– David Joyce –
With the start of the major northern hemisphere football leagues only a matter of a few short weeks away, preparations are now being fine tuned by sport science teams around the globe. We know that it’s vital to start the season well as momentum is critical, and so we really want to hit the ground running. This is particularly the case in American Football where a slow start to the season can be fatal to a team’s chances.
From an athletic preparation perspective, the preseason allows exposure of the players to eustress, a positive process of overload. This is the basis for all training and is critical to stimulate the body to adapt and therefore improve. Should training exceed the body’s ability to adapt, we hit distress, a maladaptive state that is the basis of overtraining.
I believe that we are all very good at the training part of it. Where I think there is still scope for improvement is the recovery side of the ledger.
Athletic performance is maximised when the athlete enters an event under a degree of competitive stress but in a physiologically and mentally rested state. As such, optimal recovery strategies will have both physical and psychological domains. This understanding should underpin all regenerative protocols.
Before we discuss these strategies, we must first examine the stresses the players will undergo in a little more detail.
Physical stress from training and competition
The important thing to understand is that the concept of recovery needs to encompass all the various stresses that an individual has experienced. Each person is likely to be stressed differently and as such, there cannot be a perfect recovery recipe. Genetics play a large role in accounting for the magnitude of response to resistance training and it is likely that there is a genetic basis to recovery as well.
It is essential that the recovery strategy be individualized to the player and also according to the load that that player encountered in a particular game. We need to consider the toll that body contact (frequency and magnitude) imposes, as well as the frequency and magnitude of high speed running and mechanical load (accelerations, decelerations, direction changes).
These indices are largely influenced by the position played and the style of the game. If we take soccer as an example, high intensity running (>5.5m/s) distance is much greater when both teams play an open counter-attacking game, whereas the mechanical load imposed by short sharp decelerations may be greater in a more cagey tight game. Obviously, this is where pragmatic interpretation of GPS is critical.
Factors that need to be considered when individualizing a recovery programme
1. Distances run during the game
In soccer, an elite midfielder in soccer may cover almost 14km during a game whereas a centre back is likely to traverse only around 11.5km
2. Number of sprints during the game
Again, we need to look at positional differences here, but also changes in sprint meters compared to what the player is used to.
3. Number and magnitude of decelerations and changes of direction
Body load is much greater when the number of decelerations / changes of direction is high due to the eccentric stress placed on the lower limbs.
4. Body contact
Collisions can cause substantial muscle damage and both the size and number of the collisions in a match / training session needs to be considered
5. Emotional stress
It is vital to remember that we are dealing with human beings, not robots. For example, the emotional stress that a striker who has just scored the winning TD is likely to be quite different to that experienced by a quarterback who had a nightmare game to gift a win to their opposition. These stresses need to be recovered from.
If a player has sustained an injury, they may not necessarily be able to complete the same recovery programme as their team mates.
An older player’s body takes longer to recover following a game.
Physiological load following high intensity exercise
There are limited studies on elite footballers as most studies on recovery strategies have been performed on untrained populations. As such, many of the effects of intense competition that have been published may not actually apply to the group of players that we are discussing in this paper. The three physiological sequelae of intense competition that are relevant to this population are:
The intermittently intense nature of the soccer has been shown to elicit sweat rates of between 1500-3750ml during a 90 minute soccer match. Performance decrements have been shown to occur at dehydration rates of less than 2% and so it is necessary to replenish fluids during and after the match, well as after training. This can be even greater in American Football due to the clothing and protective equipment worn, especially in the early rounds where temperatures are higher.
Glycogen is the primary fuel source during a football match. In fact, it is thought that the development of fatigue during a match is related to the development of fatigue. This is demonstrated by a reduction in running distance and fewer episodes of high intensity running. As long ago as 1973, Swedish researches showed that players with low initial glycogen content covered 25% less distance during a match compared with players with high glycogen levels. It is therefore necessary to ensure that players enter a match with high glycogen reserves and have a supply at half time.
The most common injury ‘complaint’ in football is muscle soreness as a result of direct contact. These contact injuries do not necessarily make it onto the injury lists that are published in official reports because they may not be severe enough to stop a player from playing in the following match. They are however, enough to reduce subsequent training performance. The structural damage that occurs can be quantified by the presence of enzymes and muscle proteins in the blood, in particular, creatine kinase (CK). Structural damage and hence the presence of elevated CK concentrations following a football match is attributed to eccentric loads and direct trauma (in particular the paraspinal, gluteal, quadriceps and calf muscle groups). Significant performance decrements have been demonstrated when CK levels are elevated.
