"I have weak hearing and poor sight. I have problems all over my body," she said. "But I am still young in spirit."
Shigemoto is one of a troupe of elderly actors -- average age 74 -- under the tutelage of world-renowned director Yukio Ninagawa.
"I have already reached the afternoon of my life, but it's wonderful to spend my last days with the company," Shigemoto told AFP at a recent rehearsal in Saitama, near Tokyo. "I really like acting. This is what I live for."
Ninagawa, whose directorial prowess has taken him to some of the world's finest theatres, founded the Saitama Gold Theatre seven years ago and made a rule of auditioning only people aged over 55. Acting experience is not required.
He said he began the "experiment" to create a new style of theatre that would see older people take roles not usually open to them -- like the leads in Shakespeare's Romeo and Juliet.
"To ordinary theatre people, it is an unconventional group," said Ninagawa, himself 77 years old.
For him, the company is the antithesis of the visually-arresting and vividly-staged works that have given him a global reputation, in which young actors take on huge roles.
The elderly players he directs have proved something of a revelation to Ninagawa, who says they are capable of bringing a huge range of emotions to bear, sometimes simply by nature of their deeper wrinkles or their sagging cheeks.
"You can't obtain such expressions before you are 60," the veteran director said. "It is meaningless for youngsters to pretend to have that."
"With this company, I can feel a sense of excitement," Ninagawa told AFP. "Without this I'm afraid I could be stuck where I am."
After five successful productions in Japan, Ninagawa is taking his troupe abroad, with Paris as the first destination and hopes for other countries in Asia in the future.
The Maison de la culture du Japon a Paris will play host to the avant-garde "Ravens, we shall load bullets!" from May 30 to June 1, a play he first directed in the 1970s which tells the story of the sometimes violent struggle in Japan against societal repression in the aftermath of World War II.
In the play by Japanese author Kunio Shimizu, old ladies occupy a courtroom where they sentence a judge, a prosecutor and their grandsons to death before a spectacular clash with riot police brings the whole protest to a brutal climax.
Ninagawa said the play that he presents to Parisian audiences, which will be in Japanese with French surtitles, will be a challenge to them.
"I don't want to produce a carbon-copy of a European drama," he said, adding that he has no plan to change his style of direction or the staging from that he has used in Japan.
"I don't expect the whole of the audience will appreciate it," he said. "I only hope that people in Paris will say: 'Hey, grandmas and grandpas have come from the Far East as a group and did what they called drama, but it's inspiring'."
The company is also his attempt to cast a spotlight on the issue of ageing in Japan, where people aged 65 or over make up around a quarter of the 128 million-strong population.
The figure, already one of the highest proportions in the world, is expected to rise to around 40 percent over coming decades, putting a strain on health and welfare services as the wages of relatively few young people need to be spread ever further.
"The ageing issue is one of the most pressing problems Japan is facing," said Ninagawa.
"With this company I can examine this issue and can highlight the difficulties with the present situation using this play."
As well as providing social commentary, the company is also a font of inspiration and fulfillment for participants -- a key challenge for a greying society.
Actor Kiyoshi Takahashi, 85, said the stage had given him a new zest for life.
"Drama makes me vigorous. I'm too busy to get senile," he said. "I still feel as if I were 20 years old and now my dream is to become a good actor."
Ninagawa, who underwent a heart operation in January, says although he sometimes forgets his own age, working with a group of older actors feels very appropriate.
"As you get older, you fluff lines and sometimes forget about your entrances and exits," he said.
"But acting gives everyone vigour and is proof that people can grow at any time in their lives."
"This company gives me the energy to keep going and hang on in there."