Back to Basics Part 0: Exercise Training 101

This is part 0 of our back to basics series: Exercise training 101
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Welcome to our Back to Basics series, where we examine and explain the basic principles that underpin successfully improving performance in almost all types of physical activity.

In part 1, we look at the 6 principles behind muscle building.

In part 2, we examine the most up-to-date research on how to build strength.

Part 3 explores how to increase endurance.

And, in part 4 we finish off by showing you how to develop greater flexibility.

This article, which we’re calling part 0, is the precursor to the information above. In it, we examine and explain the principles and factors that underpin all forms of exercise training, from building the strength and power needed to compete in weightlifting competitions, to the cardiorespiratory fitness needed to successfully run a marathon.

Exercise Training 101

The aim of exercise training is to improve performance in specific physical tasks by systematically causing structural and functional changes in the body.

In the case of weightlifting, this means increasing the contractile strength of muscle fibres, improving neuromuscular efficiency and coordination, and increasing the structural integrity of bones, tendons and ligaments (amongst other things).

If you’re training to successfully run a marathon, ultimately you’re trying to improve the ability of your body to take in, deliver, and use oxygen, as well as efficiently remove waste products (again, amongst other things).

No matter the specific physical task, there are a number of foundational principles that apply to all exercise training, which we’ll discuss below. As in all parts of the Back to Basics series we’ll use the best and most current scientific literature to support our explanations.

Training Overload

Overload means putting your body under more stress than normal

Overload simply refers to placing the body under stress during exercise training [4]. That is, forcing the body to work harder than it normally does. Doing this causes changes in the body that allow it to operate more efficiently.

This is a straightforward concept: Make the body do things that are more difficult than normal and over time it will change to become better at doing those things. Force your body to lift heavy things, and over time it will make changes in the muscles so that you’re better able to lift heavy things (i.e., you get stronger). Force your body to run long distances, and over time it will make changes in the cardiorespiratory system that allow you to run those long distances more easily (i.e., you get fitter).

In the context of exercise training, achieving training overload requires manipulation of training variables such as how long you train for (duration), how hard you train (intensity), how often you train (frequency), and rest periods [9].

Achieving continuous improvements in performance, however, requires not just overload, but progressive overload. Progressive overload means gradually increasing the demands placed on the body. For example, systematically increasing the amount of weight you lift, or the distance you run. Again, this is best accomplished by manipulating the training variables mentioned above.

Using the principle of training overload in a systematic and logical manner will cause your body to adapt in highly unique and specific ways.

Overload: So, What’s the Point?

In order to make improvements in your physical abilities, you need to place greater than normal demands on your body. And, if you want to continuously improve, you have to gradually increase those greater than normal demands.

Specificity of Training

Exercise training principle 2 is specificity of training
When you apply the training overload concept, and place physical demands on your body, it will adapt very specifically to those demands [9]. This is specificity of training.

While there’s likely to be a small amount of carry-over from one type of training to another, the changes that your body makes in response to exercise training will be highly specific to the muscles involved, muscle actions required, range of motion of the movements, and the energy systems utilized [5].

Put another way, specificity can be remembered as the SAID principle: Specific Adaptations to Imposed Demands.

The principle of specificity explains why people who are trained swimmers, for example, often fatigue quickly when running or cycling – and vice versa. It’s also why champion sprinters tend not to be great long-distance runners – and vice versa. This is because swimming, cycling, sprinting, long-distance running, powerlifting, olympic weightlifting, mixed martial arts, and pretty much every other sport and physical pursuit places very specific demands on the body, and the body adapts specifically to those demands with little or no carry-over.

This principle has been repeatedly demonstrated in laboratory experiments. For example, a now-famous study examined the effects of swimming training on cardiorespiratory fitness (measured by V02 max). Fifteen participants completed a swim training program of 1 hour per day, 3 days per week for 10 weeks. Their cardiorespiratory fitness was then assessed while 1) running on a treadmill and 2) while swimming. The results showed that participants had improved their cardiorespiratory fitness, but this improvement was restricted almost entirely to swimming [8]. That is, they showed essentially no improvements in fitness when running on the treadmill.

Another elegant and quirky piece of research involved participants who spent a month training to cycle with just one leg [10]. At the end of the training, the researchers examined various physiological and biological adaptations when cycling with the trained leg vs the untrained leg. They found that the participants had improved V02 max when cycling with the trained leg but not when cycling with the untrained (i.e., their V02 max was the same as before the training), and that the trained leg had undergone significant metabolic adaptations that the untrained leg had not.

Specificity: So, What’s the Point?

If you’re training to improve your performance in a specific sport or physical activity (e.g., soccer or powerlifting) then your training will be most effective if it closely resembles that sport or physical activity in terms of muscles used, their specific actions, and the energy systems utilized.

Specificity of training means that squatting will make you good sat squatting, not necessarily anything else.

For example, if you’re trying to improve your athletic performance during games of soccer, then going for long slow jogs is not going to help. Doing sprints of varying distances and varying intensities, on the other hand, will help. Similarly, in trying to increase your 1RM back squat, doing sets in a leg press or leg extension machine is not an effective way to train. Progressively overloading your back squat is obviously going to be much better.

Individual Differences in Responses to Training

Individual differences means not everyone responds to training the same way
This principle is very simple: Individuals respond differently to particular training stimuli.

Let’s say you take a group of 10 people who are at the exact same level of fitness (or exercise performance) and put them through an identical training program for 10 weeks. At the end of that 10 week program they will, without doubt, be at differing levels of fitness (or exercise performance). Why? Primarily because multiple genetic factors interact to determine each individual’s response to training.

