Anabolic-Androgenic Steroids: Incidence of Use and Health Implications
Charles E. Yesalis and Michael S. Bahrke
Is Ginseng an Ergogenic Aid?
Michael S. Bahrke, William P. Morgan, and Aaron Stegner
Ginseng is one of the most popular herbal supplements in the world. Although it is used for the treatment and prevention of many ailments, it is also used to increase work efficiency and is purported to increase energy and physical stamina. Athletes use ginseng for its alleged performance-enhancing attributes. However, many studies examining the pharmacological effects of ginseng on physical performance have not employed sound scientific design and methodology. The purpose of this review is to provide an update on published empirical research focusing primarily on the efficacy of ginseng with respect to physical and athletic performance. Despite attempts in recent investigations to improve on the scientific rigor used in examining the ergogenic properties of ginseng, the authors conclude that many of the same methodological shortcomings observed in earlier studies persist. Enhanced physical performance after ginseng administration in well-designed investigations remains to be demonstrated.
Influence of Age and Body Mass Index on Measures of Physical Fitness in U.S. Army Soldiers
Joseph J. Knapik, Bruce H. Jones, James A. Vogel, Louis E. Banderet, Michael S. Bahrke, and John S. O’Connor
This study describes associations between age, body mass index (BMI), and performance on three common measures of physical fitness: maximum pushups in 2 min, maximum sit-ups in 2 min, and 3.2-km run for time. Subjects were 5,346 healthy male soldiers, ages 18 to 53 years. Before age 30, there were few age-related differences between the youngest and the older age groups on any test; after age 30, performance declined as age increased, averaging 16%, 17%, and 7% per decade for push-ups, sit-ups, and the run, respectively. Regression analysis showed that age accounted for 10%, 15% and 9% of the variance in push-up, sit-up, and run performances, respectively. When BMI was added to the regression model it increased the variance accounted for in the run to 16% (age plus BMI) but did not explain variance in push-ups or sit-ups. There are systematic age-related declines in the performance of push-ups, sit-ups, and 3.2-km running, with age alone accounting for only 9% to 15% of the total performance variance in this sample of healthy men.