This summary is from the IAAF 2nd International Consensus Conference on “Nutrition for Athletics“ held in Monaco from April 18-20, 2007. Copies of the CD and booklet are available from the IAAF website www.iaaf.org.
Nutrition for Travel
Presenter: Tom Reilly (GBR)
Travel across time zones and jet lag can have a profound effect on sleep, digestion, well-being and performance. It is easier to travel westbound than eastbound, since our biological rhythm in “free-running” conditions spans about 25 hours.
Pharmacological approaches for dealing with time changes are not recommended for athletes and emphasis should be laid on behavioral strategies. Athletes should strive to arrive in the new time zone well in advance of their event. Pre-adjustment to the new time zone can be commenced before departure by going to bed either early for eastbound flights or late for westbound flights. Light and exercise can have influence on the circadian rhythm.
The influence of diet remains equivocal. Adequate timing of meals, adjusted to the new time zone, can have an effect. At this time, timing seems much more important than macronutrient content of the meals.
Athletes are prone to dehydration because a lot of fluid is lost just by breathing the dry air in an airplane. An estimate fluid intake of 1520cl/hour should be acceptable. Habitual coffee consumers can take coffee in moderation. Alcohol should be avoided. Athletes should be encouraged to bring their own food supplies to compensate for the menu provided by the airline that is often low in volume and fibre.
Exposure to light or avoidance of light can be a powerful tool for adjustment to the new time zone. Training can have an effect on adjustment, but it seems to be more powerful for phase delay (eastbound) than for phase advance (westbound).
Caffeine is often used, but the effects are ambivalent: it reduces daytime sleepiness, but also impairs recovery time. Sleeping agents are often advocated. Because the right timing of intake is difficult, the advantages are equivocal.
Athletes can face several challenges at the destination of travel. Changed environmental factors, like heat or altitude, reduced or enhanced (all you can eat buffets) access to foods, eating from fast food restaurants or other facilities not tailored to the needs of the athletes, reduced hygiene standards, all make it difficult for athletes to maintain a healthy diet. Meal plans and timing should be organised in advance. Portable and non-perishable foods can be taken along to replace important items that otherwise would be missing. A broad spectrum, low dose multivitamin/mineral supplement can be given to compensate for restricted intake of nutrient rich foods.
As many as 60% of athletes who travel internationally develop diarrhea. Performance may be affected during an attack and for some time afterwards. Athletes should avoid high risk foods and tap water, even for brushing teeth. Personal hygiene, especially washing hands before meals, is important to lower the risk. Treatment is symptomatic in most cases. Fluid and electrolyte should be replaced. A bland diet low in fat and avoiding dairy and alcohol is recommended. If the condition is severe or persists for more than 48 hours antibiotics may be required.
The above summary was written by Peter Res
If you wish to download this handy Grams and Calorie Calculator for Carbohydrate, Protein, and Fat, click here for the Excel spreadsheet.
This is part 13 of 14 in a series from the 2007 2nd IAAF International Consensus Conference “Nutrition for Athletics”