With these factors in mind, it becomes easy to see why an ‘off-the-peg’ recovery strategy cannot be considered best practise. There are however some ‘non-negotiables’ when it comes to match recovery and these need to be followed irrespective of the individual. Much research has gone into recovery protocols all with the aim of gaining that ‘extra 2 per cent’. This is fine, so long as the 2 major factors that influence recovery (the main 98%, if you like) are in order. These 2 factors are:
Precisely what each team will use to achieve this will be determined by sponsorship deals each national federation have in place but in general, a carbohydrate and electrolyte blend sports drink will be the most commonly used drink. Hydration status will be monitored daily by most national sport science teams, with fines likely to be issued to players found to have unacceptably high osmolarity readings.
High pre-event muscle glycogen levels are thought to be essential for optimal performance in sports that entail high levels of sustained, high intensity work and it has been said that the restoration of muscle glycogen levels post-exercise is the most important factor in terms of recovery time. It appears that the greatest depletion in muscle glycogen occurs in the first half of the match and so a high GI CHO-rich drink is recommended during the interval. Following the match, it is recommended that 75-90g of CHO are ingested immediately within 2 hours of the final whistle then at regular intervals up to 5 hours afterwards although, clearly this will depend on the time the game finishes. Often, players have difficulty eating immediately following a match and so a CHO-rich drink is often used as this allows for rehydration as well.
Adequate sleep is vital for both physiological and psychological restoration. Indeed, it may in fact be the most important recovery mechanism available to us. Whilst high quality sleep studies involving elite athletes are few, in general sleep deprivation has been shown to have the following effects:
• Impaired immune function with increased incidence of illness
• Delayed reaction times and impaired decision making capacity
• An increase in perception of effort of repeated exertion efforts
• Decreased growth hormone synthesis, impairing muscular repair
• Increased cortisol release
• Delayed glycogen store replenishment
As a result, teams should make arrangements to optimise the sleeping environment of their players, especially when in hotels. Generally speaking, players have difficulty getting to sleep until after 2 in the morning following an evening game due to all the mental and emotional stress from the match. This is not so much of an issue in the short term, because the players will be used to dealing with this when playing evening games. Where it becomes an issue is when a player starts to accumulate a sleep ‘debt’.
OTHER RECOVERY STRATEGIES
A myriad of other modalities have been proposed to help with recovery following intense matches and we will probably see all of them employed in one way or another during the course of the tournament. In fact, there appears to be scant scientific evidence that supports many of the interventions and so I will focus only really on the most common recovery methods that we see in professional football.
Ice baths will be one of the most commonly used interventions following a match. Whilst their use is debated following training due to the possibility that they may retard the adaptive humoral / molecular response to intense exercise, cold water immersion does have analgesic effects and may be beneficial in reducing the muscle damage we see following a match. Contrast therapy may also be used. This is usually a 20-30 minute programme of movement in warm water (37-43 oC) for 3-4 minutes, followed by cold water (12-15 oC) for 30-60 seconds. Ice baths may also help us sleep.
Massage is one of the most commonly used recovery modalities used in elite football. The evidence available to date does point to massage being effective in reducing perceptions of muscle soreness although its use in enhancing muscle function and athletic performance is less clear. In addition, massage may have strong relaxation effects, which is very important in reducing psychological stress. It is possible that vigorous post-match massage could extend any trauma and so its application should be under the supervision of the sports medicine team.
Pool recovery sessions
Hydrostatic pressure may be beneficial in reducing the symptoms of muscle damage and general fatigue following a match. It does not appear that the temperature of the water is too important. An example of a typical pool recovery programme is:
The 100-point menu
Knowing that recovery is individual-specific, we have found that the best option is to provide a “menu” of modalities. Immediately post match, the players need to accrue 100 points from this menu, knowing that alcohol is an automatic deduction of 25 points that they need to make up from elsewhere. Whilst we discourage the players from going out boozing, we’ve found that an education process is much more effective than an outright ban.
The following day and during the week, there are a few more items on the mental. You’ll see that we ‘reward’ group recovery with more points, due to the well-documented positive endocrine effects of social interaction with friends and family.
The process of recovery allows the body to adapt, repair and replenish nutrients. The effectiveness of the recovery strategies employed by the various high performance support teams will be major determinants of their team performing to their maximum. In essence, the major factors that need to be considered are individualized strategies for glycogen and fluid restoration following matches and training sessions, as well as sleep. This is in addition to recovery from the psychological and emotional stresses that inevitably occur during such high-stakes competitions!
David Joyce is the Head of Athletic Performance for Western Force in the Southern Hemisphere’s Super Rugby competition – the toughest club rugby competition in the world. He holds Masters degrees in both Sports Medicine and Strength and Conditioning and lectures on the Masters of S+C at Edith Cowan University and is a member of the Team EXOS International Education Team. He is the editor and author of High Performance Training For Sports (Human Kinetics).