The wheelchair sprinter from Nanoose Bay, B.C., discovered via wind tunnel testing in Ottawa earlier this year that covering her head made her more aerodynamic in her chair.
The new headgear paid off. Stilwell defended her Paralympic gold medal in the women's 200 metres in 33.80 seconds Saturday. She shattered her Games record by over two seconds. The 38-year-old will go for a double dose of gold when she races the 100 metres Wednesday.
Her eyes shrouded behind dark glasses and her hair pulled back in a ponytail under the cap, Stilwell edged Belgium's Marieke Vervoort by three tenths of a second at Olympic Stadium.
"Even if it's just hundredths of a second it saves me, honestly I should have had it in a bun tucked in, but I wanted people to know that I actually have hair," an elated Stilwell said following her race.
Stilwell is quadriplegic and races in the T52 classification. Wearing a cap in a race for the first time in her career was just one item in the life blitz Stilwell conducted in her bid to stand atop the Paralympic podium again.
Her diet, race chair setup, clothing and training location were all overhauled.
"Every little detail, we've worked at it," Stilwell said. "It's an incredible training plan that Peter (Lawless) my coach and I came up with. Obviously it worked."
Canada had eight medals, including three gold, after three days of Paralympic competition in London.
Valerie Grand'Maison of Fleurimont, Que., earned a silver medal in women's 50-metre freestyle Saturday. The visually impaired swimmer won three gold medals at the 2008 Paralympics in Beijing. Grand'Maison will also race the 100-metre freestyle, 200-metre individual medley and 100-metre breaststroke in London.
Canada's objective in London is to finish top eight in the gold-medal count. With three, the Canadian team was tied for 10th with Germany, Cuba and Iran. China led all countries with 19 gold.
Stilwell, her husband Mark and their 11-year-old son Kai moved to Australia for three months over the winter so Stilwell could get quality training in prior to London. Mark quit his job in computer programming so he could home-school Kai, who is autistic, while his wife trained in Australia.
"It was a huge sacrifice we've all made to make it happen," she said.
Stilwell and her husband planned a quiet, belated celebration of their 15th wedding anniversary, which was Friday, following her race. No champagne, just water with lemon.
"I'm going to go spend the evening with my family," she said. "I'm going to stay out of the village tonight and have some relaxing time, come back in around noon tomorrow and refocus and get set for Wednesday night."
A clan of over 20 supporters in red T-shirts with her nickname "Mikey Stilwell" are in London. Stilwell became tearful while relating that her brother Ken from Winnipeg was in Olympic Stadium to see her race for the first time.
At age 17, she fell backwards onto basement stairs while riding piggy-back on a friend. Her neck struck the stairs, rendering her a quadriplegic. Stilwell won basketball gold in Sydney in 2000 and then switched to wheelchair racing.
Setting records in the 100, 200 and 400 metres already this calendar year made Stilwell appear untouchable as London approached. She had dominated American rivals Kerry Morgan and Cassie Mitchell at a meet in Windsor, Ont., in July.
But Stilwell was unsure about Vervoort, whom she hadn't previously raced. The Belgian was re-classified from a T54 - which has more arm function - to a T52 in May.
Stilwell peaked over her right shoulder at Vervoort over the final metres. The Canadian pumped her fist after crossing the line. The glance might have cost Stilwell a chance at breaking her own world record of 33.58, but she feels she has peace of mind now.
"I can focus on the 100 and be a little bit more confident knowing where she's at," Stilwell explained. "Really, it's just not knowing, when you're at a huge Games like this and you've never seen a competitor and you don't know what their capable of, it does give you a little bit of something in your head.
"All it takes is one slip-up. You've got to be pretty focused to bring it on the day."
In other track finals, Braeden Dolfo of Langley, B.C., was seventh in the men's T11-13 100 metres, which is visually impaired.
In swim finals, Katarina Roxon of Corner Brook, N.L., finished fifth, Sarah Mehain of Vernon, B.C., placed seventh and Calgary's Brianna Nelson eighth in women's 100-metre breastroke for swimmers with a physical disability. Amber Thomas of Drayton Valley was sixth in 50-metre freestyle.
Marie-Claude Molnar of Lemoyne, Que., was 10th in the women's 500-metre time trial for track cyclists with physical impairment. Daniel Chalifour of Lac-des-ecorces, Que., placed eighth in the men's time trial for the visually impaired.
Lauren Barwick of Aldergrove, B.C., and Off To Paris were sixth in Para-dressage.
The men's wheelchair basketball team remained unbeaten in three games after downing Poland 83-65. The Canadian women were 1-1 following a 57-50 victory over Australia.
The women's goalball team fell 2-1 to Sweden, but the men's team fought back from a three-goal deficit to beat South Korea 5-4.