Zwift + Wahoo Kickr Core Review
As an almost 40 year-old raised playing competitive team sports, I still itch to take the field. That said, lots of things can make scheduling this time difficult: family commitments, work, and an aging body are just a few of the excuses. That’s why I’ve found group road cycling rides here in Fort Collins, Colorado to be an almost-perfect solution for my middle-aged competitive needs.
In my cycling bubble we have standing hard group rides during lunch on Tuesday and Thursday, Wednesday evening (two options), and Saturday morning. There’s no need to coordinate ad-hoc times with friends and the low-impact nature of cycling makes it a lot easier to do a couple of these hard rides each week.
However, you know what’s not fun about group rides? Hanging off the back, struggling for air. That was my default mode of operation during the spring and early summer as I usually spent the colder months off the bike. To make these rides consistently more fun, I decided to dive into a smart trainer setup. Here’s an overview of my setup, a review of the key parts, and an answer to the key question: does work on a smart trainer translate to real-world group rides?
My Indoor Training Supplies
- Zwift - multiplayer online cycling training program ($14.99/mo)
- Wahoo Kickr Core - smart bike trainer ($899.99)
- Strava - training activity tracker ($60/yr)
- MacBook Pro (2014)
- Fan
- Wahoo USB ANT+ Dongle & Extension Cable Kit - provides better connectivity than the Mac’s bluetooth ($39.99)
- Wahoo TICKR - Heart rate monitor chest strap ($49.99)
- Floor mat - collect the sweat
- Wahoo Kickr Snap Wheel Block - keep the bike level ($19.99)
Some notes on my equipment:
- Initially I used an optical heart rate monitor on my arm, the Wahoo TICKR FIT. However, the numbers didn’t pass the eye test: my heart rate would drop off a cliff at the end of a workout (when I’d expect it to be a bit a higher than the beginning) and in general the numbers were always lower than I’d expect. The chest strap (Wahoo TICKR) reports the numbers I’d expect.
- I started by connecting my devices (the Wahoo Kickr Core and Wahoo TICKR) to my computer via bluetooth. However, I experienced intermittent connectivity issues with the bluetooth connection. Connecting by ANT+ via the Wahoo USB ANT+ Dongle resolved all of my bluetooth dropouts.
- A good fan is critical. I didn’t use one as the weather turned warmer and I’d drop five pounds of water in an hour workout. My workouts were pretty terrible. Adding a solid fan left me feeling much better.
Why try indoor training now versus ten years ago?
Indoor training for cycling has evolved considerably over the years making the act of riding your bike without moving more rewarding. I’d describe the evolution as three eras:
- The Rocky V Era - just throw your bike on a set of rollers or basic trainer, turn on your favorite cycling video, and ride. Perhaps you use a heart rate monitor, but beyond that, you’re riding natural.
- The Smart Solo Era - Connect your smart trainer to a computer so it can control the resistance and generate tailored workouts. Apps like Trainer Road ($19.99/mo) and The Sufferfest ($14.99/mo) provide this.
- The Multi-Player Era - Zwift enters the scene, providing virtual worlds where cyclists use their smart trainers to race against each other in realtime.
Tangentially, Peleton (from $2,245 or $58/mo for 39 mos) emerged within the Multi-Player Era of indoor cycling training as well. Like Zwift, Peleton provides a real-time group environment. Peleton is targeted at in-person cycling class participants like Soul Cycle rather than avid outdoor cyclists.
Why has indoor training evolved this way? It’s all about motivation. In the The Rocky V Era, it was up to you define workouts and get your heart rate into the proper zone. That’s easy to let up on. The Smart Solo Era made it easier to stay motivated by setting power and interval lengths for you and you see your metrics (power, heart rate, cadence, etc) following a workout. It’s motivating to hit the workout’s prescribed numbers. Finally, the The Multi-Player Era taps into our innate competitive instinct: it’s hard to resist chasing a rider up the road even when they are just a collection of sprites on the screen. It’s easier than ever before to stay motivated on a trainer.
Setting up the Wahoo Kickr Core and Zwift
Connecting all of these parts isn’t too bad:
- Remove the rear wheel of the bike. Connect the bike to the cassette on the Wahoo Kickr Core. You’ll need to purchase and attach your own cassette to the Kickr. I had the bike shop where I purchased the trainer do this for me.
- Turn on your computer, power up Zwift.
- Connect the USB ANT+ doggle
Zwift should automatically connect to the trainer and heart rate monitor.
Zwift riding options
There are several ways to use Zwift. Here’s the primary ways:
- Free Ride - Just pick a world and ride. You’ll be in the virtual world with other riders across the globe. Zwift adjusts the trainer resistance as inclines increase on the virtual road and drops it down when you’re descending.
- Workouts - Pick from many individual workouts, organized by their total time. Workout difficulty is based on power zones determined from your FTP.
- Training Programs - In addition to individual workouts, Zwift also provides collections of workouts called training programs (ex: 8 week race prep).
- Virtual Race - Race against others in a virtual world. Riders are grouped in one of 4 categories based on their FTP (you pick the category). There are typically multiple races every hour.
- Group Training - Similar to a virtual race, you can also do a group training ride. There are two primary types of training rides: hour plus rides that attempt to ride at a constant watts/kg and interval rides.
I use the individual workouts and virtual races. I spend my soul riding time outdoors, so I don’t use the free ride option. I find it hard to stick to a long training program with many varied workouts as it is hard to gauge my progress when the workouts change so frequently. Finally, the group training felt like a bit of a mess. Because riding in a group is motivating - even in a virtual world - many folks end up pushing the pace and it ends up resembling a race anyway.
How does riding on a trainer feel versus the road?
