Quercetin is a dietary supplement that has been touted for its antioxidant and anti-inflammatory powers. It's popular with some cancer patients and athletes and is found in FRS Energy, the sports drink promoted by cyclist Lance Armstrong. But a new study shows that it doesn't improve athletic performance.

Researchers funded by the Coca-Cola Co. tested the supplement in 30 recreational cyclists. Half received 1 gram a day of quercetin in a sports drink while the others received a drink that did not contain the substance. The men's performance on a maximum-effort cycling test was recorded at the start of the study and again after using the sports drink for seven to 16 days. There was no difference in the performance in the two groups in several measures, including peak oxygen consumption, metabolic changes and strength loss following the test. The study was published online this week in the Journal of Applied Physiology.

Quercetin is found naturally in the skins of fruits, leafy vegetables, berries, black tea and red wine. Lab tests in mice have demonstrated a positive effect on running endurance while studies in humans have been mixed.

The results were disappointing, said the lead author of the paper, Kirk Cureton, a kinesiologist at the University of Georgia in Athens. "Our hypothesis, based on previous studies in mice, was that we would see positive effects. But our findings are important because they suggest that results from the animal studies shouldn't be generalized to humans," Cureton said in a news release.

-- Shari Roan

Photo credit: Genero Molina  /  Los Angeles Times

Bicycling in Los Angeles is an intimidating prospect, what with traffic, cars and traffic. Did we mention traffic?

But riding a bike in L.A. can be fun, enjoyable and healthy, and you don't have to go from being a non-cyclist one day to being an uber-cyclist the next. Don't believe us? Take a gander at "The Bicycle Lifestyle Guide," a new booklet put out by Cyclists Inciting Change thru Live Exchange, an L.A.-based nonprofit group that promotes cycling as a healthy, practical and environmentally friendly way to get around town.

The booklet includes information on the positive aspects of cycling, plus essential gear (baskets, messenger bags, helmets) and how to gradually incorporate the activity into your life. One suggestion is to draw a 1- or 2-mile radius around your home and pinpoint a few rideable locations, such as markets and cafes, then gradually add more spots each month.

Sound really basic? Good. It's supposed to.

"We're coming from the viewpoint of the non-cycling public," said Liz Elliott, C.I.C.L.E.'s executive director. "Those of us who have cycled for a while can forget what it's like to be a new cyclist. But this will show people that they can have the same lifestyle and incorporate it bit by bit."

By not taking an all-or-nothing approach and focusing on the fun and green aspects of cycling, she hopes people will find riding enjoyable. The 30-page color booklet is available online, and hard copies are often handed out at C.I.C.L.E.-sponsored events (a donation is requested).

For those who want to take things a little further, C.I.C.L.E. also offers cycling classes.

So continue to watch the Tour de France, but don't succumb to pressure to bike the Alps. Or climb La Cienega. Said Elliott, "Even riding once a month is a noble effort."

-- Jeannine Stein

Photo credit: Kevin Ellis / AP

Roy M. Wallack and at least one special guest will be here at noon Pacific time to share bicycle training tips for riders who would like to tackle an endurance ride. Roy, the Health section's sports-fitness gear columnist and author of "Bike for Life: How to Ride to 100," has completed some of the world's toughest cycling and multi-sport events, including the Eco-Challenge, the 750-mile Paris-Brest-Paris randonnee and Costa Rica's 250-mile La Ruta de los Conquistadores.

Whether you are interested in preparing for the 50-mile Rosarito-to-Ensenada Fun Ride on Sept. 27 or want to push yourself to the limit in a double century, Roy and friends will be here to help.   

*Headline edited after chat to indicate that a replay of the chat is available (Click below to read).    

Every other week, Roy M. Wallack, our resident gearhead, shares his expertise with reviews of all sorts of fitness and athletic products. Because Roy is an avid outdoorsman and user of outdoor products, his Gear column is a great resource for people who can't always try before they buy.

Follow the links to read his latest column on more comfortable road bicycles or for an archive of reviews over the last year.

And then come back to this space this Thursday at noon (Pacific time) to chat with Roy about using some of the equipment: training for upcoming endurance bike events. Follow link for more on the chat subject matter. 

