Athletic Performance: Carrying out of specific physical routines or procedures by one who is trained or skilled in physical activity. Performance is influenced by a combination of physiological, psychological, and socio-cultural factors.Sports: Activities or games, usually involving physical effort or skill. Reasons for engagement in sports include pleasure, competition, and/or financial reward.Doping in Sports: Illegitimate use of substances for a desired effect in competitive sports. It includes humans and animals.Performance-Enhancing Substances: Agents that improve the ability to carry out activities such as athletics, mental endurance, work, and resistance to stress. The substances can include PRESCRIPTION DRUGS; DIETARY SUPPLEMENTS; phytochemicals; and ILLICIT DRUGS.Athletes: Individuals who have developed skills, physical stamina and strength or participants in SPORTS or other physical activities.Sports Medicine: The field of medicine concerned with physical fitness and the diagnosis and treatment of injuries sustained in exercise and sports activities.Flatfoot: A condition in which one or more of the arches of the foot have flattened out.Anabolic Agents: These compounds stimulate anabolism and inhibit catabolism. They stimulate the development of muscle mass, strength, and power.Running: An activity in which the body is propelled by moving the legs rapidly. Running is performed at a moderate to rapid pace and should be differentiated from JOGGING, which is performed at a much slower pace.Physical Endurance: The time span between the beginning of physical activity by an individual and the termination because of exhaustion.Football: A competitive team sport played on a rectangular field. This is the American or Canadian version of the game and also includes the form known as rugby. It does not include non-North American football (= SOCCER).Dietary Supplements: Products in capsule, tablet or liquid form that provide dietary ingredients, and that are intended to be taken by mouth to increase the intake of nutrients. Dietary supplements can include macronutrients, such as proteins, carbohydrates, and fats; and/or MICRONUTRIENTS, such as VITAMINS; MINERALS; and PHYTOCHEMICALS.Exercise: Physical activity which is usually regular and done with the intention of improving or maintaining PHYSICAL FITNESS or HEALTH. Contrast with PHYSICAL EXERTION which is concerned largely with the physiologic and metabolic response to energy expenditure.Muscle, Skeletal: A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.Psychomotor Performance: The coordination of a sensory or ideational (cognitive) process and a motor activity.Task Performance and Analysis: The detailed examination of observable activity or behavior associated with the execution or completion of a required function or unit of work.Caffeine: A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.Ethanol: A clear, colorless liquid rapidly absorbed from the gastrointestinal tract and distributed throughout the body. It has bactericidal activity and is used often as a topical disinfectant. It is widely used as a solvent and preservative in pharmaceutical preparations as well as serving as the primary ingredient in ALCOHOLIC BEVERAGES.PubMed: A bibliographic database that includes MEDLINE as its primary subset. It is produced by the National Center for Biotechnology Information (NCBI), part of the NATIONAL LIBRARY OF MEDICINE. PubMed, which is searchable through NLM's Web site, also includes access to additional citations to selected life sciences journals not in MEDLINE, and links to other resources such as the full-text of articles at participating publishers' Web sites, NCBI's molecular biology databases, and PubMed Central.Periodicals as Topic: A publication issued at stated, more or less regular, intervals.Marijuana Smoking: Inhaling and exhaling the smoke from CANNABIS.BooksPublishing: "The business or profession of the commercial production and issuance of literature" (Webster's 3d). It includes the publisher, publication processes, editing and editors. Production may be by conventional printing methods or by electronic publishing.MEDLINE: The premier bibliographic database of the NATIONAL LIBRARY OF MEDICINE. MEDLINE® (MEDLARS Online) is the primary subset of PUBMED and can be searched on NLM's Web site in PubMed or the NLM Gateway. MEDLINE references are indexed with MEDICAL SUBJECT HEADINGS (MeSH).Heel: The back (or posterior) of the FOOT in PRIMATES, found behind the ANKLE and distal to the TOES.SOX9 Transcription Factor: A SOXE transcription factor that plays a critical role in regulating CHONDROGENESIS; OSTEOGENESIS; and male sex determination. Loss of function of the SOX9 transcription factor due to genetic mutations is a cause of CAMPOMELIC DYSPLASIA.Toes: