CREDIT: Bruno Schlumberger, The Ottawa Citizen Natasha Paremski says she prefers to have weeks to prepare for concerts, but took the gig with the NACO after being called at the last minute. For Richard Todd's review of last night's concert, go to ottawacitizen.com

CREDIT: Bruno Schlumberger, The Ottawa Citizen Natasha Paremski is known for her percussive, energetic playing, which had members of the NAC Orchestra applauding her after yesterday's rehearsal.

When Russian pianist Natasha Paremski plays the softer passages of Tchai-kovsky's Piano Concerto No. 1 tonight, you may hear a faint rumbling coming from the stage at Southam Hall.

That would be Ms. Paremski's stomach.

She likes to hit the stage hungry. So hungry that breakfast is a distant memory. Fasting is her pre-concert ritual.

"I've got this really weird thing," said Ms. Paremski. "I starve myself so I'll be like a starving musician and I'll play better. That seems to work. Plus, Tchaikovsky was such an unhappy man. How can I be happy and well-fed and play well? After the concert, I'll be really starving and skinny," she laughed.

Ms. Paremski is only 20, but already has a well-earned reputation for pinch-hitting when a scheduled performer is sidelined by illness. On Monday night, she got a call from her manager. He asked her to substitute for the ailing Boris Berezovsky at the National Arts Centre's Bostonian Bravo Series concerts last night and tonight.

"I told him, I'll have to call you back in half an hour. I haven't played it for about a year and a half, so I'll run through it and see how it feels. It felt great, and here I am."

Ordinarily, Ms. Paremski prepares for a concert with painstaking thoroughness.

"I probably would have given myself two or three weeks, not that I need two or three weeks to bring it back. That's usually how I do things."

"This time it was condensed into five or six hours," she said. "But it was fun, it was a challenge, and I'm really glad that I took it up."

Last summer, she performed Rachmaninov's Second Concerto as a last-minute replacement for the opening night of the Caramoor Festival in New York. Four days later, she played it again at the Bravo! Vail Valley Festival in Colorado.

"That time, my manager called and it was, 'OK, Rach Two in Vail, Colorado. Can you do it again? I said, 'Yeah, sure. I just played it.'"

Ms. Paremski spoke to a reporter yesterday morning after rehearsing the Tchaikovsky concerto with the NAC Orchestra and Norwegian conductor Arild Remmereit.

At the run through, she played the concerto's fast passages so forcefully that it turned her Steinway into a troika thundering through the Russian countryside. When she finished the 30-minute piece, some players in the string section stamped their feet in approval. Others applauded heartily.

Moments later, Ms. Paremski replayed a tricky ensemble passage after conferring with the conductor. Then she turned to the orchestra, clenched her fists and said "Yesss!" in triumph.

"The first time I play through with an orchestra, I really listen to what they're doing and their sound and balance. There are places where the piano melody doubles the flute, and the oboe melody and the clarinet melody. I really have to listen for them. Sometimes they can't hear me at all because the piano lid is out and they are sitting way far back and you have strings in the middle and the strings are playing. So it's really my job to listen to them and kind of make contact. That's what I do in first rehearsal.

"The orchestra is so responsive, it's so easy to play with them. You kind of feed off each other's energy. It's always great when you get along with an orchestra and you know they're there and we're all listening and playing beautiful music."

She also connected with Mr. Remmereit, who opens tonight's program with selections from Tchaikovsky's opera Eugene Onegin. The concert concludes with the composer's seldom-heard Symphony No. 3.

"He's great, and very energetic. I think that's essential for performing regardless of age. I'm young, yeah, but I hope this energy is never going to leave me. I really identify with the conductor's energy. It means we're both on the same page."

The NAC Orchestra is so well-seasoned that a last-minute substitution is no biggie, as Ms. Paremski's generation might put it. On one memorable occasion, conductor Trevor Pinnock became ill and had to cancel a concert with cellist Yo-Yo Ma. Toronto conductor Victor Feldbrill flew in and walked out on stage with no rehearsal. Mr. Ma and the orchestra performed brilliantly.

The Tchaikovsky concerto resonates with Ms. Paremski, as might be expected.

"I really relate to it, I feel it's part of my soul. It's Russian music and I was born in Russia. I just find it to be a really beautiful piece. It's so great to just flow with the music and play it.

"I was eight when my family came to America. I was playing loosely at two and studying at four. The piano has always been a part of my life, sort of like an extra limb."

The concerts mark Ms. Paremski's Canadian debut. She has performed with the San Francisco Symphony, the Los Angeles Philharmonic, and the Royal Scottish National Orchestra. As well, she has given concerts in London, Paris and Zurich.

When she received the call to come to Ottawa, Ms. Paremski was busy mastering John Corigliano's piano concerto for upcoming concerts in Florida and California. "I thought, 'What the heck. I can take a few days off.'"

She has a percussive style, and her technique is so dazzling that Oscar Peterson must be smiling down from heaven.

When she plays the Tchaikovsky concerto tonight, even on an empty stomach, concert-goers should expect fireworks like Canada Day.