ERG Mode: What is it & When to use it

We are deep in trainer season. Workouts are getting longer and the body is getting restless for the outdoors. But we press on with our indoor rides to improve or maintain our fitness. I’ve had a lot of discussions recently about ERG Mode, so I thought I’d give my opinions on when to use it.

What is ERG Mode?

ERG mode is a feature on smart cycling trainers that allows either the app you are using, or the trainer itself to set the resistance you experience. For example: You are doing a tempo session. ERG Mode will “lock in” the trainer at your tempo range so you can stay at a constant tempo power output. It gathers this data from FTP number you have set in your app(s). It is compatible/available in most smart trainers or apps (i.e. Wahoo app, Zwift, Garmin, Training Peaks Virtual, etc.)

Pros & Cons of ERG Mode.

Pros:

• Using this mode allows you to focus only on producing the correct power while not focusing on anything else. 

• Using ERG can keep you honest in your intervals.

Cons:

• It can limit the power you can output if you are feeling good, or if you are feeling bad and your cadence drops, you can go into the “death spiral”.

• Sometimes ERG mode can feel harder than the effort actually is because it locks in and doesn’t allow you the flexibility to move about your range.

When to use ERG Mode.

Keep in mind, these are my personal preferences. Everyone will feel a bit differently about this, but this is what works best for me. I like to use ERG Mode for very specific sessions or times within a session.

• Warm Up - I’ll put ERG on to allow my body to warm up gently as it will slowly raise the power.

• Zone 2 Work - If I need to get in some solid endurance work, I’ll put ERG on and “zone out” a little bit.

• Recovery Intervals - I put ERG on here to ensure I’m riding easy enough after a hard interval.

• Cool Down - to allow the body to gently warm down from the work.

When not to use ERG Mode.

Again, these are my personal preferences. I don’t love using ERG for most workouts you’ll find! I like to be able to push and manage my own power and mentally focus on each interval. In part I think this helps when it’s time to go outdoors and you are in a group ride or race. The ability to focus and push without aid is important to hone and have in your back pocket.

• Tempo/Threshold Sets - I like the ability to move around within my zones, so I take ERG off. You can use ERG for these, but you must stay focused!

• VO2 - The trainer can lag or send you into a death spiral on these, so I like to go non-ERG for high power sessions.

• Sprint Work – The efforts are very short and again, the trainer may lag in getting the power up, then send you into a death spiral. Plus, on sprint work you don’t really want a power limit.

ERG can have its place in training, but I encourage you not to rely on it for every session. Think about using it like a tool in your toolbox. It can be helpful sometimes, but you aren’t going to reach for it every time you need your toolbox. Use it to familiarize yourself with how certain power outputs should feel, then try to hold it without help. Use it when you aren’t supposed to push, and you have a tendency to overdo it on those days!

-Happy Training!