/// <summary>
/// Gets the gender-filtered and age-filtered leaderboard of a segment. This method requires the currently authenticated
/// athlete to have a Strava premium account.
/// </summary>
/// <param name="segmentId">The Strava segment Id.</param>
/// <param name="gender">The gender used to filter the leaderboard.</param>
/// /// <param name="age">The age range used to filter the leaderboard.</param>
/// <returns>The leaderboard filtered by gender and age.</returns>
public Leaderboard GetSegmentLeaderboard(String segmentId, Gender gender, AgeGroup age)
{
String getUrl = String.Format("{0}/{1}/leaderboard?gender={2}&age_group={3}&filter=age_group&access_token={4}",
Endpoints.Leaderboard,
segmentId,
gender.ToString().Substring(0, 1),
UrlHelper.AgeGroupToString(age),
Authentication.AccessToken
);
String json = WebRequest.SendGet(new Uri(getUrl));
return(Unmarshaller <Leaderboard> .Unmarshal(json));
}