Burn - Part One

Constraints, Energy Set Points & Performance

This was a fun read.

• I’m going to share my thoughts about how Chapter 8 (see below) applies to our training.

• I’m also going to share thoughts about how Chapters 5 & 6 apply to our body composition.

The table below explains the basic premise of the book. Daily energy expenditure is constrained and doesn’t increase in a simple linear manner.

If you’ve spent time stressed out, or running an energy deficit, then you will have bumped into constraints.

• If you were paying attention then you will have noticed this slowed, and in some cases eliminated, the benefits you received from exercise.

  • By “benefits” I mean all benefits. It’s possible to detrain, while training, when we are under excessive stress.

• If you’ve trained for many years then you may have noticed the intake required to fuel your training reduced. This improvement (in our ability to produce velocity from food) is a desirable adaptation to long term exercise. Our bodies become more efficient as they adapt to long term load.

The concept of the constrained athlete is one most of us have experienced directly.

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It would be fun to turn Nassim Taleb loose on the data table (below). Each dot is a studied population, not an individual.

There is a lot of variability in the data, at both the study, and individual level.

As we can read in the second to last sentence… It’s not uncommon for an individual’s daily energy expenditure to deviate from the expected value by +/- 300 kcal.

Looking at the study population dots, there appears to be even more variability.

Given the variability in every complex system, especially an organic one called a human body, I am not surprised by the data.

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Constraints

In the book, energy expenditure is constrained. Athletes will encounter other constraints:

• Biomechanical

• Immune System Function

• Sleep

• Emotional

• Financial

• Nutritional & Digestive

• Intensity Tolerance

Many of these are discussed in the book.

In my experience, as a coach and an extreme-volume athlete, the above factors (and others) constrain performance. I call this constraint “total stress load.”

Energy expenditure is a factor in total stress load but it’s not the whole story.

• Not all energy expenditure is created equal.

  • There are forms of energy expenditure that increase our capacity to tolerate stress.

  • There are forms of energy expenditure that reduce our total stress load.

• There are inputs that enhance our capacity to tolerate stress.

• Our constraints interact moving our maximal sustained energy expenditure up, and down.

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Energy Set Points

If we take the premise, that we are constrained at a “set point” that moves upwards and downwards then…

Having a high set point is a good thing for an endurance athlete.

Speaking from experience, this high set point can be a hassle because high set-point athletes are:

• Often Hungry

• Gain Weight Easily

The flip side is high set-point athletes can:

• Do A Lot Of Work

• Gain Strength Quickly

• Gain Muscle Faster Than Most

Knowing your family history, and what sort of athlete you are, can help guide your approach to training and nutrition.

• Are you built like a rower, a marathoner or somewhere in between?

• How do you handle total load?

• Do you break down before, or later than, your peers?

• What’s your illness and injury history?

• Were you chubby as a child? Strong as a teen?

While the chart (above) indexes to “total mass,” one of the best way to lift our set points is to gain lean body mass. Particularly, if we can do this in a functional manner.

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Implications For Serious Athletes

One of the central themes of the book is something I’ve seen and experienced in sport.

As output increases, the athlete will arrive at a point where non-essential tasks are switched off.

If the athlete continues then essential tasks will be impaired.

Every athlete is constrained due a range of factors, as well as how these factors interact with each other.

1. Before an athlete gets sick, or injured, constraints will be slowing adaptations.

2. Proactive recovery, when healthy, can ensure the athlete stays well away from maladaptive stress.

3. Schedule deeper recovery at the first sign of maladaptive stress.¹

What might those signs of maladaptive stress be?

• The book cites sex drive as a bodily function that is down regulated early in the cascade of ill-health.

• My anecdotal experience (as a writer) is creativity is down regulated early in the process of maladaptive stress.

• Sleep, particularly, the ease of falling asleep can be switched off.

  • Knowing this, I front load daily stress so I have a long period to unwind and settle my mind.

• Mood & Motivation. These are subtle (at the start of a downward cascade). When previously stress reducing activities become a source of anxiety… assume you are too tired.

What does this mean, in practice?

Flip all of the above on their heads. We want to start each microcycle with normal levels of:

1. Sex Drive

2. Creativity

3. Sleep Quality

4. Mood & Motivation

When we do a multi-day recovery block we should feel superb. If not, then we are slowing the potential gains from our programs.

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Living With Constraints

Every athlete will bump into constraints as they follow their Endurance Journey.

When we bump into an important constraint:

1. Pause

2. Notice It

3. Reduce Specific Stressors To Stay Under It

How far to back off, for how long? That’s where the art of training (and coaching) comes into play.

• For biomechanical constraints stay under the average load of the six weeks prior to the first sign of problems. Injuries, even seemingly acute ones, often have long lead times.

• A sustainable level of load feels comfortable.

  • If our overall program feels difficult, it is not sustainable.

  • Well before we are forced to abandon an unsustainable program, we will be underperforming.

  • Seemingly small increases, say, less than 10% total training hours can tip an athlete over the edge.

For best results, stay well back from the edge.

Part Two covers:

1. Why we experience difficulty managing our weight when training load is high. Shouldn’t high outputs lead to weight loss?

2. The role of stress and energy availability in long-term body composition and performance.

3. The role of anxiety in body composition and performance.

4. Using stability as a high-performance metric.

5. Manipulating our set points.

6. High return training strategies.

Back to Table of Contents

1. For the full treatment on maladaptive stress… see our series on The Tired Athlete. It includes an elite athlete case study as well as John’s take as a Sports Medicine Doctor.