by Tim Curry, MS ACSM-RCEP

Training Zones and Injuries

When was the last time you or someone you were riding with crashed during a ride? Crashes during the back half of the ride are common but are something we can address through smart application of training intensity. Let’s discuss what we can do for ourselves and the athletes we coach. 

What’s the Connection?

First, let's acknowledge several facts that contribute to injuries based on the current scientific literature:

  • In high school sports, 50-60% of all injuries occur in the second half of practice or competitions. 1 

  • In NICA the majority of crashes occur in the back half of practices, with 60% happening during a downhill descent. 2 

While there are many factors that contribute to a crash there’s one common theme across the research: fatigue. When athletes are fatigued they are much more likely to make mistakes that lead to injuries. In sports such as mountain biking athletes regularly encounter scenarios (ex. High speeds, and quick technical descents) where there is almost no margin for error and any mistake can result in serious injury. Fortunately, reducing athlete fatigue levels is a simple solution to help reduce the risk of injury. This surprisingly simple and meaningful approach is as easy as implementing planning and management of training ride intensity. 

Training Intensity Tools

There’s a plethora of potential tools available for measuring training intensity, with varying levels of expense. For this article, we will focus on two free, simple-to-use tools that can be applied to any sport at any time, and are supported heavily by scientific research. These tools are Rating of Perceived Exertion (RPE) and the Talk Test (TT). Let's look at how to use each one below:

RPE - At the most basic level this is a subjective measurement of how hard you feel you are working in the moment. You‘ll typically see two scales for RPE ranging from 6-20 or 0-10; each of these was created by the same researcher (with fascinating backstories too extensive to explore here). For our purposes, we recommend using the 0-10 modified Borg scale shown below. To use this scale:

  • First - Explain to your athletes that the purpose of this scale is to allow them to judge how hard they are working at any point in time. This is not a test! It’s important they try to be as honest and objective as possible (i.e. this is not an ego contest!). 
  • Second - Show them the chart and explain the scale. The words on the right side are there to help judge how hard you are working. A zero is sitting in a chair doing nothing. (As soon as you start riding you are above a zero.) A ten is the hardest you think you are able to go.
  • Third - If possible, provide individual charts to each athlete. Placing the chart on their top tube is a great spot for them to easily refer to it during a ride. Having the chart available for reference is the best way to learn and apply RPE correctly. (We will have a pocket chart available to download, and are working on having top-tube chart stickers available for purchase in the future.)
  • Fourth - Set up some “calibration” rides where the entire group is asked to ride at certain RPE ranges during the ride. This will help your athletes understand what each RPE level actually feels like while riding. Expect that they will go too hard or too easy on the first few attempts. An example of a calibration ride breakdown could be:
    • 10 min at RPE 1-2
    • 5 min RPE 3-5
    • 5 min RPE 1-2
    • 4 min RPE 6-8
    • 4 min RPE 1-2
    • 1 min RPE 9-10

Make sure there is rest interspaced following the harder rounds to ensure your athletes don’t become overly fatigued. On these days it’s important to consider your route. It’s ideal to complete harder and shorter efforts during a hill climb where speed is limited; DO NOT do these efforts while going downhill!

TT - The talk test is even easier and can be used by a coach to judge how hard an athlete is working at any time! It is built around the fact that our breathing rate, and subsequently our speaking ability, is tied to what is happening metabolically in our cells. To do this test:

  • Have them speak for 15 seconds. Now imagine that during the talk test, you were on a phone call (no video!) working with peers on a project. Based on your speech, where would you fall on this scale:
  • Level 1 - My peers would not know I was working out 

  • Level 2 - They would know I was active but I could still easily be a productive member of the team 

  • Level 3 - They would know I was active and I would not be a very productive member 

  • Level 4 - I would not be very productive and it would be difficult to keep track of some or many details 

  • Level 5 - I could not keep track of the project and would not be helpful at all 

With some practice, athletes can easily apply the talk test very quickly to assess themselves. You can also ask open-ended questions during a ride and listen to the athlete's speaking quality to assess which zone they are actively riding in!

Controlling Fatigue 

Now that you know how to assess an athlete’s intensity level you can begin to compare where your riders are currently to where you want them to be for the ride plan. The chart below outlines five basic zones along with the RPE and TT range(s) for each, as well as the expected riding time. 



Talk Test (TT)

Riding Time

1 - Active Recovery


Level 1

20-60 min

2 - Long Endurance


Level 2

1-3+ hrs

3 - Medium Endurance


Level 3

Up to 60-90 min

4 - Threshold


Level 4

30-60 min

5 - Suprathreshold (VO2max)


Level 5

<5-10 min

The higher the zone the faster fatigue builds which, in turn, requires more recovery time. By designating a training intensity zone for parts of or the entirety of a ride, you can help riders manage how hard they are working. This allows them to control their fatigue and reduce injury risk! For instance, let's say we’re doing a two-hour ride where the first hour is uphill followed by a longer 20 min downhill, then a mix of rolling hills back to the finish. A ride of this length is too long to stay sustain a Zone 4 or above effort, and even in Zone 3 it would be very fatiguing. We know that downhills are where the majority of injuries occur, so we should aim for maintaining our effort in Zone 2 for the entire first climb. This would allow athletes to minimize fatigue at the start of the descent. Then for the rolling hills at the end, we could stay in Zone 2 or perhaps add in a little more intensity with some Zone 3 or 4 work on some of the hills, when we can ensure that we can manage risk appropriately. 

Team Application

It is very common and even expected that within a ride group, there will be a range of fitness levels, so how should you establish intensity for the entire group. If we set it based on keeping the fittest riders in the appropriate zone for them then the majority of the group may be well above their target zone, thus accruing large amounts of fatigue. Alternately, if we were to select an average zone for the entire group then we will still likely have riders working far harder than planned. It may not be the most exciting solution, but the answer is to set the pace based on the appropriate zone for the least fit rider. This may not be optimized for every rider but this is a group ride, not an individualized training session. As we know, our focus is on safety first and this is the best way to achieve that goal while still creating a challenge for our athletes. 

Intensity Is Just The Beginning…

You likely have asked “What about hydration? Food? Weather? Etc” and you’d be correct to consider these factors! Managing fatigue involves many moving parts and should be approached holistically. Learn more with these other great articles: Sports NutritionRace Day NutritionNutrition and High School AthletesWhen Water Becomes Dangerous, and Training in the Heat. For more information and to learn how to apply these concepts to better help your athletes (and yourself!) while receiving CEUs, don’t forget to check out our recommended courses below!

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1 - Nagle, K., Johnson, B., Brou, L., Landman, T., Sochanska, A., & Comstock, R. (2017). Timing of Lower Extremity Injuries in Competition and Practice in High School Sports. Sports Health, 9(3), 238-246. doi:10.1177/1941738116685704

2 - National Interscholastic Cycling Association. (2021). The National Interscholastic Cycling Association Safety Report 2021. Retrieved from