Running an extra mile. Taking an additional spin class. Doubling your HIIT sessions. These are essential to improving your training goals, right? Not necessarily. If the results are overtiredness, lack of quality sleep and ongoing muscle soreness - to name just a few - then you may be doing yourself more harm than good. In fact, you could be suffering from overtraining and post-workout fatigue.

Gabriela Zerger, Wellbeing Manager at Aspria Uhlenhorst, tells a familiar story. Bumping into a member of the Hamburg club she’d once helped to train, Gabriela asked how she was getting on. “Really tired, lacking motivation and appetite. But I want to double my training,” came the reply. Seeing her pale complexion, Gabriela was immediately concerned and urged the member to take two weeks of rest - no spinning, HIIT or cardio. “She didn’t seem convinced at first, so I explained the physical and psychological impacts of overtraining, and used the petrol tank metaphor: we cannot drive for unlimited distances; sooner or later we have to stop to refuel the tank,” Gabriela explains.

Too much exercise is the result of either overreaching or overtraining. Overreaching is when a single training session is more challenging than usual - and a normal part of taking your fitness to the next level. But this requires proper and sufficient rest afterwards. Overtraining is when overreaching becomes part of a regular workout, but we ignore the signs our body is sending us of its need for rest and recovery. It is easy to reverse the effects of both overreaching and overtraining, but the latter may take longer.

Of course, for those looking to progress to increased levels of fitness, each training session cannot be made up of the same exercises, to the same intensity, for the same length of time, so introducing one or two “overreach” steps - a heavier weight but fewer reps, for example - is important to achieving your goals. But so is understanding your body’s limits.

“Appropriate tiredness and muscle soreness after a workout should resolve itself within one to three days,” Gabriela explains. “But as soon as you start to have problems sleeping, perform less well at work, even gain weight and experience irregularities in your menstrual cycle, then that’s overtraining.”

Other symptoms include being unable to stick to a regular workout routine and changes to your normal patterns of behaviour and mental health, including irritability and anxiety. “The body is an incredible machine that tells us what it needs, both physically and mentally,” says Gabriela. “Listen to it.”

As well as high-intensity training without rest periods in between, overtraining can be caused by dehydration and low blood sugar. So drink plenty of water before, during and after your workout, and eat a carb-fuelled meal or snack before training to ensure your glucose levels can sustain your workout. We delve deeper into energy-boosting nutrition in this article.

“In order to avoid overtraining, it is helpful to understand how our body functions during exercise,” Gabriela explains. “When we train, our body burns energy and we feel tired, but if we rest, eat a healthy diet and sleep well, we build that energy back up to allow us to train again. This is a healthy cycle we should follow.”

When the body is pushed too far without appropriate rest, the right food and enough quality sleep, the cycle is broken, leading to overtraining and possible injury. The right amount of recovery time depends on the individual workout schedule. Unsurprisingly, someone who trains at a slower pace and focuses on body weight exercises will need less time to recover compared to those who train at HIIT level with high-volume weights.

But a good rule of thumb for everyone is to train for up to 5 days, stretch or do yoga on day 6, then rest completely on day 7. “Anyone can suffer from overtraining, but those who spend a lot of time in the gym or focus primarily on strength training are more susceptible to it,” says Gabriela. “As are people who do not understand that recovery, stretching and sleep are important factors in our fitness journey.”

According to HSS sports psychologist Deborah N. Roche, quality sleep, nutrition and mental wellness are critical to preventing overtraining. “These must be part of the training regimen just as much as the exercise and rest plan,” she says. “Many of us use exercise to manage stress. It can be a great way to clear your head and enhance your mood. However, you can have too much of a good thing.”

In addition to a minimum of two weeks’ rest - (we recommend consulting an expert or personal trainer for advice tailored to your needs) - there are other ways to help you recover from overtraining. Those of us who exercise regularly often find it difficult to rest; whilst we recover physically, our mental health can suffer as a result of inactivity. Practising mindfulness and meditation is a great way to find balance - and should be incorporated into a regular training schedule, even before overtraining occurs.

Depending on the extent of your post-workout fatigue, you may be able to attend a stretching class - ask one of our experts for advice. A massage or visit to the sauna are also great ways to help your mind and body to relax, aiding sleep and rejuvenation.

After that, your body will be ready to work out again, as Gabriela discovered when the member came back to see her two weeks later. “She burst into my office and said she felt like a completely new person – well rested, having gained strength, with improved sleep and lower stress levels,” says Gabriela. “Her face was glowing, her cheeks were rosy: a happy, rejuvenated woman ready to take on the next step on her fitness journey.”

For more advice from Gabriela on how to avoid overtraining, including how to create an optimal training schedule, read her piece on post-workout recovery. Happy training!