This DIY Anaerobic Threshold test will help you determine your Anaerobic Threshold (AnT) heart rate, which will be useful when it comes to monitoring your effort and training load.
WARNING: This test is hard! Working at your anaerobic threshold means you’ll be working at the hardest effort you could sustain for maximum 60 minutes. For the runners in the crowd, think 10K race pace.
Plan to do this test when you are well-rested, ideally at least three days after any hard efforts. It can be done either on a steep treadmill (15 percent), a steep uphill, or, if you are a well-trained runner, you can do it on the flats.
The test portion (excluding warm-up) will take between 30 and 60 minutes.
If you are new to training, choose a 30-minute test length. If you are very well-trained with many years of aerobic training under your belt, you can use a 60-minute test length. You can also use a 45-minute test length.
You will want to be well-fueled prior to testing. Make sure you ate your most recent meal at least 120 minutes pre-testing and ideally top up with a light carbohydrate-focused snack of about 100 calories within 30-45 minutes of starting the test.
Anaerobic Threshold Test Step-by-Step Guide
- Make sure you have a heart rate monitor (chest strap or arm band) that is working and ready to record the whole workout.
- Do a 15-minute warm-up at or below your Aerobic Threshold (AeT) or until you break a sweat. Ease into this warm-up so that your body is ready for the test. If you typically need a little longer to warm up, take the time you need, but typically 15-20 minutes is all you need.
- After you’ve warmed up, it’s time to start the AnT test. Hit the lap button on your watch, and then run/hike as hard as you can sustain for the full 30 minutes (or 45 or 60 minutes).
- Pace yourself so that you don’t blow up 5 minutes into the test- the key is to sustain this hard effort for 30-60 minutes.
- Note your average heart rate for the 30-60 minute test. This will be your AnT heart rate.
- If you are unable to sustain the hard effort for 30 minutes, try again in a few days. If this seems just too hard for you right now, that might just mean that you need more time focussed on building your aerobic base- try again in 3-4 weeks.
The 10 Percent Test
Once you have your AnT heart rate, subtract your previously determined AeT heart rate from it. Example: AnT heart rate from this test = 165. AeT heart rate from that test = 152. 165–152 = 13.
Ten percent of 165 = 16.5. Using the above example, we end up with 13, which represents less than 10 percent.
If the difference is 10 percent or less than the AnT heart rate, it could be helpful for you to reduce the amount of your Z2 training and focus more on Z1 for your aerobic base training.
If the spread between your AeT and AnT is greater than 10 percent, then do all of your aerobic base training in Z2. We recommend repeating the AeT test after 4 more weeks of training if this is the case. As your aerobic base improves and your AeT heart rate and pace move upward, you can then decrease the volume of Z2 work.
Notes
It can be useful to test both AeT and AnT near the beginning of a new training season, and it may be useful to retest periodically. If you are using TrainingPeaks to record and analyze your training, which we recommend, these two numbers are important markers that allow the algorithms to accurately estimate your Training Stress Score (TSS), Chronic Training Load (CTL), and other useful measures available on that platform. Your anaerobic threshold heart rate is the number you will plug into TrainingPeaks as your Threshold HR, which is the basis of TrainingPeaks scores.
For a full rundown of Uphill Athlete’s recommended methods for determining AeT and AnT, read “Aerobic Self-Assessment for Mountain Athletes.”