Defining Recovery - why we train hard and recover harder.

‘The main role of recovery is to help athletes adapt faster to training by reducing any performance fatigue that they experience, so they can bounce back and be ready for the next session or event.’

Calder, A 2004, 'Recovery and Regeneration' Faster Higher Stronger, vol. 22, pp. 12-15

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Physiology behind fatigue & recovery

Fatigue is a complex and multifaceted phenomenon that has a variety of possible mechanisms. To date a multitude of descriptions exist, however there is a lack of cohesion as to a widely accepted and researched definition of fatigue, making its measurement equally problematic.

Acknowledging the complex and intertwined psychophysiological nature of fatigue is perhaps the best conceptual step we can take to furthering our understanding xiv. A definition provided by Enoka and Deuchateau (2016) eloquently captures this complex nature by describing it as “a disabling symptom in which physical and cognitive functioning is limited by interactions between performance fatigability and perceived fatigability”. From a scientific point of view, fatigue can simply be described as:

‘The disruption of physiological and psychological systems that leads to a decrement in athletic performance.’

Firstly, it is important to determine what type of fatigue the athlete needs to recover from. After determining each type of fatigue, we need to understand and recognise the behaviours or actions an athlete is exhibiting to match the type of fatigue. We can then provide a recovery plan to assist the athlete with their recovery. There are four commonly accepted types of fatigue :

1. Neurological

2. Psychological

3. Metabolic

4. Environmental

1. Neurological Fatigue (nervous system)

Neurological fatigue is an exercise-induced reduction in the ability to produce force or power with a muscle or muscle group and can be broken down into two main components; central (neural) & peripheral (muscular).

Muscle fatigue is defined as loss of the capacity for generating force and/or velocity resulting from muscle activity under load which is reversible by rest (NHLBI, 1990).

1. Peripheral Nervous System (localised force production) - processes at or distal to the neuromuscular junction is known as peripheral fatigue (localized to the muscle or muscles you’re working). The peripheral nervous system puts your brain in touch with the physical environment and allows it to respond.

2. Central Nervous System (drive/motivation) - processes within the central nervous system (CNS) that reduce neural drive to the muscle can also contribute to the decline in force or power and compromise performance. This phenomenon is known as central fatigue. The Central Nervous System (CNS) integrates sensory information that the peripheral nervous system collects from all over the body, responding to it by coordinating both conscious and unconscious activity. 6 Simply put, the brain isn’t able to send messages to the body as quickly thus reducing the athletes ability to perform a given task.

Recognising Neurological Fatigue

Peripheral Nervous System Fatigue can occur after short high intensity sessions (hard strength training session, plyometrics) or after long lasting but low intensity sessions (low intensity steady state workout) and is expressed by a reduction in localised force production.

Peripheral Nervous System Fatigue can be recognised by:

• Heavy legs and/or feet

• Feels constantly tired and sore

Central Nervous System Fatigue can occur if the athlete has an inadequate diet (low blood glucose levels), lack of sleep, is injured or consistently overtrains without adequate recovery. Central Nervous System Fatigue can be recognised by:

• Regularly overtraining to the point of exhaustion, this can cause your brain to become chronically tired - Lack of drive and motivation

• Poor skill execution of things you can normally do without an issue

• Forgetfulness and lack of focus - Persistent fatigue that interferes with workout

• Anxiety, irritability, and other emotional issues

• Compromised immune system making you feel sluggish and sick Testing of neurological fatigue

• Performance based testing of neurological fatigue include grip strength measures, maximal jumps, overground sprints and submaximal cardiovascular

Testing of neurological fatigue

• Performance based testing of neurological fatigue include grip strength measures, maximal jumps, overground sprints and submaximal cardiovascular tests. One of the most commonly reported and applied jump assessments in current literature is the counter-movement jump (CMJ).

