Bradley J. Cardinal

Ginseng does not Enhance Psychological Well-Being in Healthy, Young Adults: Results of a Double-Blind, Placebo-Controlled, Randomized Clinical Trial

OBJECTIVE Ginseng is a popular, commercially available dietary supplement that is purported to have a number of psychological benefits. The purpose of this study was to examine these claims, with specific reference to ginsengs effects on affect and mood. DESIGN Prospective, double-blind, placebo-controlled, randomized clinical trial. PARTICIPANTS/SETTING Eighty-three adults (40 women, 43 men) participated in this study (mean age = 25.7 year). Participants were recruited from within a university community and at area health clubs. INTERVENTION Participants were randomly assigned to one of three experimental conditions: placebo (lactose), 200 mg ginseng, or 400 mg ginseng. The ginseng preparation used in this study consisted of the Panax ginseng C A Meyer concentrate G115 in capsular format. Each participant was given a 60-day allotment of their respective supplement along with written instructions about the proper intake and storage of the capsules during the 8-week study period. MAIN OUTCOME MEASURES Positive affect, negative affect, and total mood disturbance. Measures were obtained pre- and post-intervention. STATISTICAL ANALYSES PERFORMED Repeated measures multivariate analysis of variance was used. Because there were three dependent variables, and in an effort to minimize the experimentwise-error rate, alpha was adjusted using the Bonferroni technique (i.e., P < .05/3 = P < .016). RESULTS Ginseng supplementation had no effect on positive affect, negative affect, or total mood disturbance (all P > .016). CONCLUSION The present findings do not support claims that chronic ginseng supplementation--at either its clinically recommended level or at twice that level--enhances affect or mood in healthy young adults.

DEVELOPMENT AND EVALUATION OF STAGE-MATCHED WRITTEN MATERIALS ABOUT LIFESTYLE AND STRUCTURED PHYSICAL ACTIVITY

Two sets of written materials about physical activity were developed, one promoting lifestyle exercise and the other promoting structured exercise. Both sets integrated the Transtheoretical Model of behavior-change concepts. Materials were evaluated by 8 women and 6 men (M age = 63.1 yr.) using a stratified (by gender) randomized group design. Participants evaluated the materials on 8 factors of a standardized instrument. Cronbach alpha was .97. No significant differences were found between the two sets of materials on the 8 factors evaluated. Effect size differences ranged from .16 to .84 (M =.46).

Readability and Comprehensibility of the “Exercise Lite” Brochure

Studies suggest that exercise literature tends to be very difficult to read and the writing not matched to the reading ability of the audience for which it was intended. Two studies aimed at describing the readability and comprehensibility of the recently developed U.S. Centers for Disease Control and American College of Sports Medicine “Exercise Lite” brochure were conducted. In Study 1, the brochures readability was assessed using four different formulas. This study showed that the brochure was written at a level equivalent to that of a scientific journal article. In Study 2, 56 participants (two-thirds of whom were college graduates) were tested to assess whether they could comprehend the brochures message. Results showed that, without supplemental instruction, the Exercise Lite brochure was incomprehensible for 69.6% (n = 39) of the subjects.

READABILITY ANALYSIS OF HEALTH, PHYSICAL EDUCATION RECREATION AND DANCE JOURNAL ARTICLES

The readability levels of 10 articles each from the Journal of Health Education, Journal of Physical Education, Recreation and Dance, Research Quarterly for Exercise and Sport, and Strategies: A Journal for Physical and Sport Educators were estimated. On average, the 40 articles were written at the college junior level (M = 14.9, SD = 1.6); however, significant between-journal differences were found, with between-journal effect sizes ranging from 0.36 to 3.64.