Armstrong hopped on his bike Saturday morning in the town of Waterloo, Ontario – along with 40 other local residents – for a 117-kilometer "Ride With Lance" event. Donations were to raise money for cancer treatment for two nearby hospitals – Grand River Hospital in Kitchener and Sunnybrook Hospital in Toronto.
The couple – who have remained mum about their relationship – managed to have a romantic yet rugged mini-vacation before the race. They braved mosquito season for several days in Muskoka, a northern Ontario summer vacation enclave where Hudson's mother, Goldie Hawn, has a cabin.
Then it was back to the big city. On Friday, Hudson took 4-year-old son Ryder out for lunch and ice cream in the trendy Toronto Yorkville shopping district and was also spotted with Armstrong's kids (Luke, 8, and 6-year-old twin girls Grace and Isabelle) as he busied himself with pre-race festivities.
That night, Hudson and Armstrong were spotted hugging in the lobby of their midtown hotel in Toronto. "He was laughing and she was laughing and they put their arms around each other," says one observer of the embrace. "It was sweet."
After Saturday's race, the actress joined Armstrong for a gala dinner at a country estate (where one thoughtful fellow guest presented them with cans of the insect repellant OFF!) and the couple happily posed for photos and chatted with the other participants about their kids and upcoming Father's Day.
Asked if his kids like to ride bikes, Armstrong said, "They play flag football and do gymnastics," says one guest.
"I was pretty starstruck," says Tom Wideman, 47, a local businessman and one of the riders who rode up front with Armstrong during the bike ride. Wideman raised $42,000 for the fund-raising event and says the "down-to-earth, genuine" qualities of celebrities like Armstrong and Hudson is inspiring. "As a cancer survivor, Lance is very committed to take on the cause."