Singapore's top female sprinter Shanti Pereira says she is feeling "nervous, but good" ahead of this morning's 200 metres heats at the Olympics.

The 24-year-old, who owns the national records for the 100m (11.58 seconds) and 200m (23.60 sec), will take part only in the latter event at the Tokyo Games.

She will race in the fifth of seven heats - alongside 100m bronze medallist Shericka Jackson - at 11.02am (10.02am Singapore time), and will be the first woman to represent the Republic in the sprints at the Games in 65 years.

The last Singaporean women sprinters were Mary Klass (100m and 200m) and Janet Jesudason (100m) at the Melbourne Olympics in 1956.

Pereira arrived in Tokyo on July 25 and has been acclimatising to the hot, dry Japanese summer, managing six sessions on the training track.

"We've just been fine-tuning some stuff," she told The Straits Times of the work she and coach Luis Cunha have done in Japan.

"The training itself is similar to what I did in Singapore the (previous) couple of weeks. We focused on quality and not as many sets… High intensity, high quality."

Asked how she felt after a week in Tokyo, she said: "Good! Nervous, but good."

She visited the 68,000-capacity Tokyo Olympic Stadium - which sadly will be devoid of fans because of the Covid-19 pandemic - the first day it was open to athletes last Wednesday, and was struck by how much it felt like home.

"I had the feels," she said, "and was like, 'Whoa… It looks and feels so much like the (Singapore) Sports Hub...

"Everyone there that day was very excited, with the Olympic rings on the track and everything. The atmosphere was very nice."

Pereira said she and Cunha, a Portuguese who raced at the 1988, 1992 and 1996 Olympics, walked an entire round of the track "to take it all in". Here, she has also been quietly absorbing lessons from some of the world's best.

She has come across Jamaican stars Shelly-Ann Fraser-Pryce and Elaine Thompson-Herah, who retained her 100m gold on Saturday night, and American Allyson Felix several times on the track and in dining halls.

But she is less star-struck these days, and it was "not so much of a freak out", as she had also encountered such names at the World Championships in Beijing in 2015 and Doha in 2019.

Still, she added: "It's really nice to be able to watch their warm-up routines... because there are so many Olympic and world champions in one place, it's good for me to see and maybe pick up one or two (lessons) to better myself too.

"But, at the same time, I don't want to get distracted because I'm doing my own training so I mostly focus on myself (at the track)."

Before she left Singapore, Pereira, who is in Tokyo on a universality place, told ST her goal at the Olympics was to take another step forward in her "long-term" plan with Cunha - who began coaching her in January last year - to lower both her 100m and 200m national records.

She reiterated this and said: "I want a good time, a personal best or something (near to it) that is good. But the fact I am here, I am already thankful. I am not going into (the heats) with too much expectation, and I want to focus on enjoying my race."