No Short-cuts: Recover or Else!

Supercompensation is exposure to mild stress over time with adequate recovery periods. The recovery periods restore the body to normal and facilitate tissue repair. This allows for physiological adaptation and the strength to cope with the stressors of exercise^(1,5). The training and supercompensation process can be broken down into four phases (see figure 2):

• Phase 1—Training: Athletes begin introducing training stimuli higher than the body is previously used to (e.g., structured training). This stress prompts fatigue, which is reflected in declining performance.
• Phase 2—Recovery: Declining performance demands that the athlete introduce recovery in some form, such as active rest, recovery sessions, or simply taking a day off completely. Proper recovery and nutrition allow energy stores and performance to return to the original baseline fitness.
• Phase 3—Supercompensation: This is when supercompensation comes into play. After adequately recovering from a workload that the body was previously not suited to withstand, the body’s predictive and responsive nature builds itself in anticipation of the next expected challenge, tricking the body into becoming suitable to withstand the next effort based on the previously experienced challenge in phase one.
• Phase 4 — Decline of fitness (preparedness): Naturally, all good things must end. Well, ideally, not for long. When athletes reintroduce training, the stimulus should frame the height of the supercompensation effects to maximize benefits. The process thus repeats itself. As time spent implementing the supercompensation model increases, so will their fitness. 

Sleep: Critical, not Optional

Recovery of the central and peripheral nervous systems is critical⁽²⁾. Fatigue takes place in both of these systems during exercise. Sleep assists in the recovery of these systems. Athletes must consider quality, quantity, and time. The brain regulates all physiological systems, so sleep is critical in central nervous system recovery. Unloading the nervous system allows it to focus on restoration. Sleep remains the best recovery tool available to athletes. Clinicians must continue emphasizing its importance as athletes will focus on what clinicians value and spend time discussing.

Recovery Nutrition

Fluids are critical for restoring several systems following exercise, including the cardiovascular, renal (kidney function), and nervous systems. Through sweating, athletes lose plasma volume and their stroke volume decreases, increasing the heart rate. Therefore, replacing fluid soon after exercise assists in increasing plasma volume, thus stroke volume, and allowing our heart rates to lower, restoring cardiac output and returning the cardiovascular system to normal. Furthermore, fluids are important for renal function. The brain needs a constant level of blood glucose, and when dehydrated, this is affected, thus affecting our cognitive function. Consider, too, that drinking water only may further dilute the plasma, causing the loss of more water than taking in, thus the importance of replacing electrolytes (sodium and potassium) when hydrating during recovery.

Combining several dietary strategies will likely be of more significant benefit than one strategy in isolation. Nutritional strategies to enhance performance include optimizing macronutrients, micronutrients, and fluid intakes, including their composition and spacing throughout the day⁽⁶⁾. Muscle glycogen is used during exercise. As the intensity and duration of exercise increase, so does muscle glycogen use. It is used more rapidly when training in the heat and untrained individuals. Replacing carbohydrates soon after exercise is important, especially if the next session is the following or the same day. Insulin and glucose receptor sensitivity is increased directly following exercise, an optimal time to restore muscle glycogen. Muscle damage affects muscle glycogen resynthesis so that a replacement will aid the muscle damage during high-stress exercise efforts. Generally, practitioners advocate for simple rather than complex carbohydrates in the first 24 hours, but this depends on the training objective and schedule^(6,7).

Protein intake is vital to repairing skeletal muscle and connective tissue. One common source is whey protein, which has good amino acid bioavailability. Furthermore, combining protein and carbohydrates is beneficial^(6,7).

Adjunctive Recovery Tools

There are many tools that athletes may use to facilitate their recovery, such as stretching, compression, ice baths, massage, ultrasound, and neuromuscular electrical stimulation. While all these modalities have some evidence, none stand out. Compression garments, massage, and ice baths appear to impact muscle soreness, but this is a subjective quality, so removing the subjective from the objective benefit is tricky. There is limited support when looking at the objective benefits, such as muscle strength and range of motion⁽⁴⁾. However, perhaps the subjective benefits are critical to overall athlete well-being. Clinicians must advise against using non-steroidal anti-inflammatory drugs (NSAIDs) for recovery as they may interfere with the muscle resynthesis process⁽⁴⁾.

Active vs. Passive Recovery

Active recovery is the low-intensity exercise or activity performed after a strenuous workout or athletic event. Passive recovery involves complete rest or minimal physical activity following intense exercise or athletic performance. Active recovery (cool-downs) are generally ineffective in enhancing same-day and next-day sports performance, preventing injuries, or improving most markers of psychophysiological recovery⁽⁸⁾. Although they can accelerate blood lactate recovery and possibly aid cardiovascular and respiratory recovery, their practical relevance remains unclear⁽⁸⁾. Furthermore, they don’t significantly reduce muscle soreness or muscle damage or improve neuromuscular function and may interfere with muscle glycogen resynthesis⁽⁸⁾. Despite these findings, many athletes and coaches perceive active cool-downs as beneficial, which could be due to placebo effects or personal preference rather than actual physiological benefits.

Endocrine Recovery

The immune system influences other physiological systems, including the endocrine system. Changes in the immune system thus influence the hormonal profile⁽³⁾. The immune system is also closely linked to sleep. This system regulates body temperature and appetite and plays a role in muscle damage due to controlling inflammation. Chronic inflammation results in delayed muscle repair, which increases injury risk. Furthermore, immune system suppression during periods of high training stress can increase the chances of typical respiratory infections⁽⁴⁾.

Conclusion

Recovery is multifaceted. Each athlete needs to optimize their hydration, nutrition, and sleep routine. Experimentation is critical but should be done using the latest evidence without compromising long-term health. There are no shortcuts in training and recovery, and athletes and clinicians must prioritize their recovery process to ensure optimal performance – particularly as the races get longer and the demands unexplored.

References

1.    J Strength Conditioning Research. 2008. 22 (3) 1015 – 1024
2.    Sports Med 2006. 36 (9): 781-796
3.    J Appl Physiol 2017. 122:  531 – 532
4.    J Appl Physiol 2015. 119: 172–189
5.    Sports Med 2011. 41 (10): 861-882. Athletic Development Vern Gambetta
6.    Open Access Journal of Sports Medicine 2015. 6 259–267
7.    J International Society of Sports Nutrition 2022. 19, NO. 1, 623–637
8.    Sports Med (2018) 48:1575–1595