The age of female puberty appears to have decreased in the United States and western countries as child health and nutrition have improved and obesity has become more prevalent. Also, environmental contaminants, particularly endocrine disruptors, may also play a role in lowering the age of puberty. Puberty at an early age increases the risk of…

This article discusses the limitations of 14 randomized controlled trials of exercise rehabilitation for patients who sustained myocardial infarction. The difficulty of sampling patients and controlling the sample size is discussed and the benefits of pooled statistical evidence are considered. (JL)

This article surveys recent research on how and when exercise or estrogen therapy should be used to treat or prevent athletic amenorrhea, osteoporosis, cancer, and heart disease. The suspected causes of each disease are discussed and the benefits and dangers of each form of treatment/prevention are weighed. (JL)

Presents data from recent studies on exercise and fitness as they influence the risk of all-cause mortality and cardiovascular disease (CVD). Results show that individuals who have or adopt higher physical activity and fitness levels lower the risk of CVD, live longer, and improve their quality of life. (SM)