Centennial Beach transforms from a neighborhood swimming hole into a USA Triathlon-sanctioned racecourse Sunday, Aug. 2, when hundreds of athletes dive into the historic quarry pool for the 18th Naperville Sprint Triathlon.

The race starts at 7 a.m. at 500 W. Jackson Ave. and runs through approximately noon. The sprint course covers a 375-meter swim in the beach's open-water pool, a 22K bike ride through roads surrounding downtown, and a 5K run.

A kids triathlon (175-meter swim, 11K bike, 5K run) is open to athletes ages 7–15, and relay teams can split the sprint distance among members. Duathlon and aquabike options are also available.

Race organizers call it a starter-friendly course built for athletes of every ability level in the "safe surroundings of the Centennial Beach pool and park," according to the event's official website. All finishers receive a T-shirt, medal, and complimentary post-race food.

There is no race-day registration. Athletes who missed packet pickup at Naperville Running Company on Friday, July 31, and Saturday, Aug. 1, can grab bibs race morning between 5:30 and 6:30 a.m. at the transition area for an added fee.

Spectators can park at Naperville Central High School or in neighborhoods adjacent to Centennial Park.

The triathlon caps a fitness-packed weekend. On Saturday, Aug. 1, THRIVEFest brings live boxing, yoga, and barre sessions to Benedetti-Wehrli Stadium on the North Central College campus, 9 a.m. to 3 p.m. Admission is $10.

The following weekend, the 29th Annual Naperville Sunrise Rotary Ride on Sunday, Aug. 9, offers routes of 21, 41, and 62 miles starting from Trek Bicycles at 3416 S. Route 59. Stephanie Colbert Randall, the Rotary Club of Naperville Sunrise's secretary, told the Daily Herald on July 22 that the club donates more than $80,000 annually to local charities.

"It is a beautiful, scenic ride," Colbert Randall said. "We get a lot of compliments about our rest stops, which are spaced out about every 10 miles."

This week in Naperville sports

Saturday, Aug. 1 — THRIVEFest, Benedetti-Wehrli Stadium, 455 S. Brainard St., 9 a.m.–3 p.m. $10 admission.

Sunday, Aug. 2 — 18th Naperville Sprint Triathlon, Centennial Beach, 500 W. Jackson Ave., 7 a.m.–noon. No race-day registration. Spectator parking at Naperville Central High School.

Monday, Aug. 3 — Naperville Park District fall program registration opens at 8:30 a.m. for residents (nonresidents Thursday, Aug. 6).

Wednesday, Aug. 5 — IHSA football practice begins statewide, including Naperville North, Naperville Central, Neuqua Valley, and Metea Valley. Start date moved up five days after a 290–245 member-school vote in February.

Saturday, Aug. 8 — Junior Tour de Naperville, Wolf's Crossing Community Park, 3253 Wolf's Crossing Rd. Ages 3–5 at 9 a.m., ages 6–8 at 10 a.m., ages 9–12 at 11 a.m. Helmets required.

Saturday, Aug. 8 — Rescheduled Naperville Community Fireworks, Frontier Sports Complex, 3380 Cedar Glade Dr., 9:30 p.m. Free.

Sunday, Aug. 9 — 29th Annual Rotary Ride, Trek Bicycles, 3416 S. Route 59. Routes of 21, 41, and 62 miles. Start 6:30–10 a.m. $50 registration. Proceeds benefit Little Friends, Grow Wellness, and Naperville YMCA scholarships.

Monday, Aug. 10 — IHSA fall practice begins for cross country, golf, soccer, tennis, and volleyball at all four Naperville high schools.