Teenagers with adequate blood concentrations of beta-carotene and vitamins A, C, D and E perform better in physical fitness tests than those with low concentrations, a Spanish study suggests.
In the epidemiological study, blood samples of 1089 participants across Europe aged 12 to 17 were tested for a variety of micronutrients, including vitamin A (retinol), beta-carotene, vitamin C, vitamin E (alpha-tocophe-rol), vitamin B6, folate, vitamin D and iron (1). The volunteers' physical fitness was assessed through two tests: a standing long jump test, which assesses lower body muscular strength, and a 65-foot (19.8-metre) shuttle run test, which assesses cardiovascular fitness through maximal oxygen consumption. The study results showed that the blood micronutrient levels were closely connected with the participants' performance on the physical fitness tests. For cardiorespiratory fitness, increased concentrations of iron (hemoglobin), and vitamins A and C in males and beta-carotene and vitamin D in females were associated with maximal oxygen consumption. For muscular fitness, higher concentrations of beta-carotene, and vitamins A and vitamin E in males and beta-carotene and vitamin D in females were associated with performing better on the standing long jump test.
The researchers commented that the associations between physical fitness and iron or vitamin status observed in the adolescents should be followed up by a study specifically designed to evaluate causal relationships. They added that adolescence is a critical period of growth and development and for the acquisition of healthy behaviors. Therefore, appropriate nutrition during this period is a basic prerequisite for exploiting one’s full genetic potential that, together with physical activity, will influence health outcomes in later adult life. Scientific evidence shows that adolescents' performance in physical fitness tests has declined in the last three decades. For some micronutrients, an at least marginally deficient nutritional status has also been identified. It has been stated that physical fitness and nutritional status of the individuals are closely related (2). Nonetheless, this relationship can still differ according to sex, age, latitude, ethnicity, climate, seasonality, genetic background, adiposity, and lifestyle factors.