 (groups: exercise group vs. control group) X 3 (time: baseline vs. mid vs. post) analysis of variance. Results. The exercise group demonstrated significant improvements in upper-body strength as measured by biceps curl (F[2,140] = 39.870; p < .05) and lower-body strength as measured by chair sit-to-stand (F[2,124] = 25.887; p < .05). Gait velocity (F[2,140] = 37.317; p < .05) and step length (F[2,140] = 4.182; p < .05) both increased for the exercise group at week 9, but this increase disappeared by week 17. Compared with minimal changes in the control group, the exercise group demonstrated significant improvements in upper-body strength as measured by biceps curl and lower-body strength as measured by chair sit-to-stand. Conclusion. Some measures of function ability were improved after a 16-week structured exercise program for functionally limited elderly. Because functional ability has been inversely correlated with short-term morbidity and the need for assisted living among older adults, providing opportunities to exercise is crucial to future functioning and independence of the elderly population. (Am J Health Promot 2011;25[4]:237–243.)

Exercise and Functional Tasks Among Adults Who Are Functionally Limited

This study compared the efficacy of 16 weeks of either resistance training, aerobic walking, or combined resistance training and aerobic walking on the performance of functional tasks among adults age 65 years and older with limited functional ability. One hundred thirty-one older adult individuals were randomized into four groups: resistance training, aerobic walking, combined resistance and aerobic walking groups, or a nonexercise control group. Each of the exercise groups documented 70% compliance with their respective exercise intervention, which included three weekly exercise sessions. At baseline, and 8 and 16 weeks following baseline, all participants completed six assessments of their functional ability. Analysis of covariance indicated that all three exercise intervention groups significantly improved measures of functional ability, with the resistance group demonstrating the most consistent gains over the six measures. These findings indicate that older adults who are functionally limited can improve their functional ability through a variety of types of exercise.

Effects of hormone replacement therapy on selected indices of immune function in postmenopausal women

The purpose of this study was to examine the effects of long-term hormone replacement therapy (HRT) on selected indices of resting immune function in postmenopausal women. Postmenopausal women aged 54–66 were divided into two groups, those taking HRT (n = 17) and controls (n = 19). Blood samples were obtained and analyzed for mononuclear cell numbers, lymphocyte proliferation (LP) and natural cell-mediated cytotoxicity (NCMC). There were no significant differences between groups for mononuclear cell numbers. LP was significantly higher for HRT, while NCMC was significantly lower for HRT. HRT is currently being prescribed to postmenopausal women for prevention of a variety of medical conditions including osteoporosis, cardiovascular disease, stroke, and Alzheimer’s disease yet HRT is often associated with altered immune parameters. In this study, women taking HRT had increased lymphocyte blastogenesis and decreased NCMC compared to controls.

Effects of Exercise on S-IGA and URS in Postmenopausal Women

32 postmenopausal women were randomized to a 16-week home-based walking program or control group. Before and after the intervention, each subject completed a graded maximal treadmill test to establish VO(2)max and resting saliva was collected to determine levels of salivary immunoglobulin A. The 16-week walking program resulted in an increase in VO(2)max (+10.4%; p<0.01). Repeated measures ANOVA revealed a marked increase in the resting secretion rate of salivary immunoglobulin A (+37.4%; p<0.05) in the exercise group following training. Independent of study group, both before and after the intervention, the secretion rate of salivary immunoglobulin A ( - 32.3%) and saliva flow rate (- 29.3%) were reduced following acute maximal exercise (p<0.05). Weekly upper respiratory symptomatology logs revealed that the number of incidences of upper respiratory symptoms throughout the intervention period were the same and the duration per incidence (control: 5.3±1.5 days; exercise: 6.3±2.2 days) were similar between study groups. These findings in postmenopausal women support that the secretion rate of salivary immunoglobulin A and saliva flow rate are reduced immediately following maximal exercise. Moreover, a 16-week moderate intense walking program can increase the secretion of salivary immunoglobulin A without affecting upper respiratory symptomatology.

