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What is TrainerRoad's Fatigue Detection?

TrainerRoad monitors your training to help prevent long-term fatigue and unproductive workouts. Our built in fatigue detection tells you when you might be overdoing it with Avoid Intensity days and Rest recommended days on your TrainerRoad Calendar. 

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What are Avoid Intensity Days?

Days on your TrainerRoad Calendar will change color in response to accumulated training stress. If you are in a potentially “unproductive” range it will display an Avoid Intensity day on your Calendar. If you see a yellow highlight on your Calendar and a yellow caution sign it means we recommend slowing things down.

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If you have a workout scheduled on an Avoid Intensity day TrainerRoad will adjust your scheduled workout to an Endurance workout. You will know that your workout has been adjusted because the previously planned workout will be listed behind the newly scheduled workout.

Avoid Intensity days aren’t necessarily a bad thing! If you’re nearing the end of a challenging training block, or pushing your boundaries multiple days in a row (like at a training camp), you might see a few yellow highlights appear on your calendar.

What are Rest Recommended Days?

If you’re pushing it into long-term fatigue territory, you’ll see a Rest Recommended day on your Calendar. Rest Recommended days will display red highlights and a warning sign on your Calendar. If you have a workout scheduled on a Rest Recommended day your workout will be swapped for a rest day. You will know that your scheduled workout has been swapped because a rest day will be displayed and the previously scheduled workout will be listed in behind it. 

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If you try to schedule a workout on a Rest Recommended day you will be advised to keep your day open and focus on rest instead. You might see red days after big training rides, a hard race, or multiple days of challenging riding.

A Rest Recommended day is a Warning sign. These days indicate that you’ve likely overdone it and adding additional stress onto this day won’t be benefitting you. When a rest day pops up on your Calendar we recommend taking the day off from all forms of training stress and focusing on recovery.

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How Does it Work?

TrainerRoad uses your data from all indoor and outdoor training sessions, as well as other metrics specific to you, to monitor your training. As you train, recover, and get more fit, the amount of stress you can productively manage changes.

You don’t need to do anything to enable the fatigue detection! Train as you normally would, following a TrainerRoad plan, TrainNow workouts, and training outside. If a workout pushes you over the boundary of productive stress, you may see a yellow or red highlight show on your TrainerRoad Calendar for the following day. If those days have workouts scheduled, you’ll be offered a suggestion to an easier ride or a full Rest Day to prevent long-term fatigue.

Can I Adjust How Cautious Fatigue Detection Is?

Yes! You can directly adjust how conservative or aggressive TrainerRoad is when it comes to recommending rest. You can do this by adjusting your training approach. This can be done for your entire training approach or by zone. To learn more about making adjustments to your training approach read: How to Adjust Training Approach Overall and by Zone

What Should I Do on Rest Days?

Whenever possible, we recommend refraining from any type of physical exercise on rest days. We don’t recommend using these days to incorporate additional training activities like recovery cycling activities, strength training, or other forms of cross-training.

For further reading on rest and how to maximize recovery we recommend checking out these Blog Posts on recovery from the TrainerRoad Blog:

  1. Rest Week Nutrition: What to Eat to Recover
  2. Why Rest, Recovery, and Tapering are Necessary to Get Faster
  3. The Complete Recovery Week Guide for Cyclists
  4. Recovery: The Elements of Getting Faster

Frequently Asked Questions:

Are outside activities considered by this tool?

Yes! TrainerRoad considers all outside workout files imported into TrainerRoad.

What kind of activities does the fatigue monitor take into account?

TrainerRoad considers all activities on your Calendar. 

Can I decline changes prompted by red and yellow days?

Just like any other recommendation that appears on your Calendar, you can decline any fatigue related adjustments. In most cases, we strongly recommend accepting these suggested changes though. TrainerRoad's AI is aiming to prevent long term fatigue and make you faster in the future

Are these days bad?

Yellow and Red days aren't necessarily a bad thing! In fact, it's normal to see Yellow and Red days pop up on your Calendar after pushing your limits with a hard race, a tough workout, or several big training days.

Your Red and Yellow Days can become troublesome or "bad" if you are consistently training through them and ignoring TrainerRoad's suggestions. To help prevent long-term fatigue and keep your training on track we recommend accepting these suggestions whenever possible. 

Do I need to be following a training plan to get fatigue detections?

