The key to nutrition, and sports nutrition in particular, is to feed the body’s cells the nutrients it needs to thrive and to repair damage efficiently.
Exercise has both positive and negative effects on the body and in particular the immune system. Research shows that moderate exercise stimulates the immune system but intense training can have the opposite effect, in severe cases pushing the body into autoimmune mode where the body in effect treats components of it own tissues as foreign and attacks them. It is ironic then that sugar in the form of sports drinks, carb snacks, etc, should feature so strongly in an athlete’s diet as they are major immune suppressants. Intense exercise can also promote an increase in free-radical generation and elevated cortisol levels.
So, what role does nutrition play?
Carbohydrates and fats are oxidised to provide energy during exercise. The intensity of the activity will determine which of these will be the predominant fuel source. Low intensity exercise uses free fatty acids first and muscle glycogen second. As intensity increases, glycogen becomes the main fuel source.
Diets high in carbohydrate stimulate muscles to store more glucose and may increase endurance. Athletes consuming 60-70 per cent of calories from carbohydrate are better able to build large reserves of glycogen than those consuming 40 per cent of calories from carbohydrate.
For endurance athletes, recommendations are for 75 per cent of calories to come from carbohydrates which could be 500-600g each day. Fat intake should be limited to 20-30 per cent of total calories.
Nutrition is highly individual depending on the person’s needs and level of fitness, but a few general guidelines include:
Eat more whole grains and fewer refined grains and sugars.
Whole grains, fruits and vegetables should be the bulk of an athlete’s diet.
Eat more vegetarian sources of protein and fewer animal products.
Get more unsaturated fat and less saturated and trans fatty acids.
Lastly best of luck to everyone competing this year!
Lynda McFarland is a nutritional therapist offering individual sports nutrition consultations in Athlone Regional Sports Centre. For appointments, phone (087 ) 7927471.
In conjunction with this year’s triAthlone 2009, Athlone Regional Sports Centre will be hosting an information evening on Thursday July 9 at 7.30pm. Guest speakers on the night include Liam Heavin, triAthlone 2009; Lynda McFarland, nutritional therapist at Athlone Regional Sports Centre; and Charlie Naughton, swim instructor Athlone Regional Sports Centre. It is also hoped to have a cyclist, runner, and physio in attendance to give participants tips that will ensure they will get around the course safely and within their best time. All triathletes are invited to attend this information evening and must RSVP before July 7. Places will be limited.
For further information contact Margo Redmond, Athlone Regional Sports Centre, on (090 ) 6470975 ext 2.