The principle of reversibility, also known as regression or detraining, is every athlete’s worst enemy. This article looks at what reversibility is, provides some general timeframes, and suggests some ways to avoid it impacting your training.

Let’s get started, shall we…

So What is the Principle of Reversibility?

Uno reverse cards

Your body’s physiology is never static, it is always adjusting, adapting and correcting. Just as your body can get stronger, fitter and more athletic, it can also get weaker, less fit and less athletic.

If you train really hard for six months but then decide to take the next 6 months completely off, you can expect a significant amount of your progress to be lost. and if you decide to train again after this long break you might not be right back at square one, but you certainly won’t be anywhere near the level you were when you were last training.

How Quickly Does Regression and Detraining Occur?

Research shows that the speed of detraining depends on 2 major factors…

1) The fitness quality in question (i.e. strength, flexibility, endurance etc)

Strength and power qualities tend to be more resistant to detraining, with most people being able to go without training for 2-3 weeks before seeing any significant detraining, and experiencing 2-3% decline per week beyond this point.

Endurance training is more sensitive to detraining, with VO2 Max and Time to Exhaustion measures showing between 4 and 25% declines after 3-4 weeks.

Flexibility training is also sensitive to detraining, with reports of up to 30% loss across hip, trunk, shoulder and spine tests after 4 weeks of detraining.

2) How long you’ve trained that quality

People who have trained a quality for longer tend to hold onto that quality better than those who are just starting with it. Similarly, they are also able to regain previously held levels faster through a higher degree of ‘retained’ or ‘residual’ fitness.

It’s not unusual for elite athletes to take month-long training breaks, or very low training volume periods, directly after major competitions, whereas if a beginner attempted this they would go significantly backwards.

How Do You Prevent or Minimise Detraining?

Let’s say that you’re injured or going on a long holiday and you want to prevent your performance from going backwards. The good news is that the amount of training it takes to maintain various fitness qualities is MUCH less than the amount of training it takes to develop them.

For strength and power, one gym-based training session per week with moderate intensity and volume should be enough to prevent detraining.

For endurance, you’ll still need a decent amount of frequency (you can drop it by at most 30%) so don’t expect to go from running 6 times per week to once per week any time soon. What you can do, however, is reduce your training volume (total distance) by anything from 60-90%, providing that you maintain the same speeds and intensity.

So if you were doing 3 gym sessions and 3 endurance sessions per week, you should be able to maintain all of your strength, power and fitness qualities by doing 1 gym session and 2 endurance sessions per week, so long as you keep the intensity up.

With that said, there’s very little research on how long this will work for. In my opinion, you’re probably good following a maintenance programme for around 4-8 weeks, after that, I would imagine things might get a little dicey.

That’s all for today if you found the article useful feel free to share, and as always, if you’re looking for a strength and conditioning coach to help you or your team reach your performance goals, you can book a call to chat with me here.

‘Til Next Time


strength coach

MSc strength & Conditioning
British Weightlifting Tutor & Educator