No! TrainerRoad will notify you when you have Yellow and Red days even if you are not following a TrainerRoad training plan.

Am I not training hard enough if I never get Avoid Intensity days?

Not necessarily! If you are never seeing Yellow days on your Calendar, this could be an indication that you are managing your fatigue well and recovering from your training quickly. If you are never seeing a Yellow day on your Calendar and you feel you have more time and energy to dedicate to your training you might be in a good position to increase your training volume, though.

How long do I need to rest after a Rest Recommended day?

A day fully off the bike should be enough to ease back into your training. After really large efforts, you may see multiple red days on your Calendar followed by a Yellow day. In these cases, you want to take extra recovery and ease back into your training.

What if I have a race on one of these days? Should I skip it?

These aren’t necessarily a bad thing. Rather red and yellow days are meant to remind you when you are reaching or going down a path that could lead to long-term fatigue. You can still feel good and have a great race or a solid training day on a red day - just make sure you get the necessary recovery time after! 

If you find that you’re getting into the Yellow or Red before an A events though, you should prioritize the extra rest TrainerRoad recommends to ensure you are getting enough prior to your event.

What if I get Rest Recommended during a stage race?

Keep going! Stage races and training camps are situations where you’re likely going to accrue a lot of training stress which will yield yellow and maybe even red days on your Calendar. Just make sure you take the time to recover properly once it’s wrapped up.

Will these appear in the desktop and mobile apps?

Yes! You’ll see red and yellow days in the mobile and desktop apps.

Do I have to use TrainerRoad inside for fatigue management to work?

Nope! TrainerRoad works even if you only ride outside.

Do my post-workout survey responses influence fatigue detection?

Yes, TrainerRoad considers your post-workout surveys. Make sure to answer your post-workout RPE survey.

Do my outside activities need power data to be considered by TrainerRoad?

Nope! Activities that only have Heart Rate data will count if you use TrainerRoad’s Heart Rate TSS Estimation.

Following my plan made my current training day Rest Recommended. Is everything working as it should be?

If you’re following a TrainerRoad plan exactly as prescribed and getting into the red, that may indicate that you’ve selected too high of a plan volume. If you find yourself in a situation like this we recommend lowering your plan volume to prevent long-term fatigue.

TrainerRoad wants to remove a key workout. Should I move the workout to another day?

If a Rest Recommended day pops up on the same day as a workout we recommend accepting the Rest Day and focusing on your recovery. Rest days are key workouts in their own regard! Furthermore, TrainerRoad will make any necessary adjustments to your upcoming weeks of training to make sure you get the key training sessions that you need.

I trained through an Avoid Intensity or Rest Recommended day. Shouldn’t this make tomorrow a yellow or Rest Recommended day too?

Not necessarily! Training on a yellow or red day doesn’t automatically yield another red or yellow day in your Calendar. 

I feel like I need rest but there isn't an Avoid Intensity or Rest Recommended day today. What should I do?

Just because you are not seeing a yellow or red day doesn’t mean you don’t need rest! Fluctuating changes in personal stress, illness, or a bad night's rest  might require you take an easy day outside of TrainerRoad's recommendations.

If you need to take a rest day on a non red or yellow day go ahead and skip your workout and TrainerRoad AI will make any necessary adjustments.

I accepted a rest day recommendation and now I want that workout back. Can I undo it?

There is no way to reverse recommendations that you have already accepted. If you’d like to recover a workout that was replaced by a rest day or an endurance workout and you can’t remember what workout was on your Calendar reach out to support@trainerroad.com.

What should I do when an Avoid Intensity day appears on my Calendar?

When a yellow day appears on your Calendar, and you have nothing scheduled we recommend taking the day off. If a yellow day appears when you have a workout on your Calendar you will be prompted to adjust your scheduled workout to a workout that allows for a bit more rest than your scheduled workout.

What should I do when a Rest Recommended day appears on my Calendar?

When a red day appears on your Calendar we recommend taking a rest day and refraining from as much physical activity as you can.

What happens to Runs and Swims on Avoid Intensity and Rest Recommended Days?

Swims and runs will be adjusted on these days too! If you have a run or a swim scheduled on an avoid intensity day, TrainerRoad will suggest that you do an easier swim or run on that day. If you have swim or a run on a Rest Day, TrainerRoad will suggest swapping any workouts scheduled on this day for a rest day.

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