When it comes to determining your physiological training zones, the testing protocol you choose matters more than you might think. Let's examine why the popular ramp test or shorter step test might not always give you the complete picture. Here’s how to identify those shortcomings and how muscle oxygen monitoring with Moxy can help solve these challenges.
Ramp Tests vs. Step Tests: The Key Differences
Many times ramp and step tests are used interchangeably for physiological testing. These tests are designed to take someone through exercise intensities starting easy and getting very hard. They allow us as coaches and athletes to get a picture of how our bodies respond to varying degrees of exercise intensities. But there are differences to these two common testing protocols:
Ramp Test: Power or speed increases continuously throughout the test. For cyclists, this typically means an increase of 1 watt every 2-3 seconds (or about 20-30 watts per minute). This type of protocol is typically not used for runners due to the challenge of continuously increasing treadmill speed manually.
Step Test: Power or speed increases in distinct steps, with each step lasting 1-3+ minutes before increasing to the next level. Power or speed generally increases 20-30w or 0.5 kph (0.3 mph), respectively.
Of note, During both types of test, you need to measure some physiological variable (e.g. ventilation, lactate, or SmO2). The response of these variables to different exercise intensities is what allows us to determine training zones.
Typical SmO2 Response and Threshold Identification
During a well-executed test, your muscle oxygen saturation (SmO2) will typically display two distinct "breakpoints" that correspond to your first and second physiological thresholds:
- First Threshold (LT1/VT1/BP1): The point where SmO2 stops rising or shows the first decrease where a subsequent plateau follows.
- Second Threshold (LT2/VT2/BP2): The point where SmO2 begins to continually decrease
These breakpoints help identify your three primary training zones (in a 3-zone model):
- Zone 1: Below first threshold (aerobic/recovery)
- Zone 2: Between first and second threshold (tempo/threshold)
- Zone 3: Above second threshold (high intensity)
These zones then help us determine the internal (heart rate or SmO2) or external (speed or power) intensities to train at to elicit the proper adaptations for the programmed workouts.
However, these idealistic breakpoints don’t always occur for each individual we test.
Common Limitations with Ramp or Short Step Tests
It is possible that someones SmO2 response to increasing load is linear. Meaning that there aren’t any discernible breakpoints. Which can make analysis tricky.
If you have a test where linear SmO2 occurs. There are several factors that can lead to this response:
1. Insufficient Time at Each Intensity
During a ramp test and sometimes a short step test (steps ~1 minute), you may not spend enough time at each intensity for SmO2 to stabilize, resulting in a continuous linear decrease without clear breakpoints. Your muscle needs time to respond metabolically to each workload.
2. Muscle Selection Matters
The muscle you choose to monitor could impact your results:
We recommend placing the Moxy on a primary mover for whatever movement you are doing. Typically for running and cycling this means starting with the vastus lateralis. But other muscles can work if you get a linear response, or no response during the test.
For Cyclists:
- Start with the Vastus Lateralis (side of thigh)
- Consider repositioning to Rectus Femoris (front of thigh) or calf muscles
For Runners:
- Similar to cycling, try monitoring Rectus Femoris or calf muscles if Vastus Lateralis shows unclear results
3. Step Duration Is Critical
Short steps (1 minute or less) sometimes don't allow enough time for SmO2 to stabilize at each intensity level. Consider extending steps to 2-3 minutes to observe more distinct physiological responses.
The Advantage of Using Moxy with Your Testing
Here's the good news: if your initial test shows a linear SmO2 response with no clear breakpoints, you can easily modify your approach without needing to return to a lab:
- Switch to a step test protocol
- Try monitoring a different muscle
- If you are already using a step test, extend the duration of each step
- Retest with these adjustments
Muscle oxygen monitoring with Moxy gives you the flexibility to experiment with different protocols until you find what works best for your physiology, saving you time and money compared to traditional laboratory testing.
Conclusion
While ramp tests and short step tests are popular for their efficiency, they may not provide clear threshold data for everyone. By understanding these limitations and adapting your testing approach with Moxy, you can obtain more accurate physiological training zones to optimize your training and performance.
