Understanding Lactate Threshold Heart Rate Training
Marty Gaal, CSCS
concepts for improvement in endurance racing and training involve:
- Increasing your aerobic endurance
- Improving your lactate threshold heart rate (LTHR)
The first is accomplished by completing workouts involving aerobic exercises
(swimming, biking, running, rowing, cross-country skiing, and so on) at an easy
to moderate effort level. Over time, your ability to continue the
exercise will improve through physiological adaptations to the specific
For example, if you are currently untrained or out of shape, a 30 minute bike
ride may be challenging and near the limit of your ability. If you
go and ride 20-30 minutes three times per week for a few weeks, your body will
adapt by; increasing blood flow to the muscles being used; increasing muscle
size (hypertrophy) and strength; improving blood flow through a process called
capillarization (tiny veins to the muscles); increased mitochondrial density
(aerobic enzymes) in the muscles; and a few other geeky details.
All these result in the ability to use oxygen as the main exercise energy
source more efficiently, meaning you can now ride longer and not be tired at 30
The second, improving lactate threshold, is accomplished by completing easier
training sessions like the above, plus including more challenging workouts that
raise your heart rate.
Lactate threshold is the point in exercise where your body produces more
blood lactate than it can reabsorb (and manage other lactate by-products - look
up "hydrogen & lactate & exercise" if you want
some exciting reading) on a continuous basis. Well trained athletes can
usually continue exercise at just below lactate threshold for about an hour.
Go over lactate threshold though, and that time drops to 5-6 minutes.
For most people,
the lactate threshold is about 20 heart beats per minute above the steady
aerobic threshold. Any aerobic exercise, generally speaking, will help
both points go a bit higher. But there is a point of diminishing returns.
If you don't also include workouts that challenge your system by going just
below to above your current lactate threshold, you will not maximize your ability
in short distance to long distance events.
The secret or goal with lactate threshold training is to raise your threshold
point to as close as possible to your maximum heart rate, and improve your
ability to withstand that discomfort (if it was easy everyone would do it).
If you never do harder workouts, then your lactate threshold will always
remain below your possible maximum lactate threshold.
Raising your lactate threshold point, for the most part, will bring your steady
aerobic threshold point up with it (as the 20 bpm relationship is fairly
So - if you're training for an Ironman, from a specificity standpoint you want
to train that steady aerobic threshold because that is more or less your race
pace. But. You should include some LT training as well to raise that
point a bit higher.
If you're training for a sprint or Olympic distance race, from a specificity
standpoint you want to work more on that 2nd threshold. But. You should include
quite a bit of aerobic steady training as that provides your 'foundation.'
Blah blah blah, how do I find my threshold and what are some workouts ideas!!?
Warm up 15-20 minutes then 30 minutes "race effort". As hard as
you can go for 30 minutes. Take your heart rate average for the last 20
minutes. Bingo. = LTHR.
2 x 20 minutes just below lactate threshold with 5 minutes easy between
5 x 5 minutes at lactate threshold with 3 minutes easy in between
5 x 3 minutes over lactate threshold with 3-5 minutes easy in between
8 x 1 minute well over lactate threshold with 2-3 minutes easy between
2 x 10 to 15 minutes (1 to 2 miles) just below threshold with 5 minutes easy
4 or 5 x 4 minutes (800-1200m) at threshold with 2-3 minutes easy between
5 to 6 x 3 minutes (600-800m) over threshold with 3 minutes easy between
8 x 1 minute over threshold with 1 minute easy between
*generally speaking, running causes more breakdown so total "hard"
training volume should not be more than 10-15% of weekly mileage.
4 x 400s just below threshold with 1-2 minute between each
12 to 16 x 100s at threshold with 10-15 seconds rest between each
8 x 50 over threshold with 30 seconds to 1 minute rest between each
There are plenty of other workouts, but the theme here is:
sub-threshold workouts take 10-25% interval rest
at-threshold workouts take 50-75% interval rest
over-threshold workouts take 100-200% interval rest
In general: advanced athletes can do more repetitions and/or take less rest;
beginner athletes should do less repetitions and take more rest.