According to a new Japanese study, high intakes of vitamin A and vitamin B2 significantly strengthen the body’s ability to transport oxygen to muscles and to generate energy during prolonged exercise.
In the study, the intake of 13 vitamins, minerals and trace elements was assessed via food frequency questionnaires in 373 Japanese men aged 30–69 years (1). In addition, cardiorespiratory fitness (CRF) was tested by measuring the maximum amount of oxygen that the participants were capable of absorbing to generate energy during exercise on a bicycle ergometer. Furthermore, physical activity was measured by collecting step count data for seven consecutive days. The study results showed that while most participants had adequate intakes of vitamin B12, niacin, folate and iron, they had insufficient intakes of vitamin A (61% of participants) and thiamine (81%) as well as of magnesium, calcium and zinc (25-35%). Participants with the best CRF had the highest vitamin A, riboflavin, calcium and overall micronutrient intake compared to participants in the lower CRF categories. These differences remained after adjustment for physical activity, age, BMI and smoking status.
The researchers concluded that higher intakes of several individual micronutrients and overall micronutrient intake status seem to be independently associated with increased CRF. As micronutrients most commonly function as essential coenzymes and cofactors (e.g., in the respiratory chain), adequate intakes are needed to support basic cellular reactions required to maintain energy production.
CRF is defined as the ability of the body to transport oxygen to the muscles and to absorb and use oxygen during prolonged exercise. CRF is influenced by several factors, including age, sex, heredity, body composi-tion and lifestyle factors such as physical activity, smoking status and dietary habits. While several studies have demonstrated that physical activity is related to CRF, fewer reports are available on the potential association between CRF and nutrient (usually macronutrients) intake status.