Pushy and abusive parents who are highly critical of their child's performance on the playing field are turning them off sport, according to a poll.
Youngsters as young as eight reported being told they are "too heavy", "lazy to run" or have made a "pathetic mistake" by over zealous mums and dads.
Some pupils said that their parents had sworn at them, while one admitted they were told "you're not good enough, you can't do it, you're worthless".
Nearly half of more than 1,000 eight to 16-year-olds questioned said the bad behaviour of their parents made them feel like they did not want to take part in sport.
The study, by Marylebone Cricket Club (MCC) and the Chance to Shine charity, also highlighted the bad behaviour of adults on the touchline.
One youngster said they had seen a parent who "swore at their kids and made them cry", another saw someone throw a coffee cup at an official, and a third child reported that a dad "hit the ref once for sending his kid off".
It was not all bad news though - the poll also found that 66.1% of children were happy when their parents were there to watch them, with 51.4% saying it made them feel proud.
Just over half said they thought winning meant the same amount to their parents as it did to them, while one in four said a win meant more to their parents and 22.9% said it meant more to them and their team-mates.
The poll questioned 1,002 eight to 16-year-olds who play sport between March 20th and 25th.