Endurance training is quintessential “base training” where you focus on building mileage — or workout duration. Endurance events by definition require the ability to move for long periods of time, necessitating a well-developed aerobic system to supply energy for the duration of your activity.
Endurance training targets both extensive endurance and intensive endurance as you increase the duration of your long runs or workout sessions.
The key workout during this phase is the standard base-training endurance workout in the “conversational” zone — that is, at or below your aerobic threshold (AeT) — to develop your aerobic system. These “conversational” zone endurance workouts involve a continuous effort with durations of 20 minutes up to several hours. The training effect targeted is your body’s ability to better metabolize fat and spare glycogen (stored carbohydrate) as a long duration energy source.
During a “conversational” effort, you should be able to breathe through your nose and hold a back-and-forth conversation with someone running next to you (taking turns to speak). Breathing is moderate and not labored. Once you’ve moved beyond this effort level, you’ve moved beyond your aerobic threshold (AeT).
During endurance training blocks, you will gradually increase the duration of one or more weekly endurance workouts. The duration you work up to will depend on the duration of the event you’re training for. Whereas a 90-minute long run may be sufficient for runners racing half marathons or shorter, marathoners may target long runs of 2-3 hours, and ultrarunners may do long runs that last 6+ hours.
Another key workout during this training phase is the “comfortably hard” tempo workout — also known as, “steady state” or “marathon simulation.” These workouts, which are used to build intensive aerobic endurance and improve lactate tolerance (and to simulate marathon-distance race pace), involve sustained tempo intervals of 20-60 minutes with a 5:1 up to 8:1 work to recovery ratio. Total time at intensity during these workouts can range from 30 minutes to 2 hours. For example, after you’re warmed up, you might do 30 minutes at a “comfortably hard” effort followed by some additional time at a “conversational” effort before warming down, or your workout might involve 2 x 20-minute “comfortably hard” intervals with a 4-minute recovery interval between them.
During a “comfortably hard” effort for these tempo workouts, you should still be able to breathe through your nose, but your ability to talk will be limited to 2-3 sentences at a time. Breathing is deep and labored.
Endurance training might span 8-12+ weeks in your training plan.
Endurance Training: Key Workouts
The key workouts during endurance training, as illustrated below, include endurance workouts and tempo workouts. Recovery workouts are used on days between the key workouts.
Endurance Workouts
Endurance workouts contribute to your aerobic base. During the endurance training phase, you will be increasing the duration of one or more endurance workouts each week — the weekly “long run” for runners. Ultrarunners might use back-to-back long runs — that is, long runs scheduled two days in a row — to achieve greater volume in preparation for longer events. When stacking back-to-back long runs, do the harder/longer run on the first day. The endurance workout in other training phases will remain relatively constant in duration with the exact length depending on your event and goals. The bulk of your training time during any training phase will consist of recovery and endurance workouts.
Conversational Zone:
- Intensity: At or below your aerobic threshold (AeT)
- Heart Rate: 85-89% of lactate threshold heart rate (LTHR)
- Power: 56-75% of functional threshold power (FTPw)
- Pace: 114-129% of functional threshold pace (FTPa)
Total Time at Intensity: 30 minutes to 6+ hours
Interval Time: n/a
Work to Rest Ratio: n/a
How Often: 2-6 workouts per week during all training phases
Purpose: Used more than any other training zone to build the aerobic endurance base, which allows you to better metabolize fat and spare glycogen (stored carbohydrate) as a long duration energy source.
Sample Workout: 90-minute endurance run
Tempo Workouts
Tempo workouts are used sparingly as a bridge to higher intensity threshold work or to simulate marathon-distance race pace. These are steady-state aerobic tempo sessions below your lactate threshold, but above your aerobic threshold (more on these terms). So they are “comfortably hard” to sustain over the duration of the interval, which can range from 20-60 minutes. You can integrate these into an endurance workout or do a tempo workout on its own after an easy warmup and before a warmdown. The progression for these workouts is to increase your time at intensity and then decrease the recovery time between the intensity bouts. You’ll typically want to schedule at least one recovery day between these workouts.
Comfortably Hard (Tempo) Zone:
- Intensity: Above your aerobic threshold (AeT) for sustained durations
- Heart Rate: 90-94% of lactate threshold heart rate (LTHR)
- Power: 76-90% of functional threshold power (FTPw)
- Pace: 106-113% of functional threshold pace (FTPa)
Total Time at Intensity: 30 minutes to 2 hours
Interval Time: 20-60 minutes
Work to Rest Ratio: 5:1 to 8:1
How Often: 2-4 workouts per week during endurance training phase
Purpose: Used sparingly as a bridge to threshold work, to build intensive aerobic endurance and improve lactate tolerance; and to simulate marathon-distance race pace.
Sample Workout: 90-minute endurance run with 30-minute tempo in the middle