This article was provided by Training and Conditioning
By Dr. Terry FaveroTerry Favero, PhD, is Professor of Biology and Conditioning Coordinator for the women’s soccer team at the University of Portland. He has also worked with the U.S. Olympic Development Program.
Visit any weightroom or locker room around the country, and you’re likely to find a slogan on the wall entreating athletes to give all they have and then some: “Pain is weakness leaving the body.” “To give anything less than your best is to sacrifice the gift.” “Whatever it takes.” The words vary, but the message is the same: Work hard. Every day.
Training hard is a prerequisite for success, but it also presents a fine line. Excessive hard training may lead to overtraining, making workouts counterproductive and sometimes even dangerous. Overtraining carries a high price–often a serious injury and the loss of all or part of a competitive season.
Athletes are fiercely competitive by nature, and the best ones want to do whatever they can to gain an edge. But they need your help to recognize the boundary between pushing themselves to the next level and pushing themselves too far. The good news is that access to advanced monitoring techniques, solid research, and time-tested workout strategies provides athletes and coaches today with more information about optimal training levels than ever before.
OVERTRAINING DEFINED
Put simply, overtraining is the result of an imbalance in the training-to-recovery ratio–too much training and competing and too little recovery and regeneration. The difficulty is deciding just what constitutes “too much” and “too little.”
Athletes enhance performance by overloading the body and then allowing it to recover. This stimulus-recovery process is called adaptation, and it’s a characteristic shared by all living organisms. In developing athletes, small to moderate training loads can lead to large improvements in performance if they’re implemented properly.
But while a little is good, more is not necessarily better. The adaptation process has built-in limits that govern both how quickly an athlete can adapt and their maximum capacity to endure intense training. These limitations function as safety mechanisms to protect the body from irreversible damage.
Muscle fatigue, for example, is a protective mechanism that prevents permanent damage to muscle tissue. While localized muscle fatigue protects individual muscles and muscle groups, overtraining syndrome is the body’s way of protecting itself as a whole from multi-organ damage or long-lasting injury.
Overtraining syndrome is a complex and not completely understood set of neuroendocrine changes that dampen both the desire to exercise and the ability to produce maximal force, thus resulting in decreased performance. Train too long and too hard, and the body’s defenses kick in to draw the line.
The American College of Sports Medicine defines overtraining syndrome as part of a continuum that begins with overload training, a process of intense physical work with appropriate recovery leading to normal adaptation. This is healthy and can result in greater work capacity, muscle growth, and other benefits that both athletes and coaches strive for.
The next stage on the continuum is overreaching, which occurs when the intensity of training begins to overstress the body in minor ways, but typically causing nothing more than soreness and some degree of decreased performance. Overreaching is an accepted part of many preseason training camps, such as two-a-day workouts for football programs.
Overtraining syndrome is at the severe end of the continuum, resulting from excessive high-intensity training or rapid increases in training intensity or volume that result in chronic underperformance in practice and competition. The signs of overtraining syndrome are difficult to detect because there’s no definitive boundary between overreaching and overtraining–we expect fatigue and soreness with overreaching, and accept those responses as part of certain phases of the development process.
The difference is a matter of degrees. Overreaching leads to temporary, peripheral markers such as muscle soreness, joint stiffness, and short-term performance and motivational declines. One important distinction is that these effects can be reversed fairly quickly if an athlete follows a sound recovery program and reduces training.
Overtraining, on the other hand, results in a more general, prolonged fatigue that an athlete may describe as feelings of staleness or burnout. The acute physical symptoms are more pronounced as well, and may include a change in resting heart rate (increase or decrease), higher than normal heart rate during moderate workouts, decreased maximum heart rate, and decreased maximal lactate levels. Other common symptoms are disturbed sleep patterns, mood changes, reduced appetite, and difficulty concentrating on mental tasks.
Another reason overtraining syndrome is difficult to identify is that it’s essentially a moving target. As a normal training cycle progresses, athletes expect to be able to work harder and for longer. Even if it were possible to draw a line between the less serious overreaching and the more serious overtraining syndrome, the line would shift as training capacity improves.
Naturally, most coaches and athletes notice performance-related symptoms first, and may overlook the psychological clues–reduced concentration, anxiety, apathy toward training, irritability–that often precede performance deficits. But if the non-physical signs of overtraining syndrome are caught and intervention begins early, athletes can avoid the long-term effects and put themselves back on track for healthy training and adaptation.
