Although understanding of the unique physiology of the female athlete has increased,
there are still many unanswered questions. Both endogenous and exogenous female sex
steroids can in fl uence numerous cardiovascular, respiratory, and metabolic variables,
but most likely have minimal impact on the athletic ability of most recreational athletes.
In elite athletes, however, even a statistically nonsigni fi cant change can mean the critical
difference between fi rst and second place. There appears to be individual variability in
the response of different performance parameters to MC phase and/or OC administration.
In particular, there may be subtle alterations in substrate metabolism, and increased
susceptibility to heat stress under conditions of high heat and humidity. The latter is
most important for female athletes competing in endurance events. Similarly, MC phase
and OC use may have some implications in terms of management of MLA, preventio