All Happy Recruitments Are Alike

"Learn to laugh at yourselves. You always move better with a smile." – Marjorie Barstow, Teaching Aphorism.

"All happy families are alike; each unhappy family is unhappy in its own way." 
— Leo Tolstoy, Anna Karenina

All happy recruitments are also alike; each unhappy recruitment is unhappy in its own way.

What is recruitment?

Today is my Science Day, so it's back to talking about red non-fatigable muscle fibres — which scientists call Type I fibres — and white fatigable muscle fibres — which scientists call Type II.

Every muscle houses both Types, so, as we shall see, which Type fires determines how efficient — or how tiring — your Pilates practice becomes.

Let me dig a little into energy use to explain why. You may be surprised by what I am about to explain. The key reason these two Types differ is the way they burn energy. Type I is aerobic (red), Type II is anaerobic (white). Being able to use Oxygen was a big breakthrough in the development of life itself - "The Great Oxidation Event" 2.4 billion years ago made oxygen available so the aerobic process could evolve.

Alternatively, anaerobic fibres extract energy from glucose without oxygen — but without oxygen, the process stops early, producing lactate.

More on lactate in a moment.

Why does this matter to you practising Pilates?

It matters because of energy efficiency. You get energy by extracting it from a molecule of glucose, which produces units of energy that physiologists label ATP.

One molecule of glucose processed aerobically will yield between 36 and 38 ATP units. Nice.

The same molecule processed anaerobically yields only 2 ATP units. Whoa!

36 versus 2. Which fibre Type would you like to recruit for everyday use?

Now — about that lactate that the anaerobic process produces. The burn and fatigue that make you want to stop exercising — long blamed on lactate, but now understood to also involve hydrogen ion accumulation — is one undesirable consequence of overfiring your Type II fibres.

How do you improve the recruitment of those delightful red Type I fibres?

It turns out your Postural Movement System (PMS) is deeply wired into the Type I fibres. While the precise mechanisms are still being mapped, the connection is reasonably well-supported through Henneman's Size Principle — a firmly established physiological finding that the nervous system will ordinarily recruit from the smallest, typically Type I, fibres first.

It is generally understood that your Voluntary Movement System (VMS) is biased toward Type II fibres. Which means if you try too hard, and use voluntary effort to replace postural support, you are spending a great deal more energy to do it.

My precious teacher, Marjorie Barstow (1899–1995) — when asked what she did for a living — would sometimes answer:

I study the conservation of energy.

Without knowing the science, Marj saw the results — both in her Self and in her students. You have more energy because you waste less of it. PILANDES promotes exactly this kind of conservation.

Not to disparage the poor Type II fellows too much — they are very useful when you need bursts of speed and power, which you often do. Older people can suffer from a lack of this ability.

But Pilates is not in the same class as HIIT training. Pilates is measured, deliberate, and sustained. Which makes it ideally suited to the aerobic Type I recruitment of non-fatigable fibres. Maybe Mr Pilates wanted this kind of family?

In a happy recruitment family, the Type I fibres do all the housework that supports the family. When those rascal Type II fibres start to think they are in charge of everything, all kinds of unhappiness results.

Don't take my word for it — come to a PILANDES workshop to explore the practical applications of this knowledge.

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