Washington area rowers moved off the Potomac River yesterday and into the unlikely setting of the historic second-floor ballroom of the Potomac Boat Club to compete in a grueling five-mile dry land rowing event.

Sixteen rowers strapped their feet into one of six of the latest model ergometer machines designed to simulate the strength, power and cardiovascular properties of actual water rowing at the Washington's Birthday Ergometer Regatta.

The Concept II ergometer machines used were manufactured by 1972 Olympic oarsman Dick Dreissagacker and his brother Peter. They cost $595.

"One of the whole benefits of the machine is to make it like rowing," Bob Spousta, who won the men's open event, said. "Rowing hard and rowing long strokes is what it is all about."

Spousta, 33, is beginning his seventh year as the coach for the T.C. Williams High School crew team and rows 40 miles per day on an ergometer he keeps in his basement.

"At this point in the season, I just try to row a long ways," said Spousta, who estimated his pulse rate was above 175 beats per minute during the five-mile race which he covered in 7:54.3. Spousta said he will cut back on the ergometer as he gets more water time as the weather improves.

The ergometer helps rowers maintain and develop strength during the offseason and refines power techniques, Spousta said.

The machine is operated by pulling a wooden bar towards the chest while the feet push against a stationary platform which drives a sliding seat backward on a rail. The bar is attached by a chain to a bicycle wheel and a series of gears to adjust the resistance, and therefore the power that the athlete can generate.

The ergometer uses an odometer to measure the simulated distance traveled during each pull and a power meter to monitor the intensity of each stroke.

Charlie Butt, who coaches the Washington-Lee High School team, put five of his top prospects on the ergometer and was pleasantly suprised when Eric Jaer, a senior transfer student from Oslo, won the event despite no formal rowing background. Jaer's winning time was 9:15.4 and teammate Ralph Baird was second.

Baird said he prefers to be out in the water doing the strenuous work, rather than in the ergometer.

"When we're all out there working together, you can really feel the boat move," said Baird, 17, a senior. "You can feel yourself pulling and you know you are really going fast."