a carbohydrate-rich diet is of benefit for the
athlete before an event.
Conclusion
From the available literature, based on human
studies, it seems fair to conclude the following.
1 An acute increase in the availability of circulat-
ing fatty acids does not result in any clear effects
on endurance performance.
2 Short-term ingestion of a fat-rich diet (3–5
days) leads to a deterioration of endurance per-
formance when compared with ingestion of a
carbohydrate-rich diet.
3 Adaptation to a fat-rich diet, in combination
with training, for a period of 1–4 weeks does not
attenuate endurance performance compared
with adaptation to a diet rich in carbohydrates,
but when dieting and training are continued for
7 weeks, endurance performance is markedly
better when a carbohydrate-rich diet is
consumed.
4 No benefit is obtained when switching to a car-
bohydrate-rich diet after long-term adaptation to
a fat-rich diet, compared with when a carbohy-
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* *1000806020Time (weeks)Time to exhaustion (min)7 840120**Fig. 14.4Endurance performance to exhaustion
measured on a Krogh bicycle ergometer after 7 weeks’
training on a fat-rich diet ( ) or a carbohydrate-rich
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