Rest days for better performance

Meyken Houppermans, PhD. CrossFit Level 3 Trainer.
Founder and Head Coach
Overtraining can be the result of too many high intensity workouts, or too much cardio. Lack of rest can negatively affect performance and overall physical and mental health. Rest days are necessary to improve athletic performance and for better immune system. Specifically for women, rest days are important for a healthy hormonal balance.

Warning signs  

- Lack of energy, severe muscle soreness, or feeling sick

- Weight loss of 2 perfect the day after a workout, or dark yellow pee

- Lack of strength, speed, power or endurance during a workout

- Higher (resting) heart rate

- Feeling sluggish instead of energized after a workout

- Feeling burned out and moody

- Lack of appetite

- Loss of muscle mass, and gain of body fat

- Not being able to lose  body weight although you’re working out more and eating less

- Disturbed sleep

Overtraining syndromes

Overtraining is excessive frequency, duration, volume, or intensity of training sessions causing the body’s inability to recover and adapt. Overtraining has two types: sympathetic and parasympathetic., both treated differently.

Sympathetic overtrained syndrome

The symptoms above are indicators of the sympathetic overtrained syndrome. This syndrome is associated with high amounts of anaerobic activity/ high intensity workouts, lack of variety between high and lower intensity workouts and lack of recovery and/or rest days.

Sympathetic overtrained syndrome can be treated with parasympathetic recovery techniques such as meditation, massages, power naps during the day, as well as with active recovery activities such as brisk walking outdoors, recovery workouts at lower intensity or mobility training. Eating healthy foods and drinking a sifficient amount of water is also beneficial.

Para- sympathetic overtrained syndrome

Symptoms of parasympathetic overtrained syndrome include depression, decreased heart rate, fatigue and decreased performance. Opposite to sympathetic overtraining, athletes often have undisturbed sleep, can maintain a constant weight, and have the capacity to recover well from normal trainings. Parasympathetic overtrained syndrome is associated with high volumes of aerobic activity, or the result of pushing the body too far for an extended period of time: a burnout.

Because the symptoms of the parasympathetic overtraining syndrome are hard to recognize, the situation can take long before it is noticed. A tricky symptom of is a low resting heart rate and a heart rate that doesn’t rise easy during intensive exercise. Many athletes would interprete this as being in good shape when the opposite is the case.

Parasympathetic overtraining syndrome can be treated with sympathetic recovery techniques such as low intensity active recovery workouts. Recovery can take months.

Rest day for better performance

A rest day means no exercise or a light recovery training. This can be mentally challenging for athletes who are addicted to their sport; who have a fear of getting out of shape, losing muscle mass or gaining body fat. They tend to do the opposite of what needs to be done to get better results. It is about training smarter, not always more or harder. If you want to stay in shape and be able to workout regularly in the long run, a rest day is necessary.

During rest the body recovers, restores energy and develops. This does not happen during workouts. During a workout, minor damage occurs to muscle tissue. That damage is required to get the body in better shape. The body needs an incentive to develop, under the condition it is provided with healthy nutrition and a sufficient amount of rest. Only then, performance will improve. Otherwise, the damage is there to stay and the athlete goes backwards instead of forwards.

Healthy nutrition

Healthy nutrition means eating wholesome meals with minimally processed foods regularly throughout the day, on set times in moderate amounts. Every meal should contain proteins, carbs, fats and water.

Protein is required to build muscle and prevent the loss of muscle mass. Options are lean meat, fish, eggs, dairy or a plant- based alternative with vitamin B12 added and a maximum of 1 gram of salt per 100 grams of product. Carbs are required for energy and to restore energy levels in muscle cells. Carbs are in products such as whole grain products, vegetables and fruits. Fat is needed for transport and the use vitamins in food. Sources are nuts, fish oils and olive oil. Water helps to restore fluids and to get rid of waist products like lactic acid. (Why you need a hydration plan)

A sufficient amount of rest

A sufficient amount of rest depends on the athlete. On a weekly base, there should be at least one dasy of not working out or doing a very light recovery training.

Rest day for immune and hormonal systems

Overtraining can affect the immune system in such a way, the body will no longer able to protect itself against pathogens. The athletes becomes weaker and at greater risk of becoming sick or injured.

Overtraining can lead to disturbed hormonal balance. That’s why overtraining is considered a neuro- endocrine disorder. Training has various hormonal effects, but there is still little known about the exact function and role of hormones in the body. Several studies have shown that lack of sleep and too much training can lead to a decrease in (endogenous) anabolic hormones and an increase in catabolic hormones. Anabolic hormones, such as testosterone, are needed to rebuild after exercise. Catabolic hormones such as adrenaline are needed to deliver energy for exercise. In a nutshell: anabolic hormones built you up, catabolic hormones break you down. A lack of rest days keeps to body in an ungoing action mode, being unable to recover and recharge.


Women who exercise too much without recovery can experience a decrease in estrogen levels. In some this is a result of athletic amenorrhoea: the absence of menstruation due to overtraining.  

A decrease of female hormones may lead to severe and sometimes hard to recognize symptoms such as extreme fatigue, muscle weakness, restlessness, nervousness, fluid retention, disrupted fat balance in the body and feelings of depression. There is still little known about the negative effects of a lack of female hormones. Symptoms aren’t always recognized by women or doctors and coaches, sometimes diagnosed as burnout or depression, or only recognized by women in the menopause. (Hormones and vague symptoms)

Rest days for mental health

In addition to the physical effects, rest days also have a mental effect of recharging. Not always being focussed on performing, but also spending time to create head space and paying attention to other things in life, at a different and more leisurely pace. The importance of the body and mind in balance.


Not enough rest equals not being able to respond to training incentives anymore; a decline in performance instead of making progress; and not being able to get in shape anymore. In the long run this may mean the athlete is no longer able to workout at all.

How much rest an athlete needs depends on the type of training, load capacity,  individual physical, mental and emotional condition, and the extend to which the athlete take good care physical, mental and emotional health.

The key to success

It’s important to approach rest days in the same manner as workout days: Planned and part of the routine over a longer period of time. We call his the periodization of the training program.

A professional Personal Trainer or movement specialist can advise you how to set up a well balanced training plan during several months. Sports concepts such as Spinning and CrossFit handle the principles of rest days, recovery training session and periodization to offer an optimal effective program to athletes.

The key to success is a balance between challenging yourself and taking enough rest. It is a mindset, maybe even an ultimate challenge, but you will find that it works and makes you stronger. The moment you let go the idea that you MUST workout, you will find that you’ll perform much better on your next workout and will make more progress and stay motivated. It is a matter of doing less and achieving more.

Create your own health!©