RESUMO
The dominance of Jamaican sprinters in international meets remains largely unexplained. Proposed explanations include demographics and favorable physiological characteristics. The aim of this study was to analyze the demographic characteristics of world class Jamaican sprinters. Questionnaires administered to 120 members of the Jamaican national team and 125 controls elicited information on place of birth, language, ethnicity, and distance and method of travel to school. Athletes were divided into three groups based on athletic disciplines: sprint (s: 100-400 m; n = 80), jump and throw (j/t: jump and throw; n = 25) and, middle distance (md: 800-3000 m; n = 15). Frequency differences between groups were assessed using chi-square tests. Regional or county distribution of sprint differed from that of middle distance (P < 0.001) but not from that of jump and throw athletes (P = 0.24) and that of controls (P = 0.59). Sprint athletes predominantly originated from the Surrey county (s = 46%, j/t = 37%, md = 17, C = 53%), whilst middle distance athletes exhibited excess from the Middlesex county (md = 60%). The language distribution of all groups showed uniformity with a predominance of English. A higher proportion of middle distance and jump and throw athletes walked to school (md = 80%, j/t = 52%, s = 10%, and C = 12%) and travelled greater distances to school. In conclusion, Jamaica's success in sprinting may be related to environmental and social factors.
Assuntos
Corrida/fisiologia , Corrida/estatística & dados numéricos , Adolescente , Adulto , Distribuição por Idade , Feminino , Humanos , Jamaica/etnologia , Masculino , Distribuição por Sexo , Fatores Socioeconômicos , Adulto JovemRESUMO
UNLABELLED: The angiotensin-converting enzyme (ACE) and the alpha-actinin-3 (ACTN3) genes are two of the most studied "performance genes" and both have been associated with sprint/power phenotypes and elite performance. PURPOSE: To investigate the association between the ACE and the ACTN3 genotypes and sprint athlete status in elite Jamaican and US African American sprinters. METHODS: The ACTN3 R577X and the ACE I/D and A22982G (rs4363) genotype distributions of elite Jamaican (J-A; N = 116) and US sprinters (US-A; N = 114) were compared with controls from the Jamaican (J-C; N = 311) and US African American (US-C; N = 191) populations. Frequency differences between groups were assessed by exact test. RESULTS: For ACTN3, the XX genotype was found to be at very low frequency in both athlete and control cohorts (J-C = 2%, J-A = 3%, US-C = 4%, US-A = 2%). Athletes did not differ from controls in ACTN3 genotype distribution (J, P = 0.87; US, P = 0.58). Similarly, neither US nor Jamaican athletes differed from controls in genotype at ACE I/D (J, P = 0.44; US, P = 0.37). Jamaican athletes did not differ from controls for A22982G genotype (P = 0.28), although US sprinters did (P = 0.029), displaying an excess of heterozygotes relative to controls but no excess of GG homozygotes (US-C = 22%, US-A = 18%). CONCLUSIONS: Given that ACTN3 XX genotype is negatively associated with elite sprint athlete status, the underlying low frequency in these populations eliminates the possibility of replicating this association in Jamaican and US African American sprinters. The finding of no excess in ACE DD or GG genotypes in elite sprint athletes relative to controls suggests that ACE genotype is not a determinant of elite sprint athlete status.
Assuntos
Actinina/genética , Atletas , População Negra/genética , Peptidil Dipeptidase A/genética , Esportes/fisiologia , Adulto , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Jamaica , Masculino , Estados UnidosRESUMO
The west Indians have a sports heritage which we must protect and enhance. Sports is considered a part of education. Many of us in the caribbean either studied physical education or played some sport in England. therefore, our programmes in physical education and sports are originally patterned on the British. In 1944, two supervisors of physical training, Mr. I.G.P. Hugh and Miss Bach from Great Britain, were provided under the colonial Development and Welfare Act for the improvement and modernization of physical training throughout the schools in Jamaica. The then Director of Education, Mr. B.H. Easter, organized a conference of heads of training colleges with a view to drawing up a programme for physical training in the teacher training colleges. Subsequently, in-service training courses in physical training were conducted at various centres throughout the island and syllabuses for infant, lower middle and upper divisions, as they were then called, were compiled and distributed to the infant and elementary schools for the guidance of teachers. These syllabuses were based on the historic 1933 syllabus of physical training in England. At the expiration of the contracts two supervisors, a male and a female, were appointed to continue the programme in Jamaica. The curriculum then consisted of physical exercises, cricket, netball, major games, athletics and some folk and country dancing. By the early fifties, in-service teachers were being awarded scholarship annually to pursue one year supplementary courses in physical education under the British Commonwealth Scholarship Scheme. One such teacher was hired by the Ministry of Education as an Education Officer for physical education in 1956. since then, the scope of physical education has been widened and it now embraces a comprehensive range of physical activities including movement education, educational gymnastics, games (major and minor), athletics (i.e. track and field), dance (modern, educational, folk, etc.), aquatics (swimming and life saving), camping and hiking.(AU)
Assuntos
Esportes/tendências , Educação Física e Treinamento/história , JamaicaRESUMO
The benefits of exercise are far-reaching. Various studies have demonstrated that regular aerobic exercise reduces the risk of death due to heart disease and stroke. It also aids in reducing weight and helps to prevent diabetes mellitus. Exercise strengthens bones by increasing calcium uptake and it also enhances immunity function. It strengthens muscles, including heart muscle, and is associated with lower blood pressure and cholesterol levels. The psychological benefits are also broad, and most studies suggest a positive relationship between physical fitness and mental achievement. Exercise is relaxing to the mind. It improves the mental tone of an individual in the same way that it improves the physical tone of the body. Psychologically, regular exercise is thought to contribute to a feeling of well-being, as well as to help relieve stress. There has been a marked change in health and nutrition in the Caribbean over the last 30 to 40 years. A large proportion of the United States population is obese, and the major cause is a lack of physical activity. In some Caribbean countries, one-half of the adult females and one-fourth of the adult males are obese. Some school children are also obese, although the rates are much lower than in adults. This could be 10 to 20 percent. Lifestyle related chronic diseases: Experience in many countries shows that children can be taught to practice a healthy lifestyle and that a healthy lifestyle can reduce the risk factors for chronic diseases such as diabetes and hypertension. While the biological or physiological facts of lifestyle development learnt in other countries can apply in the Caribbean, their application has to be learnt in our own environment. Positive healthy lifestyle development implies: keeping body fat low; eating correctly; performing adequate daily physical exercise; not smoking; avoiding substance abuse, including alcohol; developing a positive self-concept and improving self-esteem. It was against this background that the school-based Community Nutrition Education Programme, otherwise called Project Lifestyle, was initiated in 1988 by the Caribbean Food and Nutrition Institute (CFNI) at the UWI, Mona Campus. It was hoped that in the long run the initiative would help to prevent obesity, diabetes, hypertension and other lifestyle related chronic diseases.(AU)