former world champion Han Jian went to Guangzhou to watch an top level amateur badminton tournament. among the invitation guests were Hendrawan (ex-INA, WC 2001) and Yu Jinhao (ex-CHN).
here are some exerpts of Han Jian's comment on amateur players.
"not enough warmup is the common problem with amateur badminton, overtime, injuries will start to creep in.
"lacking in strength training. "look at all these amateurs on court, many of them have knee straps, why? because their joints are not strong enough, this is because they didn't have sufficient strength training. professionals won't make this mistake. i insist on doing strength training once of twice a week.
"lack of regular training schedule is another problem with amateurs. sometimes they stop for 2-3 weeks, then suddenly play intensively for 4-5 hours. this irregularity do more harm than good.
lack of shuttle fine control techniques. there are two problem, "not enough training time, just now when they played against Hendrawan / Yu Jinhao, their smashes and clears are not much different already, the only insufficient elements are the fine control shots like the netshot. they have not spent enough time drilling on these shots like the profressionals. this separates the pros and amateur.
the second point is that the correct techniques needs to be learned from the beginning. many amateur learn the wrong technique without proper training, it is very difficult to correct later on.
"on training young shuttlers:
"many parent are too impatient, they want their children to play many tournaments from very young. this is ineffective. before 16 yrs old, i believe fundamentals should be stressed. the focus should be strength and agility / flexibility."