SPRINGFIELD, Mass. (AP) _ Machismo and a curriculum that aims to harden police officers to the stresses of their jobs may have been behind last month's outbreak of illness among recruits at an academy for local police forces.

Sixteen recruits out of a class of 50 were hospitalized for exhaustion and dehydration. Some needed kidney dialysis, and two remained hospitalized Saturday, including one who had to have a liver transplant and remained in a coma in critical condition.

The state attorney general's office is investigating. Two state troopers who were running physical and stress training for the class deny mistreating the recruits but have been temporarily reassigned at their own request.

''We categorically deny that we did anything that was not part of the regular training regimen, and believe that we will be vindicated by any objective investigation,'' the troopers, Blake Gilmore and John Richardson, said in a statement.

Doctors said the recruits suffered kidney failure and other problems because of too much exercise and too little water.

One recruit who dropped out of the program said they were given only a small amount of water. Some officials theorized that machismo may have kept cadets from asking for more.

''When you want to be a police officer, you've got a lot of pride,'' said Pittsfield Chief William M. Dermody. ''I wouldn't go to the bubbler first, either.''

Gary Egan, executive director of the group that runs the state's police academies, said last week, ''We have no one to date who was denied permission to have water on request.''

According to reports pieced together from recruits and police chiefs, on the first day of class, Sept. 19, there were two breaks for water in the morning at which the cadets were required to stand in line and fill paper cups from a fountain.

Some chiefs said they spoke about the academy off the record, saying they feared state trooper instructors would take revenge on their cadets. There has traditionally been tension between state and local police in Massachusetts.

''It's a conspiracy of silence,'' said one of the nearly dozen chiefs interviewed. ''I've got to send cadets down there and the troopers will get 'em.''

''We don't buy that kind of excuse,'' Egan said about chiefs who would talk only off the record. He is executive director of the Criminal Justice Training Council, a group of 23 law enforcement officials that runs the police academies.

The ailments that struck the cadets might still be secret if not for an anonymous caller who told The Associated Press on Sept. 22 to check on cadets in local hospitals and then hung up.

Pittsfield Mayor Anne Wojtkowsi said she is seeking national attention to the case so that there is ''no way the state can cover up this thing.''

The academy, one of five in the state, opened in 1984 to provide training for officers in the 74 towns and cities of western Massachusetts.

The outbreak of illness was not the first time trouble has been alleged at the academy. In previous years, one cadet claimed he was hit with a club, another said she was taunted while her head was shaved and another said he was forced to do pushups with a bucket on his head.

A member of the Massachusetts Commission Against Discrimination looked into the academy four years ago, following discrimination claims by two minority women.

Commissioner Frederick Hurst said the women told the truth about head shaving, humiliation and overexertion, but he denied they were singled out for punishment.

Michael Purcell dropped out of the academy and quit the Northampton police force after watching Timothy Shepard collapse from heat stroke Sept. 19.

Purcell claimed troopers pushed cadets to the limits of their endurance with pushups and laps and allowed them only a few small cups of water until Shepard collapsed.

Shepard, 25, of Pittsfield, underwent a liver transplant Tuesday at a Pittsburgh hospital and remained in a coma Saturday.

According to the chiefs and recruits, the cadets got an extended water break after Shepard collapsed and was taken to a hospital. But others who faltered were required to do more exercises, they said.

The Criminal Justice council's manual on stress training recommends that troopers verbally abuse cadets for performance failures and shout confusing orders.

''The cadets have to learn to control themselves and their emotions so they can handle the street,'' said Judy Crossen, director of training for the state's five regional police academies.

Barbara Kopans, assistant secretary of public safety, said the aim of the program was to condition recruits against overreacting.

''If they are eventually assigned to a riot situation, we don't want them to overreact if someone is throwing rocks at them,'' she said. ''We want them to learn not to let their anger carry them away.''

''We are not doing it just to be mean. There is a reason for it,'' she said.

She said the physical training of the Agawam class has been put on hold during the investigation, but the recruits are still subject to verbal punishment and induced stress.

Some military trainers say abuse is counterproductive. ''There was a time when Army training was abusive,'' said Lt. Col. Gregory Rixon, a Pentagon spokesman. ''That's gone by the wayside. There's no use in calling somebody 'maggot' or 'meathead.'''

Some of the western Massachusetts police chiefs who voted unanimously in 1984 to support the academy's tough training say they now wonder about the wisdom of the program.

''We don't need Marine Corps recruits,'' said one chief. ''We need compassionate human beings trained to handle situations, and you don't get that with a lot of Gestapo storm troopers humiliating people.''