Updated: Aug 2, 2019
Don't let the description fool you. In fact, despite the term "easy", these training sessions are anything but easy. Most athletes struggle to keep their easy runs at the correct intensity - below the ventilatory threshold. The "no pain, no gain" mentality of sport has infiltrated the realm of endurance training. Many assume that if they are not pushing the effort they are not improving. Extensive research on the subject, however, indicates the exact opposite. To improve one's ENDURANCE, one must perform the vast majority of ones training at an aerobic effort.
EASY RUNS are not slow slogs, but rather focused efforts, "deep work," "deliberate practice." To maximize these efforts, athletes can focus on how they feel, what their form looks and feels like, as well as other metrics that many modern technologies measure - pace, heart rate, cadence, power, etc. and how those metrics correspond with how one feels. For more information on running by feel, please read "Running by Effort."
Easy runs are also good opportunities to run on soft surfaces or introduce a new stimulus like ascending, descending or running on slightly more technical terrain with roots and rocks because the intensity is low enough that the new stimuli will not overload the athlete, but rather increase engagement and gradually prepare the body and mind for more intense efforts with the new stimuli.
We color code EASY RUNS in blue within the training plans that we design in Final Surge. Blue represents fully oxygenated blood because easy runs are entirely aerobic.
If using the TALK TEST to gage effort, EASY RUNS should be "conversational."
If using Relative Perceived Exertion to measure effort, EASY RUNS should fall around 5 on an RPE scale of 1-10.
If using HEART RATE to measure effort, EASY RUNS should fall in Zone 2 out of 5.
THE 80/20 RULE
When researchers studied the training of the best endurance athletes in the world (runners, nordic skiers, cyclists, swimmers, rowers, triathletes, etc.) they found that between 80 and 90% of their training falls at or below the first ventilatory threshold - the point at which the breathing rate abruptly deepens.
Stephen Seiler, an American physiologist based in Norway, is the scientist responsible for much of these findings among top endurance athletes. Matt Fitzgerald has written extensively about this research in 80/20 Running: Run Stronger and Race Faster by Training Slower.
If the book it too intimidating, Fitzgerald succinctly summarized these findings in a Runner's World article entitled, "Train at the Right Intensity Ratio."
If the best endurance athletes in the world do 80-90% of their training at an "easy" effort, below the ventilatory threshold, it stands to reason that the rest of us should too. While we may not be running as much or at the same pace, we can certainly benefit by applying these principles to our own training.
Interestingly, however, many aspiring runners assume that because they aren't doing as much training volume as their elite counterparts they have to make up for their lower training volume by running at higher intensities. Fortunately, Seiler and others have already done the research comparing groups who do 80% of their training at or below the first ventilatory threshold and other groups who do 60% or less. The results were staggering. Those who performed 80% of more of their training at a low intensity improved. Those who trained at a low intensity 60% of the time stagnated and often underperformed.
CHUNKING YOUR TRAINING
Not only should the majority of training fall below the ventilatory threshold, according to Anders Ericsson whose research formed the foundation for the best selling book Outliers: The Story of Success, the majority of these training sessions should not exceed 90 minutes. In fact, for optimal results, most practice should be "chunked" into short, manageable 60-90 minute training sessions.