Sarah Leaf

Sarah Leaf (Courtesy Shape-Up Fitness and Spa / September 17, 2012)

Friends and colleagues of a Corona del Mar cyclist killed Friday morning described her as social, energetic and passionate about her work in helping people lose weight through personalized health programs.

"I loved how she was persistent and gentle," Robert Burns, owner of Shape-Up Fitness and Spa, said of Sarah Leaf.

Leaf, 29, had provided nutritional consultations since 2009.

Over the years, Burns said, Leaf worked with more than 200 clients and frequently dispensed quick health tips to club members.

"She was relentless … but if she wasn't so upbeat and sincere, she wouldn't have gotten away with it," he said.

Nicole Bentley, Leaf's longtime friend and roommate, remembered her as a go-getter who made plans, then stuck to them.

"She wanted to go to California; she went to California. She wanted to be a nutritionist, and she just did it," Bentley said. "She did all that on her own."

Leaf, a Mesa, Ariz., native, moved with Bentley to Orange County shortly after both of them graduated from the University of Arizona. Leaf majored in psychology and was a member of the Alpha Phi sorority, according to Bentley.

"She really made people's lives better," Bentley said, "not only through her work, but she was so joyful all the time."

That sincerity and holistic commitment to health in her own life made Leaf a particularly effective motivator, said Mari Frome, a friend and former client.

"She obviously practiced what she preached, as far as being healthy — mentally and physically," said Frome, who frequently worked out with Leaf.

Frome said she and Leaf had just parted ways after a bike ride along Coast Highway when Leaf was struck and run over by a truck near East Coast Highway and Bayside Drive. Frome said the pair had planned to meet up again for a noon boxing class.

When a mutual friend at Shape-Up called to say that Leaf hadn't arrived back at the club as expected, Frome said she "got right in the car, figuring [I] would find her with skinned knees."

Instead, Frome said, she came upon the site of the crash, where she stopped and spoke to officers.

Newport Beach Police Department spokeswoman Kathy Lowe said Monday that the 53-year-old male driver remained at the site of the accident and has not been cited or arrested.

Leaf died at the scene about 10:40 a.m. Friday. An investigation into the collision is ongoing, Lowe said.

Ultimately, Frome said she admired Leaf's outlook.

"On our ride that day, as we were looking at the ocean, [we were] just talking about how thankful we are about where we live," Frome said. "She was just always looking at life in a positive way."

Leaf is survived by her parents, older brother and younger half-brother.

Burns said Shape-Up will hold a memorial for Leaf on Saturday.

A Ghost Bike-style memorial, with a white bike and replete with flowers, has been set up for her near East Coast Highway and Bayside.

jill.cowan@latimes.com

Twitter: @jillcowan