Young children have been sent crying from running tracks thanks to a hardline rule bringing 7-year-old children in line with Olympic athletes.

The rules enforcing automatic disqualification for false starts resulted in young competitors being reduced to tears at the Colgate Games in Tauranga last weekend, spurring boos from some outraged spectators.

The rules have been described as too harsh for young children by some of New Zealand's top athletics coaches, with gold medallist triathlete Hamish Carter's former mentor calling for a law change.

Masterton 8-year-old Bella Milne was "devastated" and in tears after she was disqualified for a false start in the 60m sprint, her father Robert Milne said.

"She was just a bit unbalanced and was disqualified ... she had been pretty keen to run that race and it was absolutely gutting for her.

"It didn't make me angry, but it made me feel very sad for her. I think the rule is a bit too heavy-handed for the babies, shall we say."

Auckland man Gregory Strong was watching his grandchildren compete and was disgusted at the sight of several children being cut from races.

"A couple of them were crying ... and one girl was quite upset. The poor little kids were just distraught and there were a lot of boos from the grandstand."

Afterward, Mr Strong questioned officials about the rule.

National track and field coach Chris Palone said officials had brought in the rule, partly to prevent competitors making deliberate false starts to gain psychological edges over each other, after the athletics world championships in 2009.

"But whether that is appropriate for youth in New Zealand in any event is debatable," said Mr Palone, who has coached Carter.

"I do believe it's inappropriate at the level and that probably common sense should prevail and we can come up with an alternative bylaw in New Zealand."

Dunedin-based Brent Ward, who coached Olympian sprinter Chris Donaldson, said young children found it tough to hold themselves in a set position at the start line.

"At that age, they're often not strong enough ... so you're asking kids to do what some of the most mature and skilled athletes in the world can find it pretty difficult to do. It sure is an easy way to put them off the sport, rather than encourage them."

Tauranga Ramblers coach Malcolm Taylor said one little girl was left "crying her eyes out" when eliminated from one event but went on to win the 200m sprint after being consoled.

"They've got to be trained to listen to the gun. I'm sympathetic to them, but I think we were trying to be fair at Colgate and the rules had to be adhered to."

The Colgate Games was run by the New Zealand Children's Athletics Association (NZCAA). NZCAA vice-president Brian Curry said the rules, created by the International Association of Athletics Federations, were introduced in recent years. He could not say whether his association had been obliged to implement them.

The false start rule
* The rule was approved in 2009 and started on Jan 1, 2010.

* Any athlete who makes a false start is disqualified.

* It was started to prevent slower-starting sprinters from deliberately false starting.

* Jamaican sprinter Usain Bolt was disqualified from the final of the 100m at the world championships last year after he false started.