I did not want to stop swimming, and wanted to check whether I could double my usual these days distance. I did not care much about the style and speed, I just wanted to move forward in water, because nothing better waited for me outside on this emotionally excruciating day.
264 length (25 yards), 6 km total, in almost 3:07 (187 minutes). Six kilometers should constitute 4 swimmer's miles. First 200 I made in 2:20, first 5 km - in 2:35 (155 minutes).
Compared to the similar distance swims in the ocean, where the main problem was dropping of the body temperature by the third hour despite keeping the same speed (more or less), swimming in pool for so long irritated my skin. I inhaled too much chlorine! There also was a need to change lanes to give the space for team training, and the constant turning became annoying.
The great thing was to see the pool with lights after darkness, it was fun to swim towards a black cross on the wall with two lamps on the sides.
The protein digestibility-corrected amino acid score (PDCAAS) has been adopted by FAO/WHO as the preferred method for the measurement of the protein value in human nutrition.
PDCAAS = Amino Acid Score x Digestibility
The method is based on comparison of the concentration of the first limiting essential amino acid in the test protein with the concentration of that amino acid in a reference (scoring) pattern. This scoring pattern is derived from the essential amino acid requirements of the preschool-age child.
Although the principle of the PDCAAS method has been widely accepted, critical questions have been raised in the scientific community:
the validity of the preschool-age child amino acid requirement values (more than 4 times greater than the EAA requirement for an adult),
the validity of correction for fecal instead of ileal digestibility,
the truncation of PDCAAS values to 100%.
The reference scoring pattern was based on studies performed more than 25 years ago on a limited number of 2-year-old children recovering from malnutrition.
According to the current official recommendations, a 2-year old child needs ~ 3x higher essential-to-non-essential amino acid ratio, and needs essential amino acids in different proportions than adult. Methionine/cysteine is the limiting essential amino acids for adults, and for children it is lysine or tryptophan.
The use of fecal digestibility overestimates the nutritional value of a protein because amino acid nitrogen entering the colon is lost for protein synthesis in the body and is, at least in part, excreted in urine as ammonia.