The U.S. Army Physical Fitness School (USAPFS): Develops doctrine, conducts research, and provides training assistance with the ultimate objective "to enhance combat readiness by developing and sustaining a high level of physical fitness in soldiers". Site includes FM 21-20 and additional Army Fitness documents.
The Cooper Institute: Aworld renowned organization dedicated to advancing the understanding of the relationship between living habits and health and to providing leadership in implementing these concepts to enhance the physical and emotional well-being of individuals. Considered by many to be the authority on aerobic fitness.
The American Academy of Orthopaedic Surgeons (AAOS): Provides education and practice management services for orthopaedic surgeons and allied health professionals. It also serves to inform the public about the science of orthopaedics.
The American College of Sports Medicine (ACSM): The largest sports medicine and exercise science organization in the world. A great source of information regarding the latest advances in exercise science as well as providing the most highly sought and accepted certifications for exercise fitness professionals available in this field.
The American Orthopaedic Society for Sports Medicine (AOSSM): Promotes and supports educational and research programs in sports medicine for both improvement in fitness performance as well as injury prevention and management. http://www.sportsmed.org/
The American Physical Therapy Association (APTA): A national professional organization of physical therapists, physical therapy assistants, and students. The site provides information on physical therapy practice and educational materials.
The National Athletic Trainers Association (NATA): Advances the athletic training profession and provides information for athletic trainers and the public in the areas of prevention, evaluation, management, and rehabilitation of injuries.
The National Strength and Conditioning Association (NSCA): An educational association which develops and presents information regarding strength training and conditioning practices, injury prevention, and research findings.
The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS): Provides educational materials about various forms of arthritis and rheumatic disease and bone, join, and skin diseases.
Peak Performance: A sport oriented website containing a plethora of well documented sport training techniques. Some of the topics include nutrition, plyometric training, sport psychology and many references to training for specific sports.