Exercise,nutrition and immune function

Strenuous bouts of prolonged exercise and heavy training are associated with depressed immune cell function. Furthermore, inadequate or inappropriate nutrition can compound the negative influence of heavy exertion on immunocompetence. Dietary deficiencies of protein and specific micronutrients have long been associated with immune dysfunction. An adequate intake of iron, zinc and vitamins A, E, B6 and B12 is particularly important for the maintenance of immune function, but excess intakes of some micronutrients can also impair immune function and have other adverse effects on health. Immune system depression has also been associated with an excess intake of fat. To maintain immune function, athletes should eat a well-balanced diet sufficient to meet their energy requirements. An athlete exercising in a carbohydrate-depleted state experiences larger increases in circulating stress hormones and a greater perturbation of several immune function indices. Conversely, consuming 30–60?g carbohydrate?·?h^?1 during sustained intensive exercise attenuates rises in stress hormones such as cortisol and appears to limit the degree of exercise-induced immune depression. Convincing evidence that so-called ‘immune-boosting’ supplements, including high doses of antioxidant vitamins, glutamine, zinc, probiotics and Echinacea, prevent exercise-induced immune impairment is currently lacking.     

Why do children not play in nearby nature? Results from a Norwegian survey

Based on a nationwide Norwegian survey among 3160 parents of children aged 6–12 years, this article identifies and discusses barriers for children’s engagement with nearby nature. A set of social factors related to time pressure are evaluated as more significant barriers than environmental factors such as accessibility, safety and landscape quality. Children’s free play in nearby nature does not seem to be an alternative to a target-orientated and time-scheduled everyday life. Instead, parents give themselves, other adults and public institutions more responsibility to stimulate increased nature contact. Despite strong traditions in outdoor life and good accessibility to nearby nature, social and cultural trends seem to influence children’s engagement with nature in the same way in ‘Green Norway’ as it does in many other European countries. Implications of the findings are discussed in terms of policy and promotion according to nature management and adults’ roles.