Any one of five terminal digits of the vertebrate FOOT.Ankle Joint: The joint that is formed by the inferior articular and malleolar articular surfaces of the TIBIA; the malleolar articular surface of the FIBULA; and the medial malleolar, lateral malleolar, and superior surfaces of the TALUS.Ankle: The region of the lower limb between the FOOT and the LEG.Ankle Injuries: Harm or hurt to the ankle or ankle joint usually inflicted by an external source.Foot: The distal extremity of the leg in vertebrates, consisting of the tarsus (ANKLE); METATARSUS; phalanges; and the soft tissues surrounding these bones.Track and Field: Sports performed on a track, field, or arena and including running events and other competitions, such as the pole vault, shot put, etc.Contraceptives, Oral: Compounds, usually hormonal, taken orally in order to block ovulation and prevent the occurrence of pregnancy. The hormones are generally estrogen or progesterone or both.Contraceptives, Oral, Combined: Fixed drug combinations administered orally for contraceptive purposes.Contraceptives, Oral, Synthetic: Oral contraceptives which owe their effectiveness to synthetic preparations.Contraceptives, Oral, Hormonal: Oral contraceptives which owe their effectiveness to hormonal preparations.Ethinyl Estradiol: A semisynthetic alkylated ESTRADIOL with a 17-alpha-ethinyl substitution. It has high estrogenic potency when administered orally, and is often used as the estrogenic component in ORAL CONTRACEPTIVES.Desogestrel: A synthetic progestational hormone used often as the progestogenic component of combined oral contraceptive agents.KentuckyDrugs, Chinese Herbal: Chinese herbal or plant extracts which are used as drugs to treat diseases or promote general well-being. The concept does not include synthesized compounds manufactured in China.Consent Forms: Documents describing a medical treatment or research project, including proposed procedures, risks, and alternatives, that are to be signed by an individual, or the individual's proxy, to indicate his/her understanding of the document and a willingness to undergo the treatment or to participate in the research.Oxidative Stress: A disturbance in the prooxidant-antioxidant balance in favor of the former, leading to potential damage. Indicators of oxidative stress include damaged DNA bases, protein oxidation products, and lipid peroxidation products (Sies, Oxidative Stress, 1991, pxv-xvi).Diet, Gluten-Free: A diet which is devoid of GLUTENS from WHEAT; BARLEY; RYE; and other wheat-related varieties. The diet is designed to reduce exposure to those proteins in gluten that trigger INFLAMMATION of the small intestinal mucosa in patients with CELIAC DISEASE.Anterior Cruciate Ligament: A strong ligament of the knee that originates from the posteromedial portion of the lateral condyle of the femur, passes anteriorly and inferiorly between the condyles, and attaches to the depression in front of the intercondylar eminence of the tibia.Knee Injuries: Injuries to the knee or the knee joint.Wounds and Injuries: Damage inflicted on the body as the direct or indirect result of an external force, with or without disruption of structural continuity.Accident Prevention: Efforts and designs to reduce the incidence of unexpected undesirable events in various environments and situations.Ejaculation: The emission of SEMEN to the exterior, resulting from the contraction of muscles surrounding the male internal urogenital ducts.Premature Ejaculation: The emission of SEMEN and seminal fluid during the act of preparation for sexual intercourse, i.e. before there is penetration, or shortly after penetration.Bread: Baked food product made of flour or meal that is moistened, kneaded, and sometimes fermented. A major food since prehistoric times, it has been made in various forms using a variety of ingredients and methods.Vitamins: Organic substances that are required in small amounts for maintenance and growth, but which cannot be manufactured by the human body.Minerals: Native, inorganic or fossilized organic substances having a definite chemical composition and formed by inorganic reactions. They may occur as individual crystals or may be disseminated in some other mineral or rock. (Grant & Hackh's Chemical Dictionary, 5th ed; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Secale cereale: A hardy grain crop, rye, grown in northern climates. It is the most frequent host to ergot (CLAVICEPS), the toxic fungus. Its hybrid with TRITICUM is TRITICALE, another grain.Triticum: A plant genus of the family POACEAE that is the source of EDIBLE GRAIN. A hybrid with rye (SECALE CEREALE) is called TRITICALE. The seed is ground into FLOUR and used to make BREAD, and is the source of WHEAT GERM AGGLUTININS.Flour: Ground up seed of WHEAT.