Which Type of Indoor Training for Which Workout?

Our guide to the most efficient way to make your training plan fit with different indoor cycling activities.

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You can train all six physiological abilities (aerobic endurance, speed skills, muscular force, muscular endurance, anaerobic endurance, sprint power) while riding inside. To make the most of your training, you can align the ability you’re training with the type of indoor cycling that’s best suited for it.

RELATED: Triathlete’s Guide to Indoor Training

Aerobic Endurance (AE)

Recovery rides and aerobic threshold rides can certainly be done alone, but having virtual company through an interactive app can be helpful. A lot of riders skip recovery rides indoors because it seems like a waste of time to get on an indoor trainer just to go easy. But indoors or outdoors, recovery rides serve an important purpose and, for the highly experienced rider, are better for your training progression than not riding at all. Getting together with a club or a friend through an interactive indoor cycling app can provide the incentive necessary to get on the bike. Having company can also help keep your easy ride easy. Riding too hard during a recovery ride is a mistake coaches see all the time, and peer pressure from a group is a good way to enforce the “go easy” mantra.

Aerobic threshold rides tend to be your long rides of the week. These are zone 2 rides at a conversational pace or the zone 2 portion of a combined ride where you might spend an hour at aerobic threshold and include a speed skills or muscular force set in the middle. Long zone 2 rides outdoors are great to do solo and can certainly be done solo indoors, but many riders find them more enjoyable when connected to apps that feature video and virtual courses, or with groups through interactive apps. It may be difficult to find long aerobic threshold rides at indoor cycling studios, however, because “moderate and steady” isn’t very marketable.

Speed Skills (SS)

You can sneak these cadence and pedal-stroke drills into interactive virtual group rides or even during live indoor cycling classes. It’s just a matter of changing your focus and perhaps your gearing or resistance. Whether you’re riding inside alone or with a group, you have to reduce the resistance on the trainer to accomplish these drills, particularly spin-ups and 9-to-3 drills. Riding in erg mode on a virtual course makes this difficult because the trainer is setting the resistance based on your weight and the grade of the virtual course. You can either do them on a virtual descent when the resistance lightens up or switch your smart trainer to level mode and reduce the resistance manually. With old-school trainers, shifting into a light gear will do the trick because even with a high cadence, you’ll be at the low end of the trainer’s power curve. A more advanced version of spin-ups and 9-to-3s is to ride with a high cadence at zone 4 because the end goal of working on your pedal stroke is being able to pedal quickly at high power outputs.

The isolated-leg drills are often executed better indoors than outdoors. If you are using your bike on a stationary trainer, you can either unclip and rest your foot on a stool or stable part of the trainer or stay clipped in and just let the “resting” leg go around. The point of the isolated drill is to feel and minimize the “dead spots” at the top and bottom of the pedal stroke. Without the power of the opposing leg, you’ll notice how little force you exert from about 11 o’clock to 1 o’clock and after the 5 o’clock position. As with the 9-to-3 drill with both feet, aim to kick your foot across the top of the stroke and pull through the bottom of the stroke when pedaling with one foot.

Muscular Force (MF)

Flat force and hill force intervals are short efforts (6–8 pedal strokes for each leg) that require high torque to accelerate against heavy resistance. For indoor training, these are best done alone or in a specific group workout where everyone performs the same workout. They are harder to do during an interactive group ride. If you have a smart trainer with a “level” setting, increase the level so the power curve starts out high. Otherwise, you are more likely to spin up too quickly before encountering sufficiently heavy resistance. Riders with rear-wheel or direct-drive trainers with fluid or wind resistance will need to start in a large gear. If you have a magnetic resistance unit on a specialized indoor cycle, like a Peloton, you’ll have to increase the resistance significantly so you have substantial resistance to getting the freewheel moving. You don’t have to start from an absolute standing start, but you want the cranks to be moving very slowly to start the intervals.

Muscular Endurance (ME)

Tempo, cruise, and sweet spot intervals are among the most common intensities you’ll see in preplanned structured workouts in indoor cycling apps. These intensities can also be pretty easily incorporated into virtual group rides on interactive apps even if it’s a free ride rather than a structured workout. Because the interval durations for muscular endurance ability workouts range from 6 to 20 minutes at specific power outputs, they are well suited for erg mode or a manual resistance setting at a target power output. If you are just looking to accumulate time at intensity, erg mode works great for these efforts. When you are looking to transition your riding to outdoor training and events, it is important to spend some time doing these intervals on level mode or on a virtual course so you can learn the pacing and motivation necessary to reach and hold the appropriate effort.

Anaerobic Endurance (AnE)

VO2max intervals, pyramid intervals, and group ride work is what indoor cycling setups do best. The VO2max intervals and pyramid intervals feature short efforts of 30 seconds to 3 minutes and a total work time of 3 to 15 minutes. The intensity of the efforts is power zone 5 or an RPE of 9 out of 10. Erg mode on a smart trainer is not the best way to execute these intervals because the point is for you to reach and maintain the highest power output you can sustain for the duration of each interval. It is better to use the level mode on a smart trainer for these or rely on the power curve of a fluid or wind resistance unit.

With magnetic resistance units on dedicated indoor cycles, the only complication is that you need to manually increase the resistance level to start the interval and then manually reduce the resistance for recovery periods. When the intervals and recovery periods are extremely short (30-second efforts with 30-second recoveries, for instance), that can get difficult to keep up with—especially as you fatigue from the efforts.

When I want an athlete to truly give everything they have during VO2max intervals or pyramid intervals, I make them execute the workout indoors for their own safety. If you really go all-out for five 3-minute VO2max intervals, you will be gasping for breath and have nothing left at the end. I’d rather a cyclist or triathlete close their eyes, drop their head, and hunch over the handlebars on an indoor trainer than have them do that on a road or trail. To compete outdoors, you will need to be able to control the bike while exerting that much effort, but during the process of training, indoors is the safest place for max effort intervals.

Virtual group rides, e-races, and in-person live cycling classes are other logical places for anaerobic endurance work. Depending on the app settings, one of the benefits of virtual group rides and in-person classes is that you can’t get dropped, so you don’t have to hold anything back. In the real world, athletes almost always hold a little bit of power in reserve so they have something left in the tank to avoid getting left behind after their city limit sprint or hard pull on the front of the group. Many cyclists who compete in e-races note they are often more difficult than any real-world race they competed in, and the lack of risk—either from crashing or being physically left behind—may play a role in allowing riders to reach higher power outputs and sustain them longer.

Sprint Power (SP)

Sprint power main sets—form sprints, jumps, and group sprints—can be tricky on rear-wheel and direct-drive trainers because of cyclists’ tendencies to swing the bike side-to-side while driving downward with each pedal stroke. When the bike has a stable and immovable base, your movement on top of the bike won’t be as effective and can be counterproductive. However, there are benefits to sprinting indoors. Just like riding an indoor trainer can help you correct a choppy pedal stroke, sprinting on an indoor trainer can help you deliver power to the pedals with less side-to-side movement.

Group sprint workouts can be accomplished with a structured workout in an interactive app, more informally during a group ride or e-race, and as part of in-person live cycling classes. When it comes to real-world racing it is important, however, to spend time practicing sprints with other riders close by. Not only do you need real-world sprint practice to learn how to gauge the timing and intensity of your efforts, but you also need to be comfortable in the close quarters of a group ride or racing situation. At the end of an outdoor race, you have to pick your line, maneuver with the riders around you, and keep yourself and everyone else safe.

Adapted from Ride Inside by Joe Friel with permission of VeloPress.

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