Good luck with the training programme Pea. Keep in touch and let us know how you are doing.
There are 5 virtues according to Confucius. 5 notes in the pentatonic (hence the penta) scale (most popular scale in western music). There are 5 natural senses (sight, hearing, smell, touch, and taste). There are also 5 elements (fire, air, water, earth, and spirit) as well.
I think it is the number we are in line for a gang-bang on some unsuspecting NAFs that loves AFs.