CATCHING IT
Athletes in both team and individual sports are likely to experience an overreached state as part of their training, especially in the early stages of the season or training year. Research suggests that athletes in team sports are more likely to stop at overreaching, while individual endurance athletes are most susceptible to progressing past that level to overtraining.
But anyone, in any setting, who works too hard without proper guidance and attention to recovery can fall victim to overtraining syndrome. Following the 1996 Olympic Games in Atlanta, one study indicated that 28 percent of the athletes considered themselves to be overtrained. More recent research showed that almost 50 percent of youth athletes seeking medical care were diagnosed with an overuse injury rather than an acute one, indicating that many of them suffered from overtraining to some extent.
Very few reliable tools are available to detect overtraining. While x-rays and blood tests can look for specific markers of other injuries or illnesses, overtraining typically does not produce definitive diagnostic values. For example, studies involving overtrained athletes show that they may measure higher than normal, lower than normal, or in the normal range for key performance-related hormone levels such as testosterone and cortisol. And physical signs are often not visible until an actual injury has occurred.
So how do you identify athletes who may be risking their health and performance through overtraining? Performance assessments such as maximum strength, endurance, and work capacity tests can be helpful in catching performance declines, particularly in sports like track and field that emphasize concrete numerical performance. With this method, it’s essential to first develop a baseline for each athlete and perform the tests on a regular basis to track progress. But this method is imperfect–many factors can lead to temporary performance declines, and the testing itself is an added stressor that may contribute to overtraining.
Localized soreness and fatigue are also important signs, particularly if they linger longer than normal. Some degree of soreness and fatigue are a natural part of adaptation, but if those symptoms do not normalize within 48 to 72 hours after an intense workout, practice, or competition, the body’s recovery mechanisms are clearly being overtaxed.
Some of the most promising methods to catch overtraining at an early stage focus on psychological disturbances. Tests such as the Profile of Mood States (POMS), REST-Q Sport (Recovery-Stress Questionnaire), and the Daily Analysis of Life Demand in Athletes (DALDA) are popular among sports psychologists for assessing the prevailing moods, stress levels, and psychological profiles of athletes.
For example, the POMS provides a quick, simple way to measure transient active mood states. It asks individuals to rate themselves on a variety of feelings, such as friendly, bitter, trusting, lonely, cheerful, weary, sluggish, and energetic, using a scale that ranges from “not at all” to “extremely.”
Evaluation of the data is typically performed by a sports psychologist or other professional with experience using the survey instrument. By themselves, psychological tests like these aren’t enough to diagnose overtraining syndrome, but they may reveal trends that help assess an athlete’s risk level.
A multi-faceted testing and evaluation protocol is the best way to catch overtraining in its earliest stages. One of the best examples was created by two researchers, Jack Daniels, PhD, and Dick Brown, PhD, working with the well-known distance running group Athletics West. Following a slew of urine and blood tests that didn’t provide conclusive evidence of overtraining risk, they began to look for simple ways to assess all types of underlying physiological stress.
They asked their athletes to monitor morning resting heart rate, morning body weight, and number of hours slept per night, and compared the daily values to historical baselines for each individual. They theorized that a low morning heart rate (suggesting parasympathetic syndrome) or a high one (suggesting sympathetic stress) might indicate autonomic dysfunction, a hallmark of overtraining. Morning body weight would detect poor eating or hydration habits. Number of hours slept was a very basic way to get a glimpse of stress level and fatigue–too much sleep would suggest the body was yearning for more rest and recovery; too little sleep would reveal problems with anxiety, physical stress, or overall workload.
Daniels and Brown used the data to guide and adjust the athletes’ training programs. They created thresholds: If an athlete’s morning heart rate changed by 10 percent or more during the course of training, if their average sleep time changed by 10 percent, or if their weight fluctuated by three percent, that was interpreted as failure to recover adequately from hard workouts or races, or at least as a sign of a high stress level (whether directly related to training or not).
If one variable reached the threshold above or below the athlete’s baseline, training was monitored and/or reduced by 10 percent. If two variables raised red flags, training was cut by up to 50 percent. If all three variables were problematic, intense training was eliminated until the data returned to the baseline range.
Click here to read Part 2 Overtraining: Prevention and Intervention