Book excerpt: Explore the emerging field of free radical biology, exercise, and aging with this definitive reference. Free Radicals in Exercise and Agingaddresses the current debate regarding whether free radicals released during exercise accelerate the aging process. It explains how free radicals can serve as important regulators of aerobic processes, and it clarifies the importance of exercise in increasing the efficiency of the antioxidant and oxidative repair systems. Mounting research data indicate that free radicals are involved in a variety of physiological and pathophysiological processes. This book focuses on exercise-induced adaptation. In general, a person's ability to adapt to internal and external changes decreases during the aging process. However, by continually exposing the body to different challenges, regular exercise triggers an adaptation process that keeps the body and mind fit. Free Radicals in Exercise and Agingelucidates the role of free radical species in regulating this process. This text is also one of the first to provide an in-depth review of skeletal muscle oxidative stress and aging. This issue is pivotal because muscle serves such a critical role in mobility and normal life. Free Radicals in Exercise and Aging shares the most current understanding of how reactive oxygen species influence the biology of skeletal muscles. It explores some of the unique characteristics that skeletal muscle displays during aging, both in terms of free radical production and with regard to antioxidant systems. The implications of this research are far-reaching. Mutation of DNA is linked very closely to cancer, and if regular exercise improves the regulation of the antioxidant systems and the oxidative damage repair system, these mechanisms may be a very important tool against this deadly disease. This research-oriented text presents the latest information on the subject. It reviews and critiques current literature and provides critical information for exercise physiologists, sports medicine specialists, sport nutritionists, and gerontologists.