Lactate Threshold Trianing

One of the most common ways to gauge lactate threshold training intensity is to monitor heart rate. While, a very quick and simple method is to simply assume your lactate threshold will occur at 85-90% of your maximum heart rate, this method lacks accuracy and reliability for many athletes. If you do want to determine training intensity this way, use the Karvonen formula rather than simply deducting your age from 220.

http://www.sport-fitness-advisor.com/heart-rate-reserve.html
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more reliable method is to determine your heart rate at the lactate threshold and then to train at this heart rate intensity. This is by no means flawless however, especially as heart rate often tends to rise slowly over prolonged exercise periods without increases in intensity a phenomenon known as cardiac drift.

Cyclists can use a power meter to determine the work rate at lactate threshold and thus a suitable intensity for lactate threshold training sessions.

Here is a typical interval lactate threshold training session:

Interval Training Session
Frequency 2x week
Intensity 95-105% LT*
No. intervals 3-5
Interval time 10mins
Rest intervals 2-3mins

Continuous Training Session
Frequency 2x week
Intensity 95-105% LT
Time 20-30mins