Training and your body 1: On the purpose of training

If you ask any athlete why they train you will probably get answers ranging from “to improve” or “to get better at my sport” to something more specific like “to get faster/stronger/more precise.”

If you are talking to a particularly nerdy human being (such as myself) or a recent Kinesiology graduate you may even get something a little more scientific such as “to cause adaptation” or to “stimulate muscle growth.” This would be more where I am headed – but still not quite it.

An answer you probably won’t hear is this: to cause stress. No, not that nasty psychological stuff, although some days training can be really hard on the head. The purpose of training is to put stress on your body. Stress, in turn, can lead to adaptation. Although training CAN (and should) lead to improved performance, there is a chain of events that links successful training protocols with improved performance on the other end. So lets start at the beginning: Training → Stress.

General Adaptation Syndrome (GAS)

Although our understanding of Dr. Hans Selye’s (1936) theory of general adaptation has expanded a great deal over the years the fundamental principals have held true. The basic premise is that repeated exposure to sub-lethal physical stressors cause organisms to become more tolerant of that stressor. In this case we are talking about the training context, so the stressor is the workout and the organism is you. The body’s response to stress moves through three phases called the General Adaptation Syndrome. Each phase is characterized by a unique set of physiological responses which are summarized below:

Phase 1: Alarm.

The immediate response after being exposed to a stressor (e.g. squats). Homeostasis of the body is disrupted.

Physiology: Rapid loss of muscle tone lasting about 48 hours. Acute-phase hormonal responses and cellular flooding. Inflammation and stiffness at the accompanying joint(s).

You will feel: fatigue, stiffness, drowsiness, and “used up.” You will note small performance decreases such as slowed movement.

Phase 2: Resistance.

The body resists the damaging effect of the stressor by mobilizing resources to counteract its effects and increase tolerance to future exposures. This is where we see adaptation and it occurs when we provide our body sufficient time and resources for recovery. This stage typically begins 1-2 days following exposure to a stressor and lasts until adaptation is complete. The time-frame varies greatly depending on whether the individual is a novice (1-3 days), intermediate athlete (a week or two) or an elite level athlete (1-4 months).

Physiology: Modulation of gene activity, changes in hormone production, increases in structural and metabolic proteins.

You may feel: Depending on the size of the stressor and your tolerance for workload: Delayed Onset Muscle Soreness (DOMS), joint pain, disrupted sleep and physical fatigue lasting several days. You will note performance decreases while this adaptation occurs.

Phase 3: Exhaustion

If we apply too much stress, for too long, or too frequently we will not be able to adapt to that stress and exhaustion will occur. This is often termed “overtraining,” which we will discuss in more detail a few posts from now so I will not expand here.

Physiology: We will get to this in a few weeks.

You may feel: well, exhausted.

So it all starts with training in order to induce stress. This is the first step in the GAS and what starts the chain to improved performance.

Training →  Stress → Recovery → Adaptation → Increased Performance

What do we learn by knowing that the purpose of training is to induce stress?

First, if we do not apply a large enough stressor, we do not cause stress and therefore no improvement in performance as a consequence. If you can already do 3 pull-ups, starting each day off with 3 pull-ups will in no real way make it so you can do 5. Your body has already adapted to the stress of 3 pull-ups and unless you modify the stressor your performance is unlikely to increase. This is why most people who workout on their own achieve no real performance gains – because they do the same routine week after week with the same weight and exercises. They make progress at first while their body adapts, but once adapted, that routine is no longer a stressor and can no longer drive changes in performance. This is also why we want you to keep a training journal: so the next time you come in you don’t pick the same load you squatted last week and squander an opportunity to induce stress!

Second, we know that training induced stress is likely to lead to temporary decreases in performance while your body repairs itself and adapts. Don’t be surprised if you can’t match your PR back squat 2 days after you got it the first time. You just learned how to do muscle ups on Monday – don’t be shocked if you can’t do 1 on Wednesday!

Third, sustained stress can lead to exhaustion – so don’t overdo it. Although this is rare, it can happen and is most frequent when recovery habits are poor and training volume and frequency is too high. In my next post I will talk more about that second link in the chain: Recovery.