As a sport, running is about as cheap as it gets – all you need is a pair of sneakers.

But training for a triathlon, which includes swimming, cycling and running comes with a pretty hefty price tag.

“The cost to train for your first triathlon can be several thousand dollars,” says Martha Szufnarowski, the founder of TriLa Vie, a triathlon training program in Orange County, Calif.

From equipment costs and gym memberships to coaching and race entry fees, the cost to race quickly adds up for aspiring triathletes. On top of the costs, training requires a significant amount of time, up to 20 hours a week for an Olympic-standard triathlon, according to Jeff Booher,  founder of TriDot, which trains triathletes using patent-pending software.

Taking the cost and time commitment into account, it can start to seem like the sport is only for the wealthy. In fact, the average income of triathletes in the United States is well above the mean. A study conducted by USA Triathlon in early 2009 found that the average triathlete earns $126,000 per year – more than twice the median income in the U.S.   

Who Competes in Triathlons – and What They Spend

USA Triathlon’s study suggests that the majority of triathletes, in addition to being well paid, are also highly educated.

Nearly half of triathletes surveyed are white-collar workers, while 19% are professionals like doctors, lawyers and accountants.

Aside from the training time, which takes participants away from work and family, the biggest single cost cited by experts is the bike. “You can spend $10,000 on a bicycle,” says Connie Carson, a triathlete and board president of Team CWW, a company that trains triathletes. According to Szufnarowski, it’s hard to buy a good-quality bike for under $1,000.

Training for the swim portion of a race can also be pricey. “Swimming can be very expensive if you don’t have access to an inexpensive pool,” says Denis Calabrese, the founder of USA Fit, which trains athletes for marathons and triathlons in 53 cities across the U.S. and Canada.

Aside from getting pool time, many athletes find it necessary to get professional swim coaching, says Szufnarowski, especially in open water, which is a very different experience than swimming in a pool. While Szufnarowski charges $75 per hour for individual swim lessons, Carson says many private coaches in the Denver charge $100 or more per hour.

In addition to having a lot of discretionary income, triathletes also happen to be on the older side, according to USA Triathlon’s study. This may be surprising, considering the popular Olympic-length triathlon combines a nearly one-mile swim, a 25-mile bike ride and a 6.2-mile run. (The well-known Ironman triathlons are even more intense, wrapping the race up with a full, 26.2-mile marathon.)

USA Triathlon says the greatest participant growth since the late 1990s has been in the 35-39 and 30-44 age groups. The average age of triathletes is 38. And a sizable number are even older: Over 12% of competitors are over 50.

Szufnarowski says the average age of triathletes she trains is around 47. “I find that as people experience a big birthday, like 40 or 50, they want to do something fantastic,” she explains. “The multisport aspect of a triathlon … mixing all three is actually quite forgiving on a body that’s getting older.”

How to Compete in a Triathlon Without Spending a Fortune

While it’s easy to spend a lot of money training for a triathlon, beginners can also manage to try out the sport without putting down a lot of money. Triathlon coaches share their three best tips for training on the cheap.

No. 1: Don’t buy a new bike.

“A lot of people over-buy on the bike,” says Booher. He says first-time triathletes should consider buying a used bike from experienced competitors looking to upgrade.

“New bikes are like cars –they take a 30% hit in the first year,” he says. To find a seller, Booher suggests checking out Craigslist, or reaching out to the members of local triathlon clubs.

Szufnarowski says many local shops will also rent high-quality road bikes. In Orange County, she says local shops will rent a triathlon-ready bike for eight weeks for $100. And for sprint-distance triathlons, which are the shortest races, Austin YMCA triathlon program director Ron Perry says in most cases, the bike already sitting in the garage is acceptable-- even if it’s not tailor-made for racing.

No. 2: Stick to your region.

While many competitors like the idea of competing in an exotic locale, TriNewbie.com founder Hazen Kent says the smarter and more budget-friendly option is to find a local event. This way, Kent says athletes can skip the added expense of hotel rooms and travel costs, as traveling with all of the athletic gear can get pretty pricey – especially when the race is an airplane trip away.

“You’ll have to transport your bike as well, and you often can’t bring it into the plane – you have to get it checked,” says Bree Soileau, who runs Alamo 180, a triathlon training company in San Antonio, Texas. “You’ll also have to take it apart, put it in a bike box, and then have a bike shop reassemble it if you’re not any good at it,” she adds, which can cost anywhere from $150 to $200.

No. 3: Consider group coaching.

While many triathletes turn to private coaching for the individualized support and motivation, experts say group coaching can be equally effective, and much more affordable. For instance, Szufarnowski charges $75 an hour for individual swim coaching, but the price tag drops to $60 per month for group coaching. And Carson’s Team CWW charges $350 for training from March to August.

Soileau adds training with a club or coach can help prevent injuries that bring high medical bills. “Injuries can be common if you don’t know how to train properly.” She adds that many athletes train excessively, resulting in overuse injuries. Improper form can also lead to unnecessary strains or injuries that might have been easily prevented.

“You’re more likely to get injured because of repeated use,” says Booher, if trying to train without guidance. “You can spend a lot that way on doctors, MRIs and knee surgery.”

Follow Gabrielle Karol on Twitter @GabrielleKarol