Hydration status of community-dwelling seniors.

Background and aims: Dehydration is the most common fluid or electrolyte disorder among older persons. This study was designed to examine the hydration status of community-dwelling seniors. Methods: Blood and urine samples were collected from 67 independently living volunteers (65–93 yrs) who had functional limitations but no condition that contraindicated 10 min of moderate exercise. Forty-six subjects who were not diabetic, had fasted for 12 hours, and had blood glucose levels ≤115 mg/dL were thus included. Urine and serum samples were analyzed for osmolality (mosm/kg), Na+ (mmol/L) and K+ (mmol/L). Whole blood was analyzed for hemoglobin (Hb, g/dL) and hematocrit (Hct, %) and urine for specific gravity (USG). Means and standard deviations for the current data were compared with normal values. Results: All values were within normal ranges except urine osmolality. Conclusions: While changes associated with aging may predispose an individual to dehydration, functionally limited, independently living older individuals demonstrate normal hydration status following a 12-hr fast. This suggests that dehydration is not solely a function of the aging process, but may be more related to concomitant medical conditions or dependent living.

Resiliency, Control, Enjoyment and Physical Activity in African American High School Students

Resiliency, Control, Enjoyment and Physical Activity in African American High School Students The purpose of this study was to explain physical activity (PA) using Block and Blocks (2006a) ego-resiliency and ego-control theory along with measures of self-control and PA enjoyment. One-hundred and seventy-seven African American high school students from a large Midwest inner city participated. In general, cluster analyses provided support for the importance of ego-resiliency and PA enjoyment as there were strongly affiliated with differential amounts of PA. Ego-control and self-control were also important in cluster formation but related to PA in somewhat unexpected ways.

Assessing the Eating Behaviors of Low-income, Urban Adolescents

Abstract Background: There is a need for instruments that can accurately determine the effectiveness of nutrition interventions targeting low-income, inner-city adolescents. Purpose: To examine the development of a valid and reliable eating behavior scale (EBS) for use in school-based nutrition interventions in urban, inner-city communities dominated by high poverty, food insecurity and academic underperformance with primarily minority residents. Methods: The research was conducted with 387 minority adolescents in an inner-city urban school. Reliability was determined by administering the EBS to students twice on the same day, five hours apart. Convergent validity was determined by comparing the results of the EBS with 24-hour recalls conducted by trained dietitians. Spearman correlations and kappa statistics were used. Results: The EBS produced acceptable validity and reliability indices. Discussion: The EBS, designed specifically for use with minority urban adolescents who are both economically deprived and attend schools with documented low performance, provided preliminary evidence that it could produce valid and reliable scores with this population. Translation to Health Education Practice: The EBS which is easy for students to use and creates minimal disruption of instructional time can be used by researchers or practitioners to assess eating behaviors in low-income, minority adolescents.

Testing Factorial Invariance of the Amotivation Inventory-Physical Education Across Gender for Urban Adolescents

Lack of motivation, or amotiation, is emerging as a critical issue in high school physical education. The Amotivation Inventory-Physical Education (Shen, Winger, Li, Sun, & Rukavina, 2010) was developed to measure the multidimensional nature of amotivation construct in physical education. This study was designed to examine the consistency of the metric properties of Amotivation Inventory-Physical Education scores by evaluating their factorial structure for invariance across gender in a sample of 985 urban inner-city high school adolescents. Latent mean invariance was also tested. Results revealed that constraining factor loadings and intercepts in sequential configural, metric, and scalar invariances had no meaningful impact on model fit. However, gender might play a role in the magnitude of factor scores. Findings suggest that the four-factor structure of the Amotivation Inventory-Physical Education is a satisfactory representation of motivational deficits for urban inner-city adolescents and provide significant validity evidence for the scale scores in urban high school settings.