Why it’s important to take a week off from the gym every now and again – the science behind ‘deload weeks’

If you were to think about the key to getting fit, you’d probably imagine you need to spend plenty of time in the gym. But many fitness influencers claim that taking time away from the gym every six to eight weeks – known as a “deload week” – is actually the key to improving fitness gains.

Deload weeks mostly involve toning down the intensity of your workouts. These are typically done during periods of heavy training. The express aim of a deload week is to give the body time to recover from the fatigue and damage that can be caused by periods of intense training.

Intense training or high volumes of training cause us to accumulate damage in our muscle tissues. While this damage is an essential part of the process in improving fitness gains, these improvements can only happen if the body has time to recover.

During exercise, muscles can develop tiny tears and their fibres can become disorganised after intense training. This causes an inflammatory response in muscle tissues which requires time in an “unloaded state” (resting or doing low-intensity exercise) to resolve. This inflammation is actually important for promoting positive changes in our muscles – leading to improvements in fitness.

But if we train without adequate rest we can cause the muscle to be in a semi-permanent state of being slightly damaged. The inflammation doesn’t go away – leading to negative changes – such as our muscles being less able to use oxygen efficiently and poor performance.

By allowing our muscles the opportunity to recover we set them up for success.

Risk of overtraining

Many avid gymgoers may be afraid to take time off from the gym for fear it will cause them to lose their gains. But research actually shows that the genes in our muscles contain a memory imprint – effectively holding genes responsible for muscle growth in a semi-prepared state. This means that our muscles are ready to respond quicker and better to training in the future and promote growth after a period of rest.

Even after long periods of time in a deloaded state (up to seven weeks), your muscular fitness can be restored to prime condition – and even beyond, in some cases. This is true even if you’ve lost some muscular strength during this period. Not only that, but your condition can be restored to its prime twice as fast as it took to get to that level in the first place.

Another reason it’s so important to take time off from intense training is because without rest we may develop muscle soreness – and potentially even overtraining syndrome. Overtraining syndrome is a prolonged period of malaise and deconditioning caused by training too much or too intensely without adequate rest. It can take several weeks to months (and in some cases years) to overcome.

The symptoms of overtraining syndrome are fatigue, poorer performance and mood disturbances. These symptoms occur gradually – meaning overtraining syndrome only becomes apparent when you are in its throes. This is why taking care to rest adequately is a vital part of training.

It’s hard to say how common overtraining syndrome is because the symptoms are so vague. Some studies indicate the rate of overtraining syndrome could affect as few as 10% of elite athletes – but the incidence could also be as as high as 60% in the most competitive athletes.

Rest days or deload weeks?

It’s clear that recovery time is important for both fitness and overall health. Any time you are doing a lot of work in the gym, you should make sure you’re scheduling plenty of time to recover in your workout plan.

Deload weeks differ from rest days in that rest days generally incorporate no exercise (or only extremely light exercise) once or twice a week. Deload weeks tend to involve some training, but at a substantially lower intensity than you’re used to – usually doing around 50% fewer workouts than you normally would, or reducing the intensity of your workout by about 20%.

Both rest days and deload weeks help the body to recover from training, which is important for improving your fitness. It is not a case of either/or. For example, if you are undertaking an intense training regime for a marathon, ironman or crossfit competition, you should be scheduling weekly rest days. On top of that, you should also be implementing deload weeks. If you are a recreational gym goer who works out less strenuously around one to three times per week, then the rest you get from this kind of workout schedule will probably be adequate.

Read more: Rest days are important for fitness – here's why, according to science

Fitness influencers suggest that deload weeks should be included in training schedules every four to eight weeks. This broadly aligns with the expert view of four to six weeks. But, you should schedule in your deload weeks as you need them. If you begin to notice your performance is no longer improving – and maybe even getting worse – it might be time for a deload week.

No training plan should be so strict that you cannot take a step back when you need to. Deload weeks will not only benefit your performance, but also your health.

Daniel Brayson has recieved funding from The British Heart Foundation and Muscular Dystrophy UK. He is on the board of Trustees of the Physiological Society.