Friday, July 17, 2015

Threshold Heart Rate – Part 2

Last week we looked at why training with heart rate is important. A seeming simple concept can be very complex and confusing and if not done correctly, can yield less than satisfactory training results. After all your heart is the machine that drives your endurance performance with the precision of race car. You need to get your heart rate training dialed in correctly to see the improvement you are seeking.

Head coach and owner of QT2 Systems, Jesse Kroplenicki utilizes the following formula to determine your Threshold heart rate (TH).

Bike Test - Utilizing you bike on a stationary trainer
Primary: After a warm-up, complete an 8 minute all out time trial on your bike (pushing as big a gear as you can) recording average heart rate utilizing a heart rate monitor such as Garmin 920XT

TH heart rate is typically about 8 beats below the average heart rate for this test.

Cross Check: This method requires no immediate testing if you already have the data:
Take the highest HR you have ever seen on the bike (within the last 4 years) and subtract your resting HR from that number. Then multiple that “heart rate reserve” by 0.81 and add back your resting to that number.

Take the average of these two methods or choose one versus the other based on how accurate the data input were to each.

Running Test

Primary: After determining your bike TH heart rate, you can then offset it to your run TH heart rate by adding 6-14 beats. Almost every athlete I have worked with falls within this range with most being right around 10. So, first add 10 and then make the following adjustments to the number you get:
If you are a woman shorter than 5’-3” subtract 2
If you are a woman taller than 5’-9” add 4
If you are a male shorter than 5’-6” subtract 2
If you are a male taller than 6’-0” add 4

Cross Check: After a determining your TH above, confirm your running estimate by completing an open running road race while recording average heart rate. A great estimate of threshold from an open road race is:
Average 5K heart rate minus 15 beats
Average 10K heart rate minus 10 beats
Average half marathon heart rate minus 5 beats

Take the average of these two methods or choose one versus the other based on how accurate the data input was to each. After two open road races confirm the offset, its likely best to use that number and disregard the primary offset above if it suggests something different.

I always like to cross check TH heart rate with a few different methods since this is the number a lot of an athlete’s training will be based on! The bottom line is that most athletes should spend more than 70% of their time at less than 86% of this number with almost 100% during the early season. Next week I will look at how to calculate the various hear rate training zone and how to apply them for specific purposes.