Some key points on heart rate training from Coach Jeff Z

On Tuesday, March 14, Coach Jeff Zahavich gave us a talk on heart rate-based training as it relates to distance running and race preparation. Here are some key takeaway points from his talk:

  • To train by heart rate means that during training, you try to keep your heart rate within a certain range of beats per minute, with the range depending on the type of workout you are doing. These ranges are called zones and in most cases a 5-zone model is used.
  • The most common approach used to determine heart rate zones is to start with determining your maximum heart rate using the formula ‘220 minus your age’.  However, THIS DOES NOT WORK.
  • As you increase training intensity, heart rate tends to increase at a linear rate, whereas the amount of lactate in your blood increases in an exponential fashion.  Knowing what your heart rate is with different levels of lactate in your blood allows for optimal heart rate zones to be determined.
  • When you are using your aerobic system (slower steady running) you burn fat as a main fuel source and the level of blood lactate in your system stays below 2 millimoles per litre (mmol/L).  When you are using your anaerobic system (higher intensity or speed bursts) you burn carbohydrates as a fuel source and the level of blood lactate in your system goes above 4 mmol/L.
  • Training zones are best determined by assessing the level of lactate in your blood and recording what your heart rate is with different blood lactate levels.  Your body is capable of easily flushing out blood lactate when it stays below 2 mmol/L, allowing you to exercise at this rate for long duration.  Heart rate zones 1 and 2 are in this range.
  • When your blood lactate levels are above 2 mmol/L but below 4 mmol/L, you are using a combination of fat and carbohydrates as fuel.  Running in this range is too fast to make improvements to your aerobic system, but too slow to make improvements to your anaerobic system.  This is zone 3, also called the junk zone.
  • Mainly you will want to avoid training in zone 3. It is too fast to sustain for long period while holding good form, and thus you won’t be able to use it to build a good Aerobic base like you can while training in zone 2. By spending too much time in zone 3 your risk of injury is disproportionately higher than your ability to actually gain speed.
  • Zone 3 should not totally be avoided. Pushing yourself during a longer race such as a half marathon is an ideal time to be running in zone 3.  After all, it is a race.
  • Zone 4, where blood lactate is above 4 mmol/L, is tempo run or 10k race speed.  Zone 5 is for shorter distance racing and interval training.
  • The best way to determine heart rate zones is to have a blood lactate threshold test. There are other methods, such as determining maximum heart rate during a 5k race or 20-30 minute high intensity run, but these other methods are not as accurate.
  • Improving your running economy is to improve running performance by either a) running faster for the same level of effort, or b) running at the same speed but at a reduced effort. Basically, if speed relative to effort is improving, you are getting better.
  • By doing roughly 80% of your training in zones 1 and 2 and 20% of your training in zones 4 and 5, you will improve your running economy.  It is common to see runners taking this approach realize dramatic improvements in running performance.

Ultimately training by heart rate is all about getting faster while limiting your risk of injury. This is achieved by training at proper effort levels within your own ability instead of running at an arbitrary pace including paces that may be very far out of your current reach.  This is where you put yourself at highest risk of injury.

Coach Jeff has offered a discount for those who attended the March 14 talk as well as a further price reduction if two people schedule tests at the same time. The testing process takes about 2-hours per test or 3-hours (ish) for two, as one warms-up while the other is being tested.  If you are a BLT Runners member, check out our Facebook group to get more information on the discounted test rate.