Function Threshold Training Pace

What is Threshold?

Lactate Threshold Pace, Heart Rate or Power all refer to the maximum effort you’re able to maintain while your body can still remove the lactate acid being used by the muscles. For most trained athletes this is similar to the maximum effort they can maintain for an hour. Going above this threshold effort will result in a “burn” in the muscles and, after a few minutes, require stopping or slowing in order for the body to clear the lactate acid. As endurance athletes, we want to go as fast as we can for as long as we can. Therefore staying under or right at the lactate threshold allows us to go hard, but not so hard that we have to stop.

Lactate Threshold (LT) is also referred to simply as threshold. Lactate Threshold Power is also referred to as functional threshold power (FTP).

Why is Threshold Important?

Unlike VO2 max, which relies largely on an individual’s predisposed physiological characteristics such as lung capacity and body mass, lactate threshold can be improved consistently through training. Training below and above threshold will improve the body’s ability to clear lactate acid as well as tolerate higher concentrations of lactate acid.

As you gain fitness, your threshold increases. Your threshold is the basis around which your training or power zones are established – they are determined as a percentage of your threshold.

How is Threshold Determined?

Lab testing: To determine your threshold power, pace or heart rate you can go to a lab and do a graded test where blood or oxygen exchange samples are taken to determine the effort when you’re no longer able to clear more acid than you’re producing.

Field Testing: Without access to a lab, the next most accurate test is a 1-hour steady effort . If doing a maximal 60-minute test is not possible, an athlete can do shorter, maximal tests and extrapolate their threshold. For example, Joe Friel/Training Peaks recommends an athlete exercise alone and hard for 30 minutes, and use the average pace and or Stroke Rate for the last 20 minutes as your lactate threshold. Such methods of “field testing” may not be as accurate as lab testing but will still provide a sound estimation to base training zones off of, as well as measure fitness improvements over the season.

Building Stamina for Endurance Events

Stamina in endurance sports is the ability (both physically and mentally) to keep performing for a long period of time. All endurance sports require stamina, although some—such as Molokai to Oahu Paddle Board race, Catalina Classic , and long endurance events over 3 hours—require more stamina than others. Developing peak physical condition results in endurance athletes having a high degree of stamina because their hearts, lungs, and muscles all function at a high level of efficiency

Stamina Defined Stamina: a measure of resistance to fatigue during prolonged-duration, moderate-intensity (i.e., sub-FTP) exercise. Units are percent of maximum, i.e., 0-100%, although most individuals will fall in the 75 to 85 percent range.


Physiologically, FTPower is most related to stamina. The introduction of at least 3 to 5 workouts per training macrocycle (3 to 4 weeks) focused specifically on raising threshold performance will pay dividends in the development of stamina. These workouts should focus on training intensities in the RPE 5-6 and Zone 3 to 4 just below the FTPace. This allows an athlete to push threshold up from below, increasing such threshold while still focusing on aerobic efforts.


We can establish what our Functional Maximum Stroke per minute FMSPM is by doing a simple field test. By using a % of the FMSPM that matches with the 5 different Training Zones and doing Interval training sessions the trainers can easily monitor the intensity through out the sessions.

Combine this information with the Field test for Threshold Power we can establish that by retesting every 4 to 6 weeks and monitor increases in Pace/speed we will progressively building Stamina.

So training at these % of FMSPM also correlates very closely to using (FTP) Functional Threshold power which falls in between 75%-85% of our FMSPM and by using RPE, Stroke Rates and Paddling Pace we can keep close eye on our training intensities and progression in most training conditions.

Once we have established what our FTP is and aware of at RPE at which it feels, we can work on building the Stamina required to paddling faster for longer in endurance events in all conditions.