You know how it goes: no pain, no gain.

This principle has become one of the main truths of the modern era, and we, men, have engraved it into the very core of our masculine brains. It runs in our blood; it beats in our hearts. It is the battle cry of millions all around the world, fighting day and night for the lives and bodies of their dreams.

But let’s face the facts: we often tend to overdo things. And sometimes this attitude strikes back with a crushing blow. Overtraining is a scenario when pain leads to no gain at all. Moreover, it becomes the cause of dreadful health issues, one of the most fearful of which is a drop in testosterone levels.

Testosterone is the primary male sex hormone, the essence of masculinity itself. It is produced mainly by the testes and by the adrenal glands in a lesser amount. Testosterone is crucial for normal sperm development, essential for a healthy sex drive, and it also has powerful anabolic properties (promotes muscle growth). In other words, it’s one of the most important hormones for a man’s health. Period.

And while it is a well-known fact that physical exercises tend to increase testosterone levels, overtraining does just the opposite: it can cut your T-levels in half.

Sounds terrible, right? That’s why it is so important to know your enemy and be aware of its heralds: the main signs of overtraining.

Signs of Overtraining

Overtraining syndrome (OTS) is defined as a pathological condition characterized by an impaired response to excessive training deprived of sufficient resting periods. It affects all the systems of our body, sparing no function or organ. It’s signs and symptoms can be divided into four main groups:


  • Mood changes, irritability, lack of concentration
  • Low motivation
  • Significantly decreased libido (sex drive)
  • Depression
  • Lack of appetite
  • Fatigue


  • Drop in performance, strength, dexterity
  • Slow regeneration of wounds, prolonged pain periods after training sessions
  • Impaired concentration
  • Sleep disorders, insomnia
  • Elevated heart rate and blood pressure


  • Increased susceptibility to bacterial and viral infections (e.g. common cold)
  • Exacerbation of chronic diseases


  • Significant drop in testosterone levels
  • Raise in cortisol (one of the main stress hormones) levels
  • Decrease of the testosterone / cortisol ratio

The main problem with the signs of OTS is that most of them won’t manifest in a clearly fashion. You might be far into the overtraining zone and be totally unaware of it, up until it takes its cruel toll on your health.

This is why rest has always been one of the most important parts of a healthy training routine. Without adequate periods for regeneration, your body won’t ever become stronger, fitter, and healthier. In fact, no rest, no gain. Never forget that this statement is as true as the classic version. You should put more attention on rest and sleeping the appropriate hours for hormonal development. For more information in regards to testosterone and sleep check out this post (How sleep affects testosterone production (Sleep boosts testosterone production).

How Overtraining Can Reduce Testosterone Levels

Now it’s time for some terrible numbers, so let’s get specific. Over the last decades, a lot of serious scientific researches were carried out to confirm the association between overtraining and decrease in testosterone levels. We’ll take a look at the most dramatic of them.

More than 20 years ago, a small study analyzed the testosterone and cortisol levels of five endurance-trained healthy males, with absolutely normal hormonal and spermatogenic background. Overtraining immediately resulted in a drop in their basal testosterone level by whooping 39%, and a correlated boost in cortisol by 48%. Moreover, it turned out that their sperm count decreased by 43% instantly after overtraining.

Another study, held in 2004, researched whether there was a correlation between the feeling of tiredness, overtraining, and blood hormone levels. The results indicated that around a quarter of rugby players who admitted to be excessively tired had a lower testosterone level by up to 30% of the normal range, while one of the athletes experienced a whole 50% drop.

Similarly, a research investigating the testosterone level of professional rowers showed that this parameter was drastically lower during periods of intense training, than it was during periods of rest.

Dozens of other papers state the same truth over and over again: overtraining can directly and heavily impair your testosterone levels. But why is that?

It is believed that one of the main factors behind the development of overtraining syndrome is an acquired instability of the nervous system, specifically the part of it that’s almost primarily responsible of dealing with stress: the sympatho-adrenergic system.

When the stress is more than the body can handle, this delicate framework becomes no longer able to control the processes running in our organism. As a result, hormonal misbalance develops, and everything else follows just behind.

And the most painful part is that this ALL could have been avoided if you’d had enough rest. Not only because it’s crucial for your general health, but also because testosterone is essential for achieving the best results possible. It improves your performance, boosts up your motivation, speeds up regeneration, and enhances muscle growth. Isn’t that what you strive for? Isn’t that what matters?

You bet it is, mate. So breathe in, breathe out, cleanse your mind. It’s time to get that testosterone back to its proper place by having a good and dedicated rest session.

Remember that it’s always easier and healthier to prevent a disease than to treat it, so get yourself plenty of sleep between your training sessions. Dedicate as much of your spirit to it as you do to the gym.

No pain, no gain. No rest, no testosterone.

Both are essential if you want to achieve the best results.


 Overtraining syndrome (OTS) is a pathological state resulting from excessive training without adequate and regular rest. One of its most dreadful signs is a significant (30-50%) drop in testosterone levels, which leads to impaired sex drive, a decrease in sperm count, and a hard time building muscle.

Its consequences are terrible, but the condition itself can be avoided by literally doing nothing. In other words, get plenty of sleep each night, and give your body a day or two between your training sessions. Such an approach will help you to keep your testosterone levels in the normal range, which is just what you need for a fantastic performance and stable muscle build-up.