Is ERG mode killing your training?

With the advent of the smart-trainer, indoor turbo sessions have made a massive leap into the 21st century. In addition to allowing you to capture and review performance data from your workouts, many smart trainers also offer what’s called “ERG Mode”. This mode allows the The Sufferfest Training System to dynamically control the resistance of the trainer to match a given workout profile. We call it “AARGH Mode”, or “The Minions in the Machine”.

Tell The Sufferfest Training Centre what your Functional Threshold Power (FTP) and it sets power targets for the workout based on that value. Trainer resistance is automatically adjusted so you are forced to hit those targets, whether you like it or not.

While ERG Mode does represent some serious next-level Suffering, there are some situations in which good old slope or “dumb trainer “ mode may be a better option. Today we’re going to break down the pros and cons of ERG Mode so you can use it—or not—most effectively.

ERG Mode and Pacing

One of the biggest problems athletes have when it comes to training is pacing themselves during an interval. All too often riders start out an effort well above a sustainable pace. One reason is that innate Sufferlandrian impulse to turn it up to 15 and rip the knob off. Another is athletic optimism. When you’re fresh it really does feel like you could hold that effort. By having a smart trainer control your effort it forces you to pace it correctly. This gives you a much better idea of how RPE can shift throughout a single interval, or throughout an entire workout.

Revolver is the perfect example. If you’re not familiar with this little slice of Sufferlandrian sadism, you are tasked with holding roughly the same power for 15 (more or less...) 60 second (mostly...) intervals. When you naively stroll into interval number one, the first 10 seconds feel like a cool breeze carrying scents of bergamot and Couchlandrian coffeecake. By the last 10 seconds of the 15th 16th, interval you’d swear that someone replaced the fine blood you usually have in your body with dark, smouldering lava crystals. While they feel different, they should be done at the exact same effort for maximum benefit. That is where ERG mode really makes a difference. It’s far better to hit all 15 16 efforts at the same, barely sustainable effort, rather than destroying yourself on the first few only to whimper and soft pedal through the last half of the workout..

ERG Mode = AARGH Mode: There is No Escape

Not only does ERG mode hold you accountable during the actual intervals, but it also keeps you in check during the recovery between efforts. Despite our best efforts, when riding a normal trainer or outside, the tendency is to completely back off the power as soon as you finish a hard effort. With ERG mode you still get to recover, but at a level that is more active recovery than spa day.

Lastly, ERG mode also helps you deliver consistent power over a given effort. Our natural tendency is to surge and ease off power at random times. With ERG mode you don’t have that option. The trainer will increase and decrease resistance in response to your output, resulting in consistent power, whether you’re pedalling at 70 rpm or 110 rpm. This allows you to complete workouts exactly as they are intended, meaning you maximise your training time and ultimately your Return on Suffering.

When To Resist the Urge to ERG

Despite these benefits there are times when ERG mode can actually be detrimental to a given session. The most obvious is during sessions when you are trying to determine your Functional Threshold Power, or FTP. If you haven’t been to see the doctor for a dose of tough glove that is Rubber Glove, you’re in for a….treat. The whole idea of doing a power test like Rubber Glove is to determine the absolute maximum effort you can sustain, allowing you to set your FTP for future suffering. The issue with ERG mode is that The Sufferfest Training Centre sets the power targets for all of the efforts in a workout based on your  current FTP. It’s a classic Sufferlandrian Catch 22: how can one possibly know the percentage of one’s old FTP that is sustainable for 20 minutes when the reason for the Dr’s Visit is finding your new FTP?

The main limitation of ERG mode is this: all effort levels are based off of your your FUNCTIONAL Threshold Power. That F-word makes all of the difference. FTP isn’t a fixed value. It’s  a fluid, ever-moving target, one that can change from week to week and even day to day. When you’re on the bike you have your own internal Suffer-meter that tells you whether pushing 220 watts feels like a 5 out of 10 or an 11 out of 10 on any given day. 

As smart as it is, your smart-trainer isn’t plugged into your Suffer-meter. You’re going to have days when you feel like your legs are made of Couchlandrian balsa wood. Everyone does. Sometimes it’s because you are at the tail end of a 2 week block of structured suffering and your body is reaching its limits.  Or maybe you just didn’t eat and drink enough before entering your torture chamber.  On those days your FTP might be 5% lower than when you last did Rubber Glove. Again with the F-word. What is Functional Threshold Power one day won’t necessarily be the next. That’s normal.

You have to put your ego aside and listen to your body, it knows a thing of two. Take the hint and dial back the intensity of your workout by 5% or so. If you don’t and insist on pushing it, the chances are you’ll overextend yourself, not complete the workout, and send your mental state into a Downward Spiral that is more toilet-like than Sufferlandrian, all because of a single bad session. But remember: a single bad session does not a Couchlandrian make. It simply means that you need to rest and recover as enthusiastically as you Suffer.

The opposite can also be true. After several weeks of good, consistent Suffering, and *gasp* proper rest,  your FTP might have gone up 5%. Unless you’ve booked an appointment with The Doctor, your smart trainer would have no idea. It can’t read your mind. You might end up breezing through a workout that was supposed to leave you with a third-class, one-way ticket to grovel town. That means you didn’t quite Suffer like you should have, and that makes GvA shed a tear. 

Apart from Rubber Glove, there are two other videos that simply aren't suited to completing in ERG mode: Violator & Half Is Easy. These short, rapid fire, on/off efforts are best done in slope mode, so you can unleash your high speed and power for each effort (without waiting for the resistance to ramp up).

With ERG Mode, there is nowhere to hide. There is no try, there is only DO.

Every tool has its purpose. Building a house? Use a hammer. Dialing in your carbon race bike? Maybe try something less...hefty. Pacing, accountability, consistency—all of these are made easier by ERG mode, that beautifully nasty Minion in the Machine. But tools are only as good as the craftsman who uses them. When it comes to establishing baseline metrics like FTP, or when your body is telling you something different, let your smart trainer play dumb and get reacquainted with your shifters. They’ve missed you.

Read more from Mac Cassin

Mac Cassin has been coached by Sir Neal Henderson since 2009 and is a coach at APEX Coaching, with a focus on masters and junior racers. As an elite cyclist who also has to balance the demands of ‘life’ with his goals as an athlete, Mac has a deep understanding of how to get the most out of those who have limited time to train. Mac has raced at the World and PanAmerican championships and holds several US national and state titles. His studies were in Integrative Physiology from the University of Colorado and has worked as a research assistant in the CU Neurophysiology lab.

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