In rare bipartisan agreement, both Democrats and Republicans will have free bikes available for temporary use during their conventions, the Democrats in Denver from Aug. 25-28, and the Republicans in Minneapolis-St. Paul from Sept. 1-4. And you don't have to be a delegate, a pol or a nominee to use them. Anyone 18 and over can hop on and start pedaling. The bikes will be supplied through a partnership with Humana, a health benefits organization, and Bikes Belong, a cycling advocacy group.

If you'll be in Denver or Minneapolis-St. Paul for the conventions, the program will have 7 bike stations in each city. Get on one, go where you're going, and bring it back to one of the stations.

If they ride as much as organizers hope, cyclists could reduce the national carbon footprint by 4.4 tons by riding instead of driving. What's more, fat cats and others could collectively burn 200,000 calories.

The bike-sharing program, called Freewheelin, is the largest to date in this country. But many European cities, including Paris,  Berlin and Rome, have been putting out communal bikes for some time. Organizers are hoping that politically connected movers and shakers at the conventions will bring home the idea of sharing bikes to improve community health, cut down on traffic and reduce pollution.

-- Susan Brink

Photo: Matthew Staver. Bikes awaiting Democratic conventioneers in a Denver warehouse.

Let's assume you blew off your summer bicycling plans and are woefully out of shape. Don't worry. It’s never too late to start training in Southern California. And late August is the perfect time to get going, because the fall calendar is jammed with challenging events (see below). The question: What is the best way to prepare? Join us for an online chat a week from today, Aug. 28 at noon, when we'll talk about that. Bring your questions and advice too.

Common cycling wisdom gives us the “70% Rule" -- that if you can train yourself to ride 70% of your targeted one-day distance, then you will be able to go all the way on event day. Another strategy is to replicate the terrain of the event. If it's hilly, for example, then ride hills.

For instance, to prepare for the La Ruta de los Conquistadores -- a four-day crossing of Costa Rica from Pacific to Atlantic oceans that includes 35,000 feet of climbing -- I would ride from Sunset Boulevard to the Parker Mesa Overlook in Topanga State Park, a 45-minute granny-gear sweat-fest, four or five times on a Saturday to get my legs ready.

“But that’s just the start,” says Rich “The Reverend” White, a Big Bear tour guide and trainer who has completed La Ruta and the epic eight-day, 400-mile TransAlp Challenge through Germany, Austria, Switzerland and Italy. “Remember three things: eating, resting and hydration. Don’t do any one of those, and you are doomed.”

Notice that the Rev didn’t say anything about interval training or hills or cadence. Confused? Well, we hope to cut to the chase.

Here are some of the upcoming rides we will focus on:

FOR BEGINNERS:

Sept. 20-21 Bike MS Southern California. From Camarillo to Santa Barbara, includes 30-, 75- and 100-mile rides.

Sept. 27 The 50-mile Rosarito-to-Ensenada Fun Ride. The final running of this famous 30-year ride, a party-on-wheels that's flat except for an 800-foot hill climb at the halfway point.

FOR ENTHUSIASTS:

Nov. 15 Solvang’s Finest Century. A lightly trafficked back-road course through the verdant rolling hills of the inland Central Coast. 

FOR ENTHUSIASTS (WITH VACATION TIME):

Sept. 20-27 The California Coast Classic Bike Tour. This 500-mile, eight-day tour along Highway 1 from San Francisco to L.A. includes the coastal views, wineries and forests.

FOR ENDURANCE EXPERTS:

Sept. 27 Tour of Two Forests Double Century Poker Run. A
199-mile loop through Los Angeles, Ventura and Kern counties, from Santa Clarita to Ojai, then up to Pine Mountain to Lebec and back.

Oct. 25 Death Valley Century and Double Century.

Nov. 5-8 Baja Epic.  Starting from Rosarito Beach, this mountain bike race will cover 250 to 300 miles of singletrack and dirt roads in northern Baja California, including parts of the Baja 1000 auto and motorcycle race.

Nov. 12-15 La Ruta de los Conquistadores. This legendary off-road ride traverses Costa Rica from Pacific to Atlantic oceans, crossing sweltering tropical rain forest, freezing 12,000-foot mountains, and breezy Caribbean beaches.

-- Roy M. Wallack

Irvine-based Roy M. Wallack writes the every-other week Gear column for The Times' Health section. Reach him at roywallack@aol.com

Photo: Anacleto Rapping / Los Angeles Times