I understand the threads about temperature and its effect on string tension. My question is - do you need to warm up your strings before you play? Do they loosen up as you play with them or will the effect be negligible compared to the effect of the ambient room temperature? During the winter, I see some players placing their hands over the sweet spot before first playing. Last year we had to play in a hall with a broken heating system and when it was below freezing, the number of string breakages was ridiculous. When you whack a shuttle with the strings, the energy is converted into kinetic energy and sound, but does some of it get absorbed as heat, or will the string always remain the same as the air around it?
Unless your racket is freezing or burning hot, I would not worry so much about the string bed. And if it is freezing or burning hot, just let the racket warm-up or cool down to room temperature, then play.
The shuttle impact causes the string to stretch. This stretching causes heat. When the heat is high enough, the string fibres will melt in the microscopic scale in the stretched state. The melting quickly cools and causes the string to resolidify in the stretched state. So gradually the string fibre becomes longer and thinner, eventually thin enough to break. In cold temperatures, everything become brittle and shatters easily. Badminton strings are affected in the same way.
Erm, I don't think that happens, actually I don't believe the minute amount of heat generated by string stretching is ever going to be high enough to melt the string, even on "the microscopic scale". (And what does "melting on the microscopic scale" mean anyway? Melting and resetting is the dissolution of some existing molecular bonds, followed by the formation of other molecular bonds. All melting is on the molecular level.) Is this your own theory, or do you have a source for it? Strings mainly deform elastically, although tension loss might be due to plastic deformation. I don't know enough to say. Plastic deformation is not primarily due to heat. A string may be stretched very slowly beyond its elastic limit, thereby dissipating all generated heat so that it never "builds up" to melting temperature, yet still the string undergoes plastic deformation. That said, heat and cold certainly influence the characteristics of materials, and obviously we should avoid storing our rackets in very cold or very hot places.
