Training Science Series #3 - Overtraining Syndrome (OTS)

Overtraining syndrome (OTS) is a very complicated and poorly understood form of fatigue that doesn’t respond well to just typical levels of sleep and minor reductions in training. OTS is very common because most athletes are not able to recognise overtraining until it is too late.

Training Science Series #3 - Overtraining Syndrome (OTS)

Overtraining syndrome (OTS) is a very complicated and poorly understood form of fatigue that doesn’t respond well to just typical levels of sleep and minor reductions in training. OTS is very common because most athletes are not able to recognise overtraining until it is too late.

This is an article series designed to help further educate my Performance Coaching clients, but also anyone interested in learning how to train more successfully. If you are interested in getting fitter -- irrespective of whether you are a novice or regular athlete -- then please read through this series and learn more about the endurance training process. I also hope to welcome you onboard as your performance coach one day if you need mentoring to reach the summit of your athletic potential!

Understand the Process to Commit 100% to the Process


Overtraining syndrome (OTS) is a very complicated and poorly understood form of fatigue that doesn’t respond well to just typical levels of sleep and minor reductions in training. OTS is very common because most athletes are not able to recognise overtraining until it is too late. The most common signs of the early stages of overtraining syndrome are a general lack of motivation, and repeated shortcomings in performance accompanied by feelings of flatness or low energy. It will feel like you can’t raise your heart rate even during hard efforts. Scott Johnston explains:

When I suffered from OTS, my blood tests were all within normal ranges, and there was no identifiable problem medically other than high morning cortisol levels. Physically I felt like an 80-year old, I would wake up from 10-12 hours sleep, not feeling like I gained any rest at all. Running faster than a shuffle took all my willpower and couldn’t be sustained for very long. I experimented with different diets thinking something was missing, all to no avail. It took a long time to overcome. Johnston warns, “Overtraining syndrome is responsible for more failed athletic goals and shortened athletic careers than any other factor besides injury. Some athletes struggle with it over several years of stagnation before throwing in the towel."2  Ultimately, completely sedentary rest wasn’t helpful to my health, but very low-intensity exercise and easing back into training helped me get back on track and move forward successfully with a new long-term approach to training in mind.

A common term you will hear in training is overreaching, and this should not be confused with overtraining, because it is a useful advanced aspect of progressive training that can help athletes break through plateaus in training (think back-to-back long runs to prepare for the demands of a 100-mile ultramarathon). Overreaching causes a temporary fatigue state caused from a brief bout of excessive training load beyond an athlete’s capabilities. This fatigue is a normal part of training, but it should not linger for too long following hard training sessions. If overreaching is followed by a suitable recovery period of somewhere between 2-7 days, it results in a supercompensation response to the training, improving overall performance. Too frequent overreaching can be a cause of overtraining, thus there can be a very fine line between maximum performance potential and complete physical breakdown.3

All physical training causes the body stress. The continual application of inappropriate levels of activity, creates high levels of cortisol, a catabolic stress hormone that is designed to increase sugar in the bloodstream often by breaking down muscle for fuel, and curbing bodily functions that would be nonessential in a fight-or-flight situation. The long-term activation of this stress-response system leads to many health problems and a big decline in fitness performance.

A certain level of catabolism is a natural response to training stress that hard workouts create, so a small amount of this stress actually benefits the body to develop endurance adaptations. This is how you become fitter and stronger, but only when given adequate rest to do so. Ultimately, this is the “stair-step” approach to training progress, but the steps do not go upward endlessly. They are more like stairs in a skyscraper, where there is a flat landing between each short section of stairs allowing you to pause at each floor before ascending the next flight of stairs. Those landings equate to recovery periods in this analogy. Without a landing, the staircase would just run into the wall of the building and you can’t progress any higher. Each floor needs to be scheduled downtime for greater rest before the next block of training begins.

Thus, to make progress successfully, the body needs these planned rest periods to reinforce the new training adaptations. In training science, this is called Modulated Training and is one of the key parts of my Performance Coaching process. My athletes typically never go longer than a few weeks when increasing their base training loads before we implement a longer period of recovery to solidify those training adaptations and create the necessary supercompensation effects. When we do periods of overreaching, these would occur more frequently.

When there is not adequate rest, the body suffers chronically high levels of cortisol, identifiable from a blood test that checks for it. As seen famously in CrossFit4, when HIIT training is executed in high-volume in conjunction with already intense strength training, athletes quickly get struck down with rhabdomyolysis. This is a very serious health problem involving dangerous levels of rapid catabolic breakdown of muscle tissue into the bloodstream. Many endurance athletes have also been diagnosed with rhabdomyolysis, especially ultrarunners who just completely overdo it from training and racing too often.5

Despite, so much evidence available showing over using utilization training won’t work long-term, many individuals like to think they are the rare special case, who can handle high intensity training better than everyone else. Yes, there are very rare exceptions, but you are likely not it, and are just the same lump of genetic material as everyone else. Sometimes we have to learn from our mistakes, and I am no exception, but it’s a terrible waste of time to learn the hard way. I learnt everything I write here, the hard way over more than a decade of highs and lows in endurance sports. I certainly would be a far superior athlete if I had known about and listened to the advice in this article when I started out.

