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The Endangered Outdoor Ride

In the past several years, indoor riding has become a bona fide trend at the elite level of the sport, and that trend has begun to trickle down into the age group ranks.

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This story was originally printed in the March/April issue of Inside Triathlon magazine.

Meredith Kessler is one of the better cyclists in triathlon. Her typical Ironman bike split is in the 5:10 range. Pretty good for a full-time office worker and longtime age-grouper who waited until she was 31 to turn pro.

So what’s her secret? Simple: riding indoors.

“I ride outside once every other weekend,” she says. “That’s it.”

The rest of Kessler’s bike training is done under a roof, specifically that of Velo SF, a facility for group indoor cycling classes in downtown San Francisco. The 2010 Ironman Canada champion teaches four or five 90-minute sessions there each week. Each session incorporates high-intensity efforts that seem to do more than merely make up for any additional saddle time she might have if she always rode outdoors.

In fact, Kessler knows for a fact that her indoor-based bike training program is more effective than outdoor riding, because she used to do most of her riding outside. That’s when she used to complete her Ironman bike legs in six hours. Her bike performance breakthrough coincided precisely with her move indoors, in 2007.

Kessler is not alone in finding success with indoor-based bike training for triathlon. In the past several years, indoor riding has become a bona fide trend at the elite level of the sport, and that trend has begun to trickle down into the age group ranks. Also at the vanguard of the trend is Kessler’s fellow San Franciscan Tyler Stewart, who teaches three classes each week at Velo SF and rides outdoors once on the weekend. All of the indoor rides involve high-intensity intervals, and most of the outdoor rides are fairly short—seldom more than four hours.

“I typically do no more than 10 rides of more than four hours before an Ironman,” Stewart says.

Stewart feels she gains so much fitness from her high-intensity indoor rides that she can maximize her Ironman bike performance without ever logging more than 10 hours of saddle time in a single week. The results speak for themselves: Stewart owns bike course records at Ironman Florida (4:47:59) and Ironman 70.3 Vineman (2:23:55).


No elite triathlete has taken the indoor cycling trend farther than 2010 Ironman Coeur d’Alene and Ironman Cozumel winner Andy Potts. Until 2009, Potts did all his bike training indoors. The only time he rode his bike outdoors was when he was racing. Under the guidance of coach Mike Doane, Potts rode a Computrainer in his garage for two-and-a-half hours per session, six times a week, including high-intensity work in most of those workouts.

“When I get on the bike, it’s very dedicated riding,” Potts says. “It’s very focused. Everything is written down to the minute. When my coach writes my workouts, each minute is accounted for, as opposed to, ‘Oh, just ride out to such-and-such place.’”

This is the benefit that all triathletes who are sold on indoor cycling point to. Riding inside is conducive to “high-quality” training. There are no stoplights to stop for, no descents to coast down, and no other cyclists to draft behind. Motorists cannot distract you from the task at hand, weather conditions cannot slow you down. The idiosyncrasies of the roads do not affect your workout. Instead, you are free to perform exactly the workout you design.

Beyond all that, the indoor trainer, much as the pool does with swimmers, encourages athletes to divide their workouts into variable-intensity segments to stave off the boredom of training in a confined space. Consequently, athletes spend more time working at higher intensities on indoor trainers than they do outdoors—and they get fitter in the process.

It’s probably no coincidence that triathletes with swimming backgrounds, like Kessler and Potts, are leading the indoor cycling trend.

“I think it was my mentality of growing up as a swimmer,” Potts answered when asked why he chose to buck tradition and ride exclusively indoors at the start of his multisport career. “I didn’t have any problem following a black line. Mentally it doesn’t exhaust me—it doesn’t drain me. I’m able to engage my mind in other things while I’m doing that activity. So it almost became a challenge.”

It would take an impossible experiment in which Potts cloned himself and trained outdoors to determine whether his indoor routine gave him the best possible race results. But the results he’s achieved suggest it didn’t hold him back. Most notably, Potts scorched a 2:04:28 bike split to set himself up for victory in the 2007 Ironman World Championship 70.3.


Andy Potts does much of his bike training indoors. Photo: Nick Salazar

While Potts has taken triathlon’s indoor cycling trend to its ultimate extreme, he did not start the trend. That distinction clearly belongs to former pro and longtime coach Troy Jacobson. Back in 1992, when Jacobson was just 23 years old, he taught an indoor cycling class for competitive cyclists and triathletes in the Baltimore area.
“My first class was at a Performance Bike shop and I had three people who paid me $3 each,” he recalls. “Within a month I had over 25 people at that Wednesday night class and was giving other classes at different shops on other nights throughout the week. The athletes brought their bikes and trainers and loved the intensity and camaraderie.”

Less than two years later an executive at the advertising agency representing indoor cycling equipment manufacturer CycleOps took one of Jacobson’s classes and loved it. He put Jacobson in touch with the principals at CycleOps and in 1995 the two sides partnered on a video called “Cyclerobx.” Featuring an all-star cast of guest instructors, including Ironman world champions Greg Welch and Karen Smyers, the video sold tens of thousands of copies.

Inspired by this success, Jacobson lined up his own investors in 1997 and began filming a series of indoor cycling workout videos called “Spinervals,” which proved equally successful. “Now we have over 40 DVDs and international distribution and we’ve sold several hundred thousand copies,” says Jacobson, who proudly notes that his Spinervals brand is now used generically in reference to serious indoor cycling workouts.

