Determining your Heart Rate Zones
An Easy Way to Self-Test
There are several ways to determine your Heart Rate Training Zones, some of which are more accurate than others. Testing in a lab where blood samples are drawn and measured for Lactic Acid is very accurate, but expensive. Subtracting your age from 220 (224 for women), or using the similar (Karvonen) formula is easy, but can be off by 15- 20%. And your maximum heart rate has nothing to do with determining your training zones. Your training zones are developed around your “Lactate Threshold”, or that point at which lactic acid begins to accumulate in the blood at an increasing rate. Here’s a method for calculating your lactate threshold heart rate (LTHR) for cycling, running and swimming that is a self test and which is reasonably accurate.

During a training program, you should test for your LTHR early in your training program and at intervals of 4 – 6 weeks after that to adjust your zones for improvements in fitness. It is important to replicate as many conditions as possible for each test (e.g. time of day, nutrition prior to test, equipment used, course used, weather conditions, fatigue level, etc.). Variations in these factors will impact your test results!

Cycling LTHR TT Test
Long warm-up. Then ride a 30 minute time trial all out (at as high of an effort as you can maintain for the 30 minute interval). Race effort. Use a flat, out and back course without traffic lights or other stops, or do on a trainer. 10 minutes into the time trial punch the lap button on your heart rate monitor. Afterwards, record your average heart rate for the last 20 minutes. Also record distance covered or average speed. An alternate to this would be to record your average heart rate for a 40 km time trial under full race conditions.

Bike Heart Rate Zones
Zone 1 Less than 81% of LTHR
Zone 2 81% to 89% of LTHR
Zone 3 90% to 93% of LTHR
Zone 4 94% to 99% of LTHR
Zone 5a 100% to 102% of LTHR
Zone 5b 103% to 106% of LTHR
Zone 5c More than 106% of LTHR

Running LTHR Test

Warm up well. Then run a 30 minute time trial on flat course/track. Punch HR monitor ‘lap’ button 10 minutes into Time Trial. Average heart rate for last 20 minutes predicts Lactate threshold heart rate (LTHR). An alternate would be to record your average heart rate for a 10 km road race at your fastest effort.

Run Heart Rate Zones
Zone 1 Less than 85% of LTHR
Zone 2 85% to 89% of LTHR
Zone 3 90% to 94% of LTHR
Zone 4 95% to 99% of LTHR
Zone 5a 100% to 102% of LTHR
Zone 5b 103% to 106% of LTHR
Zone 5c More than 106% of LTHR

Swimming LTHR Test

In swimming, we refer to “T-Pace” quite often to prescribe intensities. Your T-Pace is the pacer per 100 yards that you can swim for a continuous 1,000 yards. This also predicts your LTHR. For example, we might say to swim 500 in T-pace +5. If your T-Pace were 1:40/100, than your T-Pace + 5 would be to swim that 500 yards at the pace of 1:45 per 100 yards. You will be able to get a feel for this with experience, so estimate how the intensity feels each time you swim so that you can be familiar with your zones by how an intensity feels (in other words, you are using your rating of perceive exertion- rpe).

To determine T-Pace, swim a brief warm up set. After your warm up, swim a continuous 1,000 yards at a constant pace. Try not to go out so hard that you fade early in the swim, but go out as hard as you can and maintain that pace for the entire duration. Take your pulse/HR at the end of the swim and record both your HR and your time divided by 10. That will be your T-Pace.