availability and CHO oxidation, does not always
enhance exercise performance (McConell et al.
1996). From a practical perspective, because ath-
letes are unable to assess the level of their carbo-
hydrate reserves and their likely point of fatigue,
CHO (and fluid) replacement should commence
early and continue throughout exercise.
Conclusion
In view of the importance of CHO for contracting
skeletal muscle during strenuous exercise, CHO
should be ingested to maintain CHO availability
and high rates of CHO oxidation. Such a strategy
results in enhanced endurance performance.
There appear to be few differences between
glucose, sucrose and maltodextrins, as sources of
CHO, in their effects on exercise metabolism and
performance, while fructose alone is not an effec-
tive CHO supplement. Enough CHO should be
ingested to supply CHO to contracting muscle at
about 30–60 g · h–1, without negative effects on
fluid bioavailability.
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