• Self-report forms

Recovering from Neurological fatigue

Recovery can be achieved by:

1. Peripheral Nervous System Fatigue - Rehydrate & refuel - Contrast Water Therapy - Warm bath - Infrared Sauna - Massage

2. Central Nervous System Fatigue - The most important factors in overcoming CNS Fatigue are rest and recovery - Prioritize adequate recovery time between workouts - High-intensity workouts must always be balanced with enough recovery days - Reduce stress - Improve nutrition & sleep

2. Psychological Fatigue (emotional and stress factors)

Psychological fatigue, commonly described in the literature as Mental Fatigue (MF), can be described as a cognitive load that accumulates from external stimuli varying from short to long term exposure. This exposure can thus cause an imbalance between psychological demands and resources. When this imbalance is maintained for long periods of time it leads to an evaluation of perceived overload and learned defencelessness.

• Emotional
  Hormonal
  Relationships
  Loss (friend, relative, pet)

• Social
  Home life
  Relationships
  Financial

• Stress
  Competition stress
  Exam and schoolwork pressure
  Lack of control (lockdowns, COVID restrictions, venue and schedule changes)

Recognising Psychological Fatigue

• Low motivation

• Low concentration

• Decreased alertness

• Increase negative self-talk

• Change in interpersonal relationships

Testing psychological fatigue

• Self-report forms

• Visual Analog scales

• Mood assessment

• Psychomotor Vigilance

Task Recovering from Psychological Fatigue

• Yoga

• Breathwork, mediation, visualisation

• Relaxation (music, movie, reading, socialisation)

• Infrared Sauna

• Resilience Building Skills - Debriefing

3. Metabolic Fatigue (energy stores)

Metabolic fatigue is a characteristic muscle response to intense exercise that has outstripped the rate of ATP replacement and is the result of several demanding training sessions or events lasting more than one hour, several sessions a day or over several days.

Recognising metabolic fatigue

Metabolic fatigue can be identified when:

• the athlete fatigues sooner than is normal for that athlete

• struggles to complete the session or event

Testing metabolic fatigue

• VO2 Max Testing

• Counter Movement Jump Force Recovering from metabolic fatigue

Metabolic Fatigue can be recognised by:

• Restoring fluid & fuel stores

• Increase the deliveries of these stores to fatigued muscles (hydrotherapy, active recovery)

4. Environmental Fatigue (travel, climate, schedule change)

Environmental fatigue can be defined as a disruption or change in an athletes training, competition or living environment. This commonly occurs as a result of travelling or a change in climatic conditions. This can be a constant challenge for coaches and athletes.

Recognising Environmental Fatigue

• Inconsistent wake-up/sleep times (circadian disruption)

• Changed mealtimes leading to hunger or dehydration

• Fluctuation or change in altitude

• Fluctuation or change in temperature

Testing environmental fatigue

• Self-report forms Recovering from Environmental Fatigue

• Re-structure & plan schedule changes as quickly as possible

• Focus on things you can control

• Plan naps

• Prepare food & hydration

• Source travelling options (mobile recovery options)

The Implications of Fatigue on Sports Performance

All factors of fatigue have been shown to impact multiple aspects of individual and team sporting performance, including execution of technical, tactical and physical variables xii. Given this information, it is imperative for coaches, support staff and athletes to consider implementing recovery schedules that assist in optimising the time between onset of fatigue and adaptation.

Furthermore, it is critical for coaches and high-performance teams to adjust these plans based on how the athlete is adapting or coping with the imposed training schedule and competition demands. Whilst coaches and high-performance staff aim to control as many aspects of training and competition as practically possible, it is inevitable that an athlete’s personal life and individual circumstances can induce an onset of any one of the previously mentioned mechanisms of fatigue.

Conclusion

The 4 commonly accepted mechanisms of fatigue are Neurological, Psychological, Metabolic and Environmental. The current research on fatigue indicates that there is a significant impact on multiple aspects of individual and team sporting performance. The most common form of fatigue assessment to date seems to be through self-report measures due to the ease of practical application, particularly in a high-performance setting where an athlete’s day-to-day demands are high.

Whilst it is important to employ a broad understanding of fatigue to sporting performance it must also be considered that a high variability will exist when considering the type and the duration of task the athlete is undertaking. We understand that it is important for us to be able to quantifiably measure fatigue and that recovery plays a vital role in the process of improving an athlete’s performance over time.

Now that we have defined these types of fatigue and developed an understanding of some key indicators, stay tuned for future resources on the most up to date methodology in regards to tracking fatigue and inevitably prescribing the appropriate recovery schedule.