It's doesn't really matter what string tension they use... & focus on yourself... Don't mimic their string tension or you will just end up hurting yourself.
Ok. thanks. is there a relation of reaction speed with the tension of the strings? eg. high reaction speed players to string higher tension ?
Lots of other factors in relation to reaction speed. Racquet weight and shaft tension, racquet balance etc
mostly it is related to power and precision. lower tension means it can provide more power with cost of precision. higher tension mean you need to spend more power, but you know exactly where it will gonna fall. (imagine playing badminton with a plank of wood, it will not gonna bounce and causing a random unknown factor). the pros have the power, what they need is precision, but for us, we need to compensate the precision for power because really, can you play with a plank of wood? usually people go from 21-28, so 27 is actually already on a high side, my string tension is around 23-24lbs
Its a matter of personal preference. Choice of racket also affects how one feel bout the string tension. As a general rule of thumb, if u could clear effortlessly frm ur back line to the other side's back line with less than 90% strength, then that tension shouldnt pose a problem.
good explanation there..i always thought higher tension will require less strength. in fact its the opposite..no wonder when i hit it require more strength to clear the shuttles..but i do feel my shuttle is more precise when i smash or drop shot..
also think Asia or warmer countries have their rackets string higher in general. In canada especially in winter, lower tension just to prevent frequent string snap when racket transition from cold to warm. Actually most of the clubs here turn their heat at minimum even when its -20 outside...