Now based in Tucson, Ariz., Jacobson coaches triathletes across the country and beyond. He encourages them to do some, but not all, of their bike training indoors. “Most of the athletes I coach use the trainer two to three times a week,” he says.
For him, coaching these workouts is as easy as telling them which “Spinervals” video to put in the DVD player. “I can tell them to do Spinervals 12 for a nice recovery ride or Spinervals 22 for a great time trial/tempo ride,” Jacobson says.

Because indoor cycling has a long history in triathlon, the most effective ways to do it have been pretty well worked out. So if you’d like to implement indoor training into your routine, don’t reinvent the wheel, so to speak. Model your indoor bike training after the recommendations of those who know.


Rule No. 1:  Go for maximum time efficiency.
Incorporating indoor cycling into your training presents an ideal opportunity to trim the waste that more than likely exists in your current routine. Increasing the time efficiency of your bike training starts with trading some volume for intensity, but it goes beyond that.

“The approach I’ve taken is to incorporate a modest increase in training intensity (more time at threshold across all three disciplines and more time above threshold as well) and an increased focus on specificity,” says Chris Carmichael, author of “The Time-Crunched Triathlete.” “That’s why the majority of the workouts in ‘The Time-Crunched Triathlete’ are brick workouts.”

Both Kessler and Potts do a short to mid-length run after every indoor ride to maximize the fitness bang they get for their workout buck.

“When I do clinics I tell people that if you have an hour and a half to work out, you’re better off doing a one-hour indoor ride and a 20-minute run than a 90-minute outdoor ride,” Potts says.

The amount of riding time you slash and the amount of high-intensity riding you add should depend on individual considerations. You’ll definitely want to retain one weekly endurance ride that’s long enough to give you the endurance you need to go the full race distance. Two high-intensity indoor rides per week are appropriate for most triathletes. None of these rides needs to last longer than an hour.

In 2009, inspired by the likes of Kessler, Stewart and Potts, I transitioned to a bike training regimen that consisted of three one-hour indoor rides and one long outdoor ride (up to five-and-a-half hours) per week. Two of those indoor rides were high intensity. One was some form of threshold ride (e.g. 30 minutes easy, 30 minutes at lactate threshold intensity) and the other was some form of interval ride (e.g. 12-minute warm-up, 12×1-minute sprints with 2-minute spin recoveries, 12-minute cool-down). This regimen represented a 20 percent reduction in my previous cycling volume, and yet, at age 38, it lifted my bike performance to a new lifetime high.

I was sold.


Rule No. 2:  Don’t take it too far.

After riding exclusively indoors for several years, Potts incorporated some outdoor cycling into his training last year, and plans to continue. Why?

“It helped my bike handling a little,” he says. “I think it helped a bit with my cadence, too. I feel you can get lulled into a grinding cadence on a Computrainer. It also helps with the mental game of battling elements and conditions. And physiologically I’m able to push higher watts outside than inside.”

It only makes sense: Since you race outdoors, you need to do some training outdoors. Failure to do so will leave you less than ideally prepared for the elements of outdoor cycling that are different from indoor cycling.


Rule No. 3:  Consider a group boost.

If riding indoors is a trend in triathlon, then riding indoors in a group setting—as Kessler and Stewart do at Velo SF—is a trend within that trend. Of course, indoor cycling classes have existed for a long time, but indoor cycling classes designed especially for competitive endurance athletes are much newer.

The typical fitness club Spin class is a good workout, but not a triathlon-specific workout. Those who sign up don’t use their own bikes and can’t use power to monitor and control their workout intensity. The workouts themselves don’t focus on the intensities that triathletes need to develop, are not progressive and often are not challenging enough for serious triathletes.

All across the country, endurance performance centers are opening their doors for business and offering group indoor cycling workouts for athletes, typically alongside other classes and services such as functional strength workouts and physiological testing. In addition to Velo SF in San Francisco, there’s Aire Urban Performance Co Operative in San Diego, Tri on the Run Fitness Center in Houston, and Target Training in Westport, Conn., to name a few.

Henry Heisler is an IT project manager and age-group triathlete who frequently rides indoors at Well-Fit, an endurance sports training facility in Chicago. He says, “The advantage to group cycling workouts versus riding at home is the motivation provided by a group, especially for the more challenging strength or intensity workouts.

“The social aspect is great too,” Heisler adds. “When you’re on Computrainers for a couple of hours and sitting a few feet apart, there are all kinds of conversations happening. Since you’re indoors, talking to the person riding next to you is easy. I’ve made many friends and found a lot of new training partners during those indoor rides, especially early in the year when Chicago is cold and riding indoors at Well-Fit is that much more attractive.”

While group indoor riding offers clear advantages compared to solitary indoor riding, some coaches believe that there is also a disadvantage and that group indoor riding should not be done to the exclusion of solitary indoor riding.

“Indoor training by yourself requires a great deal of focus,” says Carmichael, “and triathletes—especially Ironman triathletes—need to learn how to be alone with themselves and how to stay motivated to push themselves. To develop as a complete athlete, I think people need to spend time training both in groups and solo.”


There are no absolutes in triathlon training. There is no single type of training that is so good it should become your only way of training.

But indoor cycling appears to be a better way of training than it was previously thought to be. That’s why more triathletes are doing more of it lately, and it’s why you might need to consider doing more indoor cycling yourself.

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