The best swimmers among female Ironman triathletes complete the swimming portion of the event in 50 minutes to an hour. At the World Championship, the cutoff time for all competitors is two hours, 20 minutes. Any participant who fails to complete the 2.2-mile swim within that time is eliminated from the competition.
There are two sources of this essential vitamin, including vitamin K1, or phylloquinone which is primarily found in green leafy vegetables and vitamin K2 or menaquinone which is synthesized by certain intestinal bacteria.
Vitamin BB6 was discovered by Paul Gyorgy in 1934. The Scottish naval surgeon James Lindin observed in 1747 that a nutrient in citrus foods, now known to be Vitamin C, prevented scurvy. Vitamin C was rediscovered by Norwegians, A. Hoist and T. Froelich in 1912.