Training too hard...?

Training too hard...?By Perry Stewart

We strive to achieve our fitness goals by continuously increasing the amount of training 'stress' placed upon our bodies, because we know that this process is integral to increasing fitness. But too much stress is counterproductive and can cause burnout. How can you avoid pushing yourself too far?

Putting stress upon our bodies when training (for example, increasing frequency, intensity and time of training) causes temporary fatigue and often results in performance decrements. However, like magic, after adequate rest, levels of fitness increase beyond those previously attained. This process is commonly referred to as supercompensation and applies to all effective training programmes (Figure 1).


Figure 1. The process of supercompensation: when appropriate training and adequate recovery is adhered to, positive adaptations occur, allowing the body to reach a higher level of fitness.

Stress: spot the difference

So progressive training stress is an effective means to an end but we need to get the balance right. If training load (and even competition stress) is consistently pushed beyond physical tolerance limits (excessive frequency, volume or intensity) for extended periods of time, with inadequate rest, it is likely to result in the onset of Overtraining Syndrome (OTS). This is often referred to as burnout or chronic fatigue. OTS is associated with many types of fatigue (metabolic, environmental, neural and psychological) and ultimately results in a decrease of performance and other counterproductive symptoms. The difference between functional overload/ supercompensation and non-functional overload/OTS only becomes apparent in the amount of time taken to recover. It is possible to recover from a state of acute overload within 1 week; however, if it has not occurred by then, it is possible that OTS is in full swing and recovery may take many months, with OTS recurring if athletes return to hard training too soon [1].

Rest and recover

In recent years more people have been training harder and more often, with less rest thinking they are achieving greater levels of fitness, stepping closer to their goal and getting there more quickly too. The probability is they are becoming overtrained, which will only result in a stale, non-productive psychological and physical state. This may be more of a concern for those who are simultaneously exposed to additional external stressors such as work, poor nutrition, menstruation, jet lag, ongoing illness and psychosocial pressures (from work, team, coach, family). The body responds to all types of stress in the same way and does not distinguish between them. It should be noted that professional athletes have regimented rest and recovery periods and protocols in place for a reason to reduce the risk of OTS and aid progressive physical development.

The signs and the science

Different athletes can tolerate different levels of training, competition and everyday stress depending on their level of health, fitness and lifestyle. Although there is no all-inclusive diagnostic test available as yet, we should identify and monitor potential signs of OTS. Each individual will react differently to overtraining, but typical symptoms are described in Table 1. OTS is effectively a long-term disturbance of homeostasis (maintenance of a constant internal state). It is not simply explained by a single cause, but is better understood as the failure of various physiological systems in coping with increased stresses and insufficient recovery (Table 2) [2].

Endocrine system (hormones)

There are numerous hormonal responses associated with OTS. One of these combines a reduction of testosterone (T) and an increase in the notorious stress hormone cortisol (C), a muscledegrading hormone. This results in a negative T:C ratio (low T:high C) causing a shift from anabolism (tissue growth) to chronic catabolism (tissue breakdown). This imbalance is likely to be in response to decreased muscle glycogen. Other reactions include decreased secretion of hormones from the pituitary gland (including growth hormone GH) and decreased tissue responsiveness to catecholamines (adrenaline, noradrenaline and dopamine). These responses result in decreased force production, energy availability, blood flow and reduced synthesis of other anabolic hormones.

Table 1. Symptoms of OTS


Chronic underperformance (diminished speed, strength, power, endurance)


Persistent high fatigue ratings


Persistent muscle soreness


Altered resting heart rate and decreased maximal heart rate


Sleep disturbances (occurring in 90% of cases: difficulty getting to sleep, nightmares, waking in the night and waking unrefreshed)


Reduced desire/motivation/competitive drive


Hormonal disturbances (affecting energy levels, physiological performance and mood)


Increased anxiety, depression and irritability


Depressed immune function


Increased incidence of injury


Loss of appetite


Weight loss/fat loss


Reduced libido

Table 2. Contributing factors to OTS


Sudden increase in training volume and/or intensity


Heavy competition schedule


Lack of planned/programmed recovery


Monotonous training schedule


High self-reported levels of stress, regardless of whether training-related

Nervous system

The effect of chronic neural fatigue can have various negative outcomes, including an inability to perform high-intensity exercise, eg, reduced maximal heart rates during/after training and a failure to activate fast-twitch muscle fibres, reducing total power output and impacting upon speed and power of movement. This imbalance within the autonomic nervous system will also reduce the ability to effectively relax. These neural responses to OTS are concurrent with counterproductive hormonal effects, eg, reduced tissue response to adrenal hormones such as catecholamines.

