ROME, July 28, 2009 (AFP) - World swimming's executive body confirmed on Tuesday they will ban the high-tech bodysuits that have turned the record-book upside down, but said the change won't come until next April or May.

The FINA Bureau confirmed an overwhelming vote by the FINA Congress last week to ban the bodysuits made of polyurethane and other polymers that critics say offer unacceptable performance-enhancing properties.

The ban was originally projected to come into effect on January 1 of next year. But FINA executive director Cornel Marculescu said that the exact date of the implementation was not yet certain, although he vowed it would be "without question no later than April or May."

The delay raised a red flag for Bob Bowman, coach of US star Michael Phelps and head coach of the US World Championship team.

"I want swimming to go back to racing. This move to April is unacceptable," Bowman said. "It has to be January 1. If not, you know, next Monday.

"You can't trust what they say. It might be never."

The rules come too late to prevent a world record binge at the 2009 World Championships, where 15 world records fell in the first three days of competition.

That included Paul Biedermann's victory over Phelps in the 200m freestyle, in which the German eclipsed Phelps's world record.

Bowman said he would go so far as to advise Phelps to forego FINA-organized international competition, until the rule changes are in effect.

"My recommendation to him is not to swim interenationally until this is resolved," Bowman said.

Marculescu said the FINA Bureau had adopted by-laws focusing on the material and shape of suits, and on tests that they must meet to win FINA approval.

All competition suits must be made of "textiles," and FINA will release its exact definition of "textile" no later than September 30, to give manufacturers a chance to get to work on new suits.

Men's suits shall not extend above the navel nor below the knee, while for women suits shall not cover the neck or extend over the shoulder nor below the knee.

Nor can suits have zippers, as many of the current skin-tight creations require.

Rules will remain stating that swimmers cannot wear two suits at once, nor can they add tape to suits or modify them in any way.

FINA will limit its testing of suits to parameters that can be precisely measured and they will have to meet guidelines on thickness of material, buoyancy and permeability.

Marculescu said the new rules won't mark an end to advances in swimsuit technology, as the FINA Bureau will continue to reevaluate the rules based on input from a scientific committee.

The latest wave of technological advance was launched in 2008 with Speedo's LZR Racer, designed with the help of NASA.

Now the LZR is a dinosaur compared to polyurethane marvels from Jaked, Arena and other manufacturers.

As FINA dithered over the issue this year, personal best times dropped by astonishing seconds, records toppled and swimmers have had to wrestle with whether to seek out a competitive edge in a suit made by a rival sponsor.

The confusion over what is and isn't allowed has also seen swimmers subjected to suit inspections prior to races and seen some apparent world records denied because the suit worn hadn't been approved.