10 different people will respond to training in 10 different ways

This principle is also in play when looking at the effects of training programs on untrained vs trained individuals. Untrained individuals always experience greater relative performance improvements than trained individuals [3]. For example, it’s not uncommon for individuals starting a strength training program to see gains in the 50% – 100% range (e.g., going from 50 lb. squats to 100 lb. squats) within the first few months. Seasoned lifters by comparison usually need to work their butts off just to see gains in the 1% – 10% range.

Individual Differences: So, What’s the Point?

Just because a specific training program worked well for one person, doesn’t mean it will work equally well for you. Exercise training is most effective when it is tailored to your individual needs and abilities. For the most part, trial and error is the only way to discover what specific training programs your body best responds to.


If you detrain, you'll lose the benefits of your exercise training

Detraining is another straightforward principle: If you stop training or participating in regular physical activity, all of the physiological and performance adaptations you’ve gained will eventually be lost. In simple terms, use it or lose it!

The timeframe for this loss differs for different energy systems and body structures. For example, research has found that the benefits of endurance training (e.g., VO2max, stroke volume, and cardiac output) start to decrease rapidly – within 2 weeks – once exercise training stops [1]. Similarly, beneficial changes in muscles, such as growth and improved neuromuscular functioning, will usually disappear completely within 2 months [7].

It’s not all bad news, however: Brief periods of detraining can be used to actually boost your performance improvements. This is due to the fact that the body doesn’t adapt during training; it adapts during phases of recovery [2]. Therefore, periods of heavy training should be followed by short periods (i.e., no longer than 3 weeks) of no training or decreased training to allow your body to fully adapt and prepare for subsequent physical demands.

Detraining: So, What’s the Point?

If you want to reap its benefits and continue improving your performance as much as possible, then exercise training cannot be viewed as a ‘project’ – there should be no start and end date. Rather, it must be a permanent, lifelong endeavour.

Even in highly trained and seasoned athletes who’ve spent years exercising, all of the physical benefits they’ve gained remain temporary and reversible [9]. It may take longer than people first thought, but if you stop exercising you will eventually lose your hard fought gains – you can be certain of that.

Finally, use brief periods of rest from training to your advantage. Just don’t allow them to go on for too long.

Summary (tl;dr)

If you couldn’t be bothered reading the whole of the article, we’ve summarised the key points in the helpful table below:

Exercise Training 101
Training Overload Your body adapts and improves its performance when you place greater-than-normal demands on it. This is Training Overload. Progressive overload occurs when you gradually increase the demands you place on your body over time, causing it to continuously adapt.
Specificity of Training Exercise training is most effective when it closely resembles the sport or physical activity you’re trying to get better at.
Individual Differences in Response to Training Individuals respond differently to the same training. Don’t just copy the training that others do. Tailor and adapt your training to your needs and abilities.
Detraining Use it or lose it! Brief periods of rest are necessary to consolidate training benefits, however all the gains you make are temporary and reversible and will eventually disappear if you stop training.


Well, there you have it: The core principles that underpin all forms of exercise training.

An understanding of these core principles will give you the foundation for designing a training program that produces the performance improvements you’re after as quickly and effectively as possible. All of the subsequent articles in our ‘Back to Basics’ series will utilize and build on these principles.

Speaking of our Back to Basics series, here are the other articles:

If you found this article helpful, then why not share it with your friends and family on social media?

Until next time, remember: When it comes to our health and fitness, we can either make the effort or make excuses, but we cant make both.

All the best with your home workouts,
THFF (The Home Fit Freak)


[1] Coyle, E. F. (1984 ). Time course of loss of adaptations after stopping prolonged intense endurance training. Journal of Applied Physiology, 57 (6), 1857-1864.

[2] Fisher, J., Steele, J., & Smith, D. (2013). Evidence-based resistance training recommendations for muscular hypertrophy. Medicina Sportiva, 17(4), 217-235.

[3] Fisher, J., Steele, J., Bruce-Low, S. & Smith, D. (2011). Evidence-based resistance training recommendations. Medicina Sportiva, 15 (3), 147-162.

[4] Hass, C. J., Feigenbaum, M. S., & Franklin, B. A. (2001). Prescription of resistance training for healthy populations. Sports Medicine, 31 (14), 953-964.

[5] Hawley, J. A. (2008). Specificity of training adaptation: Time for a rethink?. The Journal of Physiology, 586 (1), 1-2.

[6] Kavanaugh, A. (2000). The role of progressive overload in sports conditioning. NSCA’s Performance Training Journal, 6 (1), 15-17.

[7] Keitaro, K., Toshihiro, I., Hideaki, Y., Naoya, T., & Hiroaki, K. (2010). Time course of changes in muscle and tendon properties during strength training and detraining. Journal of Strength and Conditioning Research, 24 (2), 322-331.

[8] Magel, J. R., et al. (1975). Specificity of swim training on maximum oxygen uptake. Journal of Applied Physiology, 38 (1), 151-155.

[9] McArdle, W. D., Katch, F. I., & Katch, V. L. (2010). Exercise physiology : Nutrition, energy, and human performance. Lippincott Williams & Wilkins: Baltimore, MD.

[10] Saltin, B., et al. (1976). The nature of the training response: peripheral and central adaptations to one-legged exercise. Acta Physiologica Scandinavia, 96 (3), 289-305.


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