Runner Fatigue

Obey Your Stress/Rest Cycle


My first coaching mentor, Guy Avery, used to say “Optimal Stress + Optimal Rest = Optimal Progress.”

This simple phrase is very instructive for the runner and coach. Every training stress (whether an easy run or hard workout) must be followed by an appropriate rest period (recovery with easy running, cross training or no running) in order for the body and mind to optimally increase its fitness.

Guy didn’t invent that equation, of course. As all of us that study training theory learn, the stress/rest cycle evolved primarily from the works of Selye, Yakovlev and Bompa but he certainly had a knack for getting the stress/rest cycle right with his runners and I learned so much from him.

Avery suggests that too many runners and coaches focus only on the “stress” part of the equation – the workouts, the mileage, and the races and often ignore the “rest” component – days off, easy running, cross-training, sleep, nutrition, relaxation. But, in order to advance your fitness to its highest level, you must balance both the stress and the rest. The greater the training or racing stress, then the more rest you will require.

Too many runners “under-rest” after hard training and racing and thus stunt their fitness progress. Avery is a master of this stress/rest cycle concept and proposes that each runner understand and obey the stress/rest cycle in order to avoid injury and perform maximally. It’s a simple concept but one most runners (particularly beginners and young runners) disobey. We get excited about training and train too hard, too soon and too often, resulting in escalating fatigue and injuries.

Another challenge for the runner and coach is that the stress/rest cycle is a moving target. There are so many factors that can affect either part of the equation. You experience this in your own running. Let’s say you do an easy run each Friday, for example, and one Friday you feel good, so the training stress is minimal and another Friday, you feel terrible, so the training stress is much greater for that same “easy” run. Thus, balancing the stress/rest cycle is really a dance between your planned or expected stress/rest cycle and how you actually feel (the actual stress/rest cycle). (You will like my video Which Runner Showed Up Today.)

While sometimes feeling good or not so good seems to come out of the blue, more often there are several factors that affect each part of the equation. As you train, your goal must be to positively influence and at times adjust each factor, so you get the training stress you want and then recover appropriately.

Common factors affecting the stress part of the equation

  • Intensity of run/workout
  • Duration of run/workout
  • Preparedness for the run/workout
    • Fuel
    • Hydration
    • Mental state/Motivation
    • Musculoskeletal readiness
    • Equipment
  • Non-running factors
    • Heat
    • Humidity
    • Wind
    • Terrain
    • Training partners
    • Life/Work stress
    • Health status

Each of these factors can make the run/workout more or less stressful. And, some of them can be controlled (you can make sure you are properly hydrated) whereas some are not (“can’t control the weather” as they say).

The point is that the stress of training is not just related to what you expect when you look at your training plan. It gets a bit more complicated based on how you feel on the day. That’s why the “stress” you get from an easy run is not always the same. So, it’s an ongoing evaluation to determine the level of stress you want from the day and/or the level for stress you got from the day and how that affects the rest part of the equation.

Speaking of the rest part, there are many factors that affect this part of the equation as well.

  • Nutrition
  • Hydration
  • Sleep
  • Mental stress
  • Environmental stress
  • Life stress

As with the stress part, there are some factors that can be controlled and others that can’t. As a result, your planned “rest” part of the equation may or may not match what you expected when you looked at your training plan. You may have thought that you’d easily recover from that Tempo Run you did on Tuesday but suddenly there is an emergency at work on Wednesday and you end up missing sleep, skipping meals and being very stressed on the day that you expected to just do an easy run and be fully ready for your next key workout.

Again, this shows just how important the stress/rest cycle is and just how ongoing the process is to balance it. Every great coach I’ve been around (and that includes legends like Lydiard and Vigil) seems to have the innate ability to pick up on any slight nuance in the stress/rest cycle and make subtle adjustments, so the athlete continues to advance fitness and never gets overtrained.

And this is the real secret to success. You must feel empowered to adjust your training on the fly. You must become your own coach to a certain extent. If there is one concept that has led to so much success in my training system, it’s my encouragement of runners to listen to their body/mind and make adjustments to balance the stress/rest cycle.

It’s easy to do (or at least it should be) and once you start adjusting to keep the stress/rest cycle in balance, you see your injuries go away, the quality of each training week go up and your motivation/enjoyment skyrocket. Sounds good, doesn’t it?!

Make sure to read my article on how to Optimize Every Run for details on how I help athletes make adjustments but in a nutshell,  you need a few things:

  • You need a training plan that has wiggle room in it. In other words, don’t pick a plan that requires your life schedule to go perfectly for you to complete your training. Life will get in the way so choose a plan that is doable even if life gets a little crazy.
  • You need to feel empowered to make adjustments. Too often, runners want to complete every week to a “T” but that’s not how it works. Training plans are not set in stone and even the ones I created for the Olympians I have coached required a lot of adjustments as we actually trained.
  • You need an easy way to make adjustments. For my system, it’s very easy. You can drag and drop workouts to move them around when you need to and I provide a range for things like volume, pace and number of repetitions. Feeling good? Run the higher volume, faster pace and more repetitions. Feeling bad? Do the opposite. This makes it easy for athletes to adjust based on how they are feeling and they are soon amazed at how these subtle on the fly adjustments keep their training on track.
  • You need to err on the side of caution. Runners aren’t lazy so their tendency is to do too much rather than too little. That’s why you hear coaches talk more about holding athletes back in training more than pushing them harder. We know that if you can avoid injury, keep training and gradually raise the quality of your training, you will achieve your goals.
  • You need to realize that balancing the stress/rest cycle doesn’t mean you never train hard. That’s the first concern runners have when I teach this concept. They think it means you never train hard. Wrong. You still have the stress part, but you realize the stress part changes from run to run and simply must be balanced by the rest part of the equation. As mentioned earlier, you can train as hard as you like as long as you give your body the rest it needs so it can adapt and grow stronger and faster.

You hear the phase “Listen to your body” all the time in running. The concept of obeying the stress/rest cycle is what this phrase is referring to. You must become attentive to your body/mind and once you do, you can make small tweaks to how hard you are training and how hard you are resting. Your stress/rest cycle will stay in balance nad you’ll see your fitness soar.

I hope this article gives you the empowerment and encouragement to optimize your runs.  As always, let me know if I can be of any help.



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