The signs of undertraining, which typically get most of the attention in fitness, are fairly visible. With the popularity of high-intensity workouts, however, overtraining needs some attention, too, particularly because most of the signs of overtraining are invisible.

A certain level of focus is necessary during higher-intensity workouts, and the feeling of accomplishment that comes with completing a workout has helped increase their popularity. But just like hearing a popular song too often turns the enjoyment into irritation, training your body too hard, too often ruins the enjoyment of the experience and, more significantly, presents several potential risks to your health, mind and body.

Here are some common signs you may be suffering from overtraining. Typically, you’d have more than one of these at the same time to raise significant concern for overtraining. Most of these signs are driven by hormonal disruptions and deep disruptions to the body’s balancing systems from overly aggressive training. Hormones drive everything in your body—you can’t win in a battle with your hormones.

1. Working Hard, But Getting Soft

If you’re working out hard and noticing that instead of getting leaner with more muscle and less body fat, the opposite is happening, overtraining may be driving your hormones to make changes that are the contrary of the ones you desire. In an overtrained state, testosterone levels drop and cortisol levels rise, causing the breakdown of muscle tissue, and increased insulin resistance and fat deposition. 

2. Restlessness, Mental Fog, Disrupted Sleep

This sign is more often seen with excessive aerobic exercise. Your sympathetic nervous system can remain excited at all times, which will leave you feeling restless and unable to focus. Your sleep will likely be disturbed and broken, as well. Even though you’re tired, your body is wired because it’s essentially having a stress response, so the fight-or-flight machinery in your body is operating when it shouldn’t be. 

3. Big-time Lethargy and Deep Fatigue

When this happens, you feel like your “get-up-and-go” just “got-up-and-went.” Your limbs may feel like they are heavy and made of cement. This is more common with overtraining on resistance training, where your parasympathetic nervous system becomes overly stimulated, leading to a decrease in testosterone, an increase in cortisol, a powerful fatigue (both mental and physical) and a tendency to hang onto body fat. 

4. Lost the Will to Train

This is the one that has affected me during the rare times when I have overtrained. When the idea of exercise or anything mildly physical makes you mentally tired before you lift anything, you could take that as a sign of overtraining. When you finish a workout under normal conditions, you should feel acutely tired physically, but energized in both spirit and mind—feeling as if anything is possible and having a general positive vibe occupying your mind. When overtrained, this is not the case. The idea of working out, the act of working out, or doing anything mildly physically challenging is too much to bear. Anyone can have a single day like this, but it may be overtraining if this pattern continues for a week or more. 

5. Elevated Resting Heart Rate

One of the few signs of overtraining that is objectively measurable is an above-normal resting heart rate in the morning upon waking. This is the result of an increased metabolic rate as your body tries to meet the excessive demands of your training. No amount of oxygen or nutrients is enough to outrun the debt created from the overtraining. 

6. Ignore at Your Peril

One additional important observation: Overtraining can lead to chronic inflammation in the body. This will make your joints hurt as everything gets irritated and make life and moving in general an unpleasant experience. However, it can also harm your brain, leading to an elevated risk of neurodegenerative diseases like Alzheimer’s and Parkinson’s. Your brain can’t feel pain, so when you sprain your brain you’ll be unaware of the damage that is occurring. 

7. Overreaction to Undertraining

Undertraining is a huge problem, as evidenced by the increasing incidence of obesity, but for those who do exercise regularly, more isn’t always better. Enough is better. Things have gotten so out of hand that some people celebrate popped and bleeding calluses or vomiting from an intense workout. These occurrences are never good when it comes to exercise and a sure sign that someone doesn’t know what they are doing. Extremism is never a good idea. Hit it hard, but also hit it medium and hit it soft. Mix up the intensity of your workouts and absolutely ensure proper sleep and mental downtime. Like many bad things in life, prevention is better—and easier—than treatment.