While riding your bike on a stationary trainer still feels a lot like riding the same bike on the road, I’ve noticed some differences:
- Keep Pedaling - Unlike riding on the road, your pedals are always moving when using a smart trainer. Other riders don’t coast in Zwift and when using ERG Mode in a workout (the default) the trainer sets the resistance for you. If you stop pedaling, it’s a bear to get the pedals moving again. I don’t think this behavior is a negative as it makes my trainer rides more efficient than training on the road. An hour on the trainer feels like two hour ride on real roads.
- Harder to move from a seated to standing position - It feels like considerably more work shifting to a standing position than it does on the road. I believe this is because there are no inclines and you need to keep the pedals moving when in ERG mode.
- Less shifting - I never use my small chain ring on the trainer and only shift between a couple positions on the cassette. Shifting is not as smooth as in the real world.
Because of the constant pedaling and less dynamic positioning on the bike, initially I was more sore than on an outdoor session. This got better over time.
My basic training program
I believe in consistency more than sticking to a workout program I don’t want to do (I’m not getting paid to ride my bike). I enjoy listening to the Velonews Fast Talk and they regularly cover training. There were two theories that hit home for me:
- Short sessions in the winter - On one episode, a coach from Toronto advocated for keeping indoor training sessions short (an hour or less) versus traditional large endurance block in the off season. I live in a cold weather climate and long, cold endurance rides sound very demotivating. So does doing long trainer rides in my garage. Why not push these long rides do the warmer spring months?
- Stick to a few basic workouts - Zwift has multi-week training programs where each workout is different than the last. On one episode, a coach advocated for keeping just a few workouts in rotation. This makes it far easier to track your progress. For me, I stick with 2x20’ and 5x5’ intervals as they each stress my fitness in different ways and work well on the trainer. I’ve found short intervals (say 30 seconds or less) to be really awkward on a trainer with ERG mode. Rotating just two workouts would get very repetitive, so I mix it up with some sweet spot rides and Zwift races.
- Polarized training - It’s very hard to ride slow and do a proper recovery ride in the real world. With a smart trainer on ERG mode, this is easy. After an interval day I’ll do a recovery ride on the trainer.
A typical winter week might look like this for me:
- MON - 50 minutes Sweet Spot
- TUE - Zwift Race
- WED - Recovery ride/jog & weights
- THU - 2x20 intervals
- FRI - Recovery ride/jog & weights
- SAT - 5x5 intervals
- SUN - Rest or Recovery ride/jog & weights
I’ll also substitute a Zwift race for a 2x20 interval (more on this below). If I feel like a big endurance day I’ll try get out for a backcountry ski versus a cold day on the bike.
Zwift racing
Zwift’s bread-and-butter is the virtual racing environment. Zwift has several virtual worlds (three based on real-world locations and one fictional) that host races. There are typically races every hour of the day with varying distances (most take between 40 minutes and 1 hour 20 minutes) and types of courses (flat, hilling, long climbs). When you sign up for a race, you also pick your category (from A-D with A being an FTP of 4.0 w/kg or greater).
I was pleasantly surprised to find these races to be very motivating. Just like the real world, you ride in a pack and if you are on the front, you need to do more work. You can soft pedal to drop off the front. There’s race dynamics: you can tell that at the end of the race other riders are trying to stay off the front while keeping the pace going. On inclines it’s all about your w/kg (factors like wind don’t come into play). There are also several rough sections (dirt, cobbles) where pure power wins.
Zwift races start very, very hard. After a couple of minutes, they settle into a pace. I’d classify races as an hour-long FTP session if you are going hard. Because of this feel, I’ll substitute a race for a 2x20 session if I feel inclined.
Just like the real world of sports, it’s not a level playing field in races. Since w/kg is vital for any race that includes climbs it’s common to see riders stretching the truth on their actual weight. I’ve seen this by comparing race results with linked Strava profiles - somehow a rider that easily looks 180 lbs loses in a photo drops 40 lbs in Zwift.
Another factor that Zwift doesn’t account for is that your FTP lowers as altitude increases. I ride at about 5k feet here in Colorado, which means my FTP is about 5.6% lower than at sea level. If my FTP is 300 watts, my FTP at sea level would be nearly 317 watts. That’s a pretty big difference in a race.
I think the best mental strategy when doing a Zwift race is to focus less on your place and more on your numbers. There’s always a group to ride with and compete against. It feels the same whether they are truthful about their weight and whatever altitude they reside in.
Does it translate to group rides?
The reason I considered riding stationary, staring at my dusty garage wall is to enjoy group rides for a greater portion of the year. While these COVID times prematurely aborted the group riding season, I felt better in the handful of group rides I was able to do in the spring of 2020. The one area that is difficult to replicate on a trainer are the short, high-power surges that occur on a group ride. I struggled with these initially but in a few weeks had adjusted for these. I’m OK with that - just don’t be disappointed if you notice the same problem.
Do I use an indoor trainer in the summer?
Surprising, I’ve found myself continuing to ride the trainer during the warm weather months. I’ve done this for three reasons:
- Better for hard training rides - An interval ride is just as hard indoors or outside. When I do these indoors, I don’t have to worry about traffic, flats, or other issues.
- Better for recovery rides - A smart trainer showed me how slow I really need to ride to do a recovery ride. I realized I likely never performed a proper recovery ride in the wild.
- Outdoors is for the soul - Since my structured time is indoors, this frees my soul to ride outside by feel. Indoors is for structure, outdoors is for freedom.
Summary
Using the Wahoo Kickr and Zwift helped me build my FTP (or at least keep in reasonable) at the start of the group riding season in the spring without suffering through long cold weather rides. The virtual world of Zwift is almost as motivating as the real world and helped me ride consistently through the winter. I continue to use the indoor trainer during summer for short, high-intensity workouts and dedicate outdoor to riding by feel.