It is inappropriate to view the physiological responses as independent components, but better to see them as an interaction between the endocrine and nervous systems (ie, neuroendocrinology) which disrupt homeostasis.

Immune system


Figure 2. Cycle of recurring minor infections (adapted from Budgett, 1998 [1])


Figure 3. Overtraining and/or under recovery, leading to OTS

It is thought that intensive exercise and competition and inadequate rest/recovery increases the risk of infection, which is partly due to reduced glutamine levels and high levels of circulating cortisol. Glutamine is an amino acid essential for white blood cell function. Therefore, reduced glutamine levels result in depressed immune function and increased risk of infection, especially upper respiratory tract infections (URTI). Those in an overtrained state are likely to repeatedly become ill, if full recovery from OTS is not achieved (Figure 2).

Tactics for prevention

Athletes are likely to ignore such signs as fatigue, long-term muscle soreness and depression until performance is chronically affected (Figure 3). Therefore, monitoring physical and psychological state will help detect early signs of OTS. Use of training diaries/logs is highly recommended to record daily and weekly training loads, perceived levels of exertion, mood and sleep patterns. A study by Morgan et al. [3] found that increasing training when the mood state was high, and reducing training when mood state was low, reduced the incidence of OTS from 10% to 0%. Mood states are often assessed by a psychological scale known as the Profile of Mood States (POMS) and are used frequently by professional sports clubs. It is also essential to have a structured programme with appropriate amounts of rest and planned recovery strategies in place.

Handle with care

Rest days/periods within training programmes and regeneration strategies are central to recovery and consequently long-term physical development. The British Medical Centre found that both physical performance and mood improved with 5 weeks of physical rest [4]. Also, completing low-level (non-sport specific) exercise has been shown to speed recovery. This should be a gradual process with intensity kept low until a rise in intensity can be tolerated. Although it is difficult to predict how long it takes for the symptoms of OTS to resolve, with careful rest and regeneration, it is suggested that recovery can take 612 weeks [4].

Key points

  • OTS is a condition of chronic fatigue which results in underperformance, decreased psychological wellbeing and increased vulnerability to infection.
  • Rather than having a 'sole' cause, it is likely to result from a combination of physical (intensive training and competition schedule) and psychosocial stressors (coach, family, and peer expectations; monotony in training; school or work demands; and environmental factors).
  • OTS is very difficult to diagnose, with correct diagnosis often emerging retrospectively so a careful monitoring process can help prevent onset, whilst management is simply to rest. Scheduling regeneration and recovery routines in every programme will allow athletes to completely recover at least once per week.
  • Symptoms of OTS should resolve within 612 weeks; however, the recovery process should not be rushed or OTS may persist for a considerable time.

References

1. Budgett R. Fatigue and underperformance in athletes: the overtraining syndrome. Br J Sports Med, 1998, 32, 107110.

2. Hooper SL, Mackinnon LT. Monitoring overtraining in athletes: recommendations. Sports Med, 1995, 20, 321327.

3. Morgan WP, Brown DR, Raglin JS et al. Psychological monitoring of overtraining and staleness. Br J Sports Med, 1987, 21, 107114.

4. Koutedakis Y, Budgett R, Faulmann L. Rest in underperforming elite competitors. Br J Sports Med, 1990, 24, 248252.

Correspondence

Perry Stewart is a Strength & Conditioning Coach and Lecturer at the London Sport Institute.

Please contact Perry with your comments and queries:
Email: p.stewart@mdx.ac.uk


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