There are ways to limit the catabolic effect of endurance training and induce an anabolic growth response that lowers cortisol, but rest must be paramount in doing this. The unethical and unhealthy way is through doping with anabolic agents like steroids, but bear in mind these artificial substances involve cardiac toxicity and other health issues.6 The healthy and ethical way is possible through application of proper post-workout nutrition7, adequate sleep and so on. Furthermore, consuming sufficient levels of protein and calories to fuel the training loads is absolutely crucial. There is a very strong link between lack of calories and overtraining syndrome, which is being borne out in the new science breakthroughs relating to RED-S (Relative Energy Deficiency Syndrome). This syndrome is most common in women athletes who under eat calories in an attempt to lose weight or stay lean - but it can also affect men who don't eat enough to fuel their training loads. It has been found athletes who ingest a mix of protein with carbohydrate following training improves overall muscle rebuilding compared with carbohydrate alone offsetting the need for the body to break down its own muscle tissue.8 The inclusion of a functional strength program for runners also helps to maintain more of an anabolic metabolism, but should be carefully applied not to induce more fatigue. Ultimately, there are training intensities that do not cause an increase in cortisol, and those are beneath what is called the Aerobic Threshold (more on this later).

Thus, a crucial element of elite performance is to find the proper balance between training and recovery. Elite athletes push up against this wall constantly and requires a very refined training program to lower the chances of OTS.  Working with a knowledgeable coach is the smartest way to prevent OTS. The number one reason most people don’t achieve their running related goals – and fill doctors’ and physiotherapist office’s – is due to interruptions in their training from injury or fatigue ultimately created from a poor training approach.

Self-coached athletes with a “make it up as you go” style have the greatest tendency to fall victim to OTS because they don’t have the benefit of an unbiased observer to appropriately plan and police their training. Many athletes tend to think they can handle more volume and intensity than they actually are ready for. Athletes who blindly follow generic training plans without understanding their underlying principles may also be pushed beyond their limit, if the plan is not specific enough or appropriate for to their fitness level. Many downloadable or generic training plans tell you how much distance you should run throughout a series of weeks, but often fail to take into account intensity to be applied and other factors such as temperature stress, changes in terrain elevation/difficulty, outside personal stress, and so on… In most cases, the common theme is an athlete runs too fast and too frequently for their current level of ability. An experienced coach can weigh up all the outside factors, observe various training metrics and keep an athlete healthy. It’s hard to do on your own, but it is possible if you make self-education more of a priority.

Furthermore, all athletes should be flexible and be willing to deviate from a training plan when early OTS signs show up. When in doubt, it is always better to be undertrained than overtrained, because being well rested will allow you to just push harder if you need to, but with OTS, your body will give you nothing, no matter how much willpower you invoke. Part of my coaching process involves monitoring an athlete’s energy levels from each workout using a self-ranked grading system from A to F. If an athlete starts logging too many B’s and C’s, then we can back off the training and get them back to consistently logging A’s. This is one metric I use to ensure OTS is stopped long before it becomes a serious problem.

Another demoralizing form of OTS is the body’s failure to adapt to the training regime. You likely have OTS if the increase in training load results in no improvement, or leads to a further decrease in performance. Overtraining is easily noticeable by track athletes or those with routine training routes, but harder to observe in mountain sports where the training routes are typically changing on a daily basis. The use of benchmark workouts can be a useful way to test whether training is progressing or regressing.

Equally, an overuse injury can be an indicator of overtraining and is probably an indication volume progression is increasing too fast for the athlete’s ability, and the adaptations you are seeking through training are not occurring. Injuries can also happen if volume is appropriate, but the athlete is not regularly on top of releasing tension in musculoskeletal soft-tissue, which can be a normal response to the terrain demands of mountain sports (primarily downhill eccentric loading).

Remember that training is not the only stress you have in your life and very few athletes have this luxury of a stress-free life. Failure to take these factors into account can easily lead to OTS. In times of elevated life stress, be prepared to reduce your training volume. Resuming training must occur carefully and tough decisions should be made regarding race goals when training has been compromised.

No matter what your training plan states, if you feel overly tired (beyond the usual), you should rest. You should never feel like you must do a block a training. Taking two weeks off completely could save a year of training in your future. Pulling back can be like admitting failure, but there is no substitute for rest to heal from OTS. Also, when you return to training you must resist the temptation to return to where you left off. The whole training plan will have to be re-evaluated and redesigned to ensure the problem does not reoccur. The cost of overtraining and under recovering is so much worse than undertraining; it is far better to err on the conservative side. Even someone super experienced like Jornet, noticed he was overtraining, so we can all fall victim of it when we get carried away. He explains:

This is why understanding overtraining syndrome is important, primarily listening to the early warning signs and stepping back to take needed rest. Even if you have a strong aerobic base in place, too much added high-intensity will always set you back. Jornet shows how resting, getting blood tested, taking care of diet and a strong focus on diet/supplementation for red blood cell creation, and returning to very easy training is always the answer to getting back on track.

Ultimately, the one solution to OTS that is unavoidable is a long period of rest. At the minimum, it should be several weeks of complete rest before you even begin to think of gradually reintroduce easy exercise. In some cases, the rest required may be years before any high-intensity exercise or high-volume low-intensity exercise is tolerated by the body. This scenario is definitely worth avoiding at all cost.

Next Article -> Part Four- Advice for Beginner Runners

Related Posts

Training Science Series #2 - The Utilization Training Problem

The best way to build endurance isn’t to repeatedly leave nothing in the tank with each workout. Some people regularly go out for a 30, 45- or 60-minute runs pushed right up against their endurance limit – almost everyday or every other day.

Training Science Series #4 - Advice for Beginner Runners

Beginner athletes are most at risk of overdoing utilization training. When novices start running, they have zero movement economy and technique, so the demands of running can quickly elevate heart-rate into the high intensity heart-rate zones of utilization training.