[6-min read]

We’ve all heard the phrase “Use it or lose it”. The unfortunate thing is however, when it comes to fitness and performance levels, the phrase is extremely accurate, as can be explained by the Principle of Reversibility. Just as our bodies adapt to increased training loads and intensities experienced during a training program to increase fitness and performance levels. It also adapts to the cessation of activity and inadequate training load with atrophy, leading to decreases in fitness and performance (Powers and Howley, 2007). Making the Principle of Reversibility the enemy of athletes or anyone who is training to increase their fitness levels.

While it can’t be completely avoided, there are certain tactics coaches can apply to minimize its effects and maximize their client’s and athlete’s progress which we’ll now discuss. But first, let’s take a closer look at the Principle of Reversibility and why it’s so important.

What is the Principle of Reversibility?

The Principle of Reversibility is one of the core principles of training. It is defined in the Oxford Dictionary of Sports Science & Medicine as “the gradual loss of beneficial training effects when the intensity, duration, or frequency of training is reduced”. Other authors including Powers and Howley (2007), and Korey (2019) describe it as “the observation that withdrawal of tissue loading results in a loss of beneficial fitness and performance adaptation”.

In simple terms, it states that without consistent stimulus, fitness and performance improvements achieved through a training program will be lost over time. Reinforcing the importance of adopting a long-term view of your training and applying the training principles consistently over a long period of time as highlighted by Shayne Murphy. Rather than using training as a means of obtaining some short-term objective or quick fix, because unfortunately, they don’t exist.

How quickly does it happen?

Multiple factors influence the speed at which the Reversibility Principle takes place to reduce training effects and each client and athlete will be impacted differently.

1 / The Individual

Factors related to the individual like their genetics and age will have an impact on how they respond to de-training.

2 / Their Training History

The individual’s training history also plays a considerable role in their response to de-training. Training effects for a given fitness quality produced over a short term tend to be lost much more quickly than those produced over a longer-term. For example, an athlete who has trained for years will feel the impact of a break less than a person who has just trained for a number of months. Individuals who have undertaken quality training for longer are also more likely to regain previous levels of fitness faster than a lesser trained individual.

3 / The Type of Fitness Quality

The type of fitness quality also has a significant impact on the effects of the Principle of Reversibility. According to research, aerobic fitness will suffer the greatest decline with Mujika, and Padilla (2000) finding that aerobic capacity markers will start to demonstrate significant detraining effects within 2 to 3 weeks of training cessation.

Strength and force production was found by the same authors to decline at a slower rate with significant declines noticed in about 4 weeks of training cessation. However, highly trained athletes’ eccentric force and sport-specific power may suffer significant declines prior to this.

Flexibility was found to decline at a similar rate to strength with up to 30% loss across hip, trunk, shoulder, and spine tests observed after 4 weeks.

Why is the Principle of Reversibility so important?

Depending on your context and the goals of the individual you are training, understanding the Principle of Reversibility and its impact can be critically important for many different reasons.

First and foremost, in order to develop safe and effective training programs coaches need to understand that their clients and athletes can’t pick up exactly where they left off after a period of de-training. Placing them on a program with the same volumes and intensities they were handling before their break will put them at a higher risk of injury which could lead to even more downtime. After a period of low or inactivity, the client or athlete will need an adaptation period in order to adjust to the demand again. Monitoring their responses to the increased training stress and gradually building up their volume and intensity based on these responses is advised.

In a competitive environment understanding the Principle of Reversibility is also critical when you consider that the athlete that can avoid the effects of reversibility most successfully will be at an advantage. Therefore coaches who understand the principle and how to overcome it will give their athletes the best chance of performing and winning.

How do I overcome/minimize the effects?

There are a number of tactics you can use to overcome and minimize the impacts of the Principle of Reversibility.

Training Consistency

As alluded to earlier, there are no quick fixes when it comes to improving fitness and performance qualities. The training principles of specificity, progression, overload, adaptation, and reversibility require regular and consistent application in order to improve fitness and performance. As a coach, it’s important that you apply these principles throughout your training programs and help reinforce them with your clients and athletes so that they realize that a long-term lifestyle approach will be more successful than a short-term approach.

Maintenance Programming

During planned downtime, like when your client is on holiday, travelling for work, or when you have an athlete in the off-season, providing a maintenance program with significantly reduced volume can slow the rate of loss substantially. Maintaining fitness and performance qualities is much easier than developing them so this can be very effective in minimizing losses over a period of a few weeks.

Managing Expectations

Managing your client’s and athlete’s expectations is also hugely important. After a period of downtime, especially if it was injury-enforced, it’s highly likely that they will want to hit the road running at the full intensity that they were training at before the break. In this case, communicating effectively with them is important so that you can hold them back slightly and build up their volume and intensity safely over a number of weeks to avoid putting them at increased risk of injury and more potential downtime.

Summary

Due to the Principle of Reversibility, it is inevitable that there will be some level of loss of fitness and performance qualities after a period of de-training. It’s important to understand why and how this happens so that you can deliver safe and effective programs to your clients and athletes based on their context and goals, giving them the best opportunity to stay injury-free and perform. While keeping certain tactics in mind, like consistently applying training principles, providing maintenance programs during downtime, and managing your client’s and athlete’s expectations when they return, to help you overcome and minimize the impacts of the Principle of Reversibility, and maximize progress. 

References

• Powers SK, Howley ET. The physiology of training: effect on VO2 max, performance, homeostasis, and strength. In: Powers SK, Howley ET, editors. Exercise Physiology: Theory and Application to Fitness and Performance. 6th ed. New York (NY): McGraw-Hill; 2007. p. 261–2.
• Mujika, I. & Padilla, S. (2000) Muscular characteristics of detraining in humans, Medicine & Science in sports and exercise, 0195-9131 (01) pp. 3308-1297.