When John Allen Muhammad gets his daily allotment of one hour away from his tiny Prince William County jail cell, he spends it showering, walking for exercise or doing long sets of push-ups. John Lee Malvo is similarly confined in an adult Fairfax County cell -- a teenager who spends his days surrounded by thick concrete and steel.

Both are charged with capital murder as part of a terrorizing string of sniper slayings, and because of the violent and random nature of the shootings, Muhammad, 41, and Malvo, 17, are considered the highest security risk.

The pair who traveled the country and allegedly shot 21 strangers and killed 14 are among the highest-profile suspects ever held in Northern Virginia jails.

Their stay in solitary confinement, however, doesn't make them much different from other inmates who have been charged with capital crimes and are considered dangerous or in danger from others. They're locked in by themselves for most of the day, never have contact with fellow inmates and are monitored round-the-clock.

"We have had several people who have been charged with capital murder and could possibly be a security threat," said Col. Glendell Hill, superintendent of the Prince William Regional Adult Detention Center in Manassas. "They are treated the same way as Mr. Muhammad is being treated now. It's routine for us to house a person that's classified like Mr. Muhammad."

Routine means that Muhammad spends 23 hours a day in a 72-square-foot cell with a small opaque window -- alone but for reading materials and some court documents. There's no television on his block, and Hill said Muhammad reads occasionally and does regular exercises when he's allowed out of his cell for 60 minutes a day.

Muhammad eats his meals in the cell -- like all the other inmates in Prince William County -- and sticks to a vegetarian diet. Hill declined to comment on the specifics of the jail's menu but said it regularly accommodates vegetarians.

"He's been treated well by the jail," said Peter D. Greenspun, one of Muhammad's defense lawyers, addressing a news conference Wednesday.

Because Malvo is a juvenile, Fairfax County Sheriff Stan G. Barry declined to comment specifically on his confinement. But Barry said Malvo is held according to standard procedure for any high-risk juvenile housed at the Fairfax County Adult Detention Center.

Any inmate such as Malvo is held apart from others and can neither hear nor see them. The high-risk juvenile stays alone in a room -- 7 1/2 feet by 19 feet -- that would normally be used as a day room for inmates. Juveniles have a mattress for sleeping and a stainless-steel table and bench. At night, one of two overhead lights remains on.

Fairfax inmates are served a hot breakfast, typically waffles, scrambled eggs or oatmeal, sandwiches for lunch and a hot dinner, sheriff's officials said. They have access to paperback books that are brought around on a cart and can order their own directly from a publisher.

Inmates who are segregated from the general population exercise alone and can walk in the gymnasium or ride an exercise bike.

They have access to a telephone from about 8 a.m. to 11:30 p.m. and can meet with their attorneys in visiting rooms.

Malvo's lawyers have argued that he should be held with other juveniles, and they are expected to do so again today in Fairfax County. Prosecutors have argued that Malvo's attempt to escape from federal custody after his arrest Oct. 24 -- he climbed up through ceiling tiles when left alone in an interrogation room -- makes him more of a risk.

According to jail officials and sheriff's deputies, Muhammad has been acting like a military prisoner: He's respectful but almost completely silent. Hill said Muhammad will answer direct questions from jail guards when asked about his mental condition and his overall well-being.

"He hasn't given anyone any trouble that I know of," said Prince William County Sheriff E. Lee Stoffregen III. "There haven't been any problems. He'll respond to direct orders and directions with an affirmative or a negative, but that's about it."

Stoffregen said that when in the courthouse, Muhammad is treated differently from most suspected criminals because he presents a higher security risk than normal and is part of an extremely high-profile case.

It isn't the first high-profile case Prince William has had. Most comparisons are made to the Lorena Bobbitt trial, which introduced the county's judicial system to national and even international scrutiny. That trial led to many of the security plans the courthouse has in place today.

"But the Bobbitt case was more of a novelty trial, and it certainly was a new thing for us then," Stoffregen said. "This case is entirely different. This gentleman's actions affected a lot of people, and there are a lot of people who might want to harm him. That's a big concern for us, and we have to make sure everyone is safe."

That includes the judge, the court reporter, the defense attorneys and prosecutors, the sheriff's deputies and the gallery of spectators. In a recent trial, a defendant splashed Commonwealth's Attorney Paul B. Ebert with a cup of water in anger, and deputies want to guard against something worse.

When in court, Muhammad is surrounded by six deputies -- four more than usual -- with each deputy assigned to watch a different aspect of the courtroom. When he's moved from the jail to the courthouse holding cell, via a secure 100-yard tunnel, he's shackled and escorted by several deputies.

Although there is no camera in his cell, Muhammad is monitored on video the entire time he is in the courthouse.

Even the airspace over the courthouse is affected by Muhammad's appearances.

"We don't want helicopters flying overhead," Stoffregen said. "They can drown out the press conferences and, who knows, there could be a sniper inside. We don't want to take any chances."

The U.S. Marshals Service is also on call while Muhammad is in Prince William. The agency has played a large role in helping beef up security at the courthouse in the past few years. Stoffregen regularly consults with its experts and has implemented several security features as a result. Two years ago, he added metal detectors and an up-to-date alarm system.

"We're ready for anything," Stoffregen said. "But we don't anticipate having any problems."