Capacity Testing and Training

This article introduces some of the raw capacity parameters we use and provides an overview of how we measure them.  Raw capacity is simply the ability to produce power, independent of modality.  It is the foundation of work capacity across broad time and modal domains.  Inadequate raw capacity imposes a low ceiling for fitness.  

The simplest way to measure raw capacity is on the assbike.  Compared with running, swimming or even rowing, the assbike does not meaningfully punish inefficiency, so test results indicate capacity, rather than any technical or skill considerations.  While the assbike is well-suited to testing, effective training incorporates as many conditioning modalities as possible.  

We use five fundamental tests to ensure our athletes are correctly developing capacity.


1) The glycolytic tests (basic and advanced)

2) The threshold test

3) The all-fibers oxidative capacity test

4) The max aerobic power test

5) The self-regulation test (the graduation exercise)

The remainder of this article describes the tests in detail.



Test 1a -  The basic glycolytic test:  Bike 45 seconds for max calories

Key scores:  Calories

What this test measures:  Anaerobic power and ability to manage / tolerate accumulation of the waste products of glycolysis for short duration, ultra-high intensity work.

How to develop this capacity: High intensity intervals, lasting no more than 1:00.  We use a 1:5 work-to-rest ratio, and limit total work to several minutes or less.


Test 1b - The advanced glycolytic test:  5 rounds.  Bike 45 seconds, rest 4:00 between rounds.

Key scores: (1) Average calories per interval (2) Range of scores (high interval – low).  

What this test measures:  (1) Anaerobic power and (2) resistance to fatigue.  A low range indicates an athlete who can effectively clear glycolytic waste products and recover more quickly from very high intensity efforts, whereas a high range indicates the opposite.

How to develop these capacities:  Anaerobic power is developed through intervals, as described in Test 1a.  Ability to process glycolytic waste products is improved via the development of aerobic capacity, particularly systemic oxygen delivery mechanisms and increased capillary density in muscle fibers.


Test 2 -  The threshold test:  Bike 10 minutes for max calories. 

Key scores:  Calories

What this test measures:  Power at lactate threshold; your maximum sustainable intensity.   The 10-minute duration is comparable to the duration and energy needs of a typical MetCon.  

How to develop this capacity:   Threshold power is developed with a balanced conditioning program comprising endurance training, interval work above your threshold pace, and a small amount of threshold work.


Test 3 - The all-fibers oxidative capacity test:  Bike 30 minutes for max calories. 

Key score: Total calories

What this test measures:  This test measures aerobic capacity, but more importantly, provides information about the oxidative capacity of faster-twitch muscle fibers and larger motor units. It is conventional wisdom, but largely inaccurate, that “fast twitch fibers are glycolytic”.  While some produce more glycolytic enzymes than others, all muscle cells have mitochondria and therefore can develop increased oxidative capacity.  The “conventional wisdom” is reinforced by incomplete programming.  An athlete who has developed substantial oxidative capacity in faster-twitch fibers will perform superbly on this test.

How to develop this capacity:  Many coaches misinterpret a poor score to mean that the athlete requires additional endurance training.  The misguided coach condemns the athlete to more steady state mono-structural work, which is unlikely to resolve this issue except in beginners.  Developing oxidative capacity in faster twitch muscle fibers requires activity intense enough to activate these fibers for durations longer than those possible via glycolytic power. 


Test 4 - Max aerobic power test: Bike 20 rounds for max calories.  Work :30 / Rest :30.

Key scores:  (1) Average calories per interval (2) Range of interval scores

What this test measures:  Calories per interval provides information about an athlete’s maximal aerobic power. The range measures the athlete’s ability to work at a sustainable pace.  A high range usually indicates either (a) the athlete probably started too fast and relied on glycolytic power; in this case, scores will drop off precipitously after a few rounds or (b) the athlete cannot to maintain intensity throughout; in this case, the athlete’s scores drop off in the second half of the test.

How to develop this capacity:   Aerobic power is developed through interval training and endurance work.  Aerobic intervals should feature a work-to-rest ratio of 1:1 or higher allowing athletes to work at intensity levels above threshold pace without excessive reliance on glycolytic power.  Varying the duration of intervals trains athletes to familiarize themselves with pacing and managing intensity levels. 


Test 5 - The self-regulation test / graduation exercise: 10 rounds:  Bike 25/18 calories and rest 1:00.   Time cap is 25 minutes. 

Upon completion of each round of 25/18 calories, rest for exactly 1:00.    This is a "hard rest": either get off the of the bike or place your feet on the pegs and let go of the handles.  No coasting or slow-pedaling.  You must rest the entire 1:00.  You may take as long as you’d like to complete the 25 calories.  

Key score:  Completion time.

What this test measures:  This test measures an athlete’s power output and conditioning status.   It also provides insight into an athlete’s ability to pace and self-regulate, to identify the onset of exhaustion, and to carefully apply glycolytic power.   In other words, it measures power as well as an athlete's ability to manage it.  

How to develop this capacity:  We develop raw capacity with a combination of interval, endurance and threshold training.  We consider pacing to be an expression of body-awareness, which is only developed through experience and exposure to varying challenges.   The ability to distill all of that into numerical scores is why we love this test; it’s a “graduation exercise” of sorts.  We've seen it done in 16:38, which includes 9 minutes of rest - that's 250 calories in under 8 minutes of work.   Give it a shot.  

We use these tests to gain insight into an athlete's raw capacity, and help design training to attack limitations.  Athletes typically begin their capacity journey with our Engine Builder program before progressing to more advanced conditioning work.  Engine Builder develops raw capacity across all time domains, energy systems and muscle fiber types.  You can use it as a standalone program or in addition to your current functional fitness program.  

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