Practical nutritional recovery strategies for elite soccer players when limited time separates repeated matches

The main focus immediately after a match is to replenish both liver and muscle glycogen stores through ingestion of adequate carbohydrate. For optimum glycogen resynthesis it is a prudent strategy to consume carbohydrate immediately after a game as glycogen-synthesising enzymes are most active during this time [28]; thus there is a potential ‘window of opportunity’ that players should seek to take advantage of. Indeed, when compared to immediate carbohydrate ingestion, delaying carbohydrate feeding until 2 h after exercise can result in lower muscle glycogen concentrations by 45% when assessed 4 h post-exercise [28]. Thus players should be encouraged to consume a recovery drink and/or snacks as soon as possible after a match ends. This can be achieved practically by providing several opportunities to consume carbohydrate-electrolyte drinks on the pitch, in the media suites for post-match interviews and in the changing rooms.

The amount and frequency of carbohydrate ingested is an important factor to consider during the immediate recovery period (i.e., within 20 min of match-play). Generally, the ingestion of 1–1.5 g·kg⁻¹·h⁻¹ of carbohydrate has been shown to benefit maximal glycogen resynthesis in the first 4 h post-exercise [29]. Therefore, based on the upper limit of this recommendation, an 80 kg player would be advised to consume ~96 g of carbohydrate per hour in the hours after a game finishes, with a particular emphasis on achieving such rates during times of fixture congestion. Furthermore, during this initial stage of recovery, a strategy of frequent ingestion of carbohydrate (i.e., every 30 min) has been shown to induce greater glycogen resynthesis rates compared to a less regular (i.e., every 2 h) protocol [30]. Similarly, adding 0.2–0.5 g⋅kg⁻¹⋅day⁻¹ of protein to carbohydrate has been shown to stimulate glycogen resynthesis to a greater extent than consuming carbohydrate alone [31] but only when carbohydrate intake is less than 1.2 g⋅kg⁻¹⋅day⁻¹. It has been suggested that high glycaemic index (GI) foods may be preferable over moderate and low GI foods when the goal is to restore glycogen as quickly as possible [32‐34].

The consumption of adequate quantities of carbohydrate in this post-match phase is likely the most beneficial aspect of carbohydrate recommendations. Accordingly, support staff should seek to provide food and drinks that are both tempting and practical to eat (see Tables 1, 2 and 3 for practical examples). Food options should be promoting a desire to eat such that sufficient amounts in agreement with recommended values are realised as a loss of appetite may exist in some players in the time shortly after matches. Support staff should ascertain the types of foods players are likely to eat in this immediate recovery phase as players may have individual cultural preferences.

The type of carbohydrate recommended in the immediate phase of recovery is high GI foods (see Table 1 for examples). High GI sources are proven to accelerate muscle glycogen resynthesis rates in the first 6 h of recovery compared to low GI sources, most likely due to malabsorption of low GI carbohydrate-rich foods [35]. However, the effect of high GI carbohydrate meals on subsequent soccer-specific performance still remains unclear, with no difference observed between high and low GI diets on endurance and sprint performance 24 h after 90 min of intermittent exercise [36]. It is the player’s preference that should drive the decision as to whether solid or liquid forms of carbohydrate are ingested as both appear equally effective for muscle glycogen restoration [37].

From a practical perspective, the consumption of high amounts of carbohydrate required from food sources can bring about gastrointestinal problems so it is important that players have access to a mixture of fluid and solid foods to prevent such issues [38]. There is evidence to suggest that multiple transportable carbohydrates in the form of glucose and fructose increases gastric empting and fluid delivery compared to glucose only [39, 40] thus drinks provided at the end of the match should contain multiple transportable carbohydrates. Due to the fact that liquid carbohydrate solutions can contribute to rehydration in conjunction with exogenous carbohydrate supply, carbohydrate-containing fluids may be more preferable for immediate ingestion when compared to solid foods. A selection of high GI drinks and snacks should be readily available in the changing room after a game (refer to Table 1 for a selection of recommended carbohydrate foods).

The co-ingestion of protein with carbohydrate has proven beneficial in the context of glycogen resynthesis when sub-optimal carbohydrate amounts were consumed via an augmentation of postprandial insulin secretion [41]. A similar increase in glycogen synthetic rate has been observed when 0.4 g·kg⁻¹·h⁻¹ of protein was added to 0.8 g·kg⁻¹·h⁻¹ of carbohydrate relative to ingesting 1.2 g·kg⁻¹·h⁻¹ of carbohydrate alone [30]. The inclusion of protein to sufficient carbohydrate intakes is advisable to aid glycogen re-synthesis and enhance muscle tissue repair [42] (see Table 1). As milk or flavoured milk naturally contains a mixture of carbohydrate and protein, it may positively influence recovery and is likely a good choice of recovery beverage for lactose-tolerant players [43, 44].

During a congested week (see Fig. 1), it is important to implement a carbohydrate feeding strategy that not only replenishes endogenous fuel stores but also seeks to fully maximise muscle glycogen concentrations in preparation for the next game as the 48 h post-exercise recovery period may also coincide with the 48 h period leading into the subsequent match. Optimal performance can largely be attributed to carbohydrate availability [45]. Notably, players consuming a high carbohydrate diet (10 g·kg⁻¹·day⁻¹ for one week improved repeated high intensity intermittent performance compared to players on a mixed diet (5 g·kg⁻¹·day⁻¹carbohydrate; [46]. However, recent soccer-specific literature has failed to report an increase in glycogen concentrations above pre-match levels 48 h after a game, despite the ingestion of a high carbohydrate diet of up to 10 g·kg⁻¹·day⁻¹ [11, 47]. Similarly, a carbohydrate rich diet with whey protein ingestion failed to increase glycogen resynthesis when compared to a normal diet [25]. Therefore, supercompensation of muscle glycogen concentrations has yet to be reported 48 h after a game; a response which is typically seen in sports such as cycling [48]. This may be attributed to the high eccentric component involved in soccer-specific movements with resulting muscle damage impairing glycogen resynthesis during recovery [47]. Fast twitch-muscle fibres in particular, had lower glycogen content in comparison to slow twitch fibres 48 h after a high carbohydrate diet [25]. Practically this could have implications on recovery time scale for the more ‘explosive’ players in the team who have a higher composition of these fibres in the muscle but more research is warranted in this area.

While carbohydrate recovery strategies in the 48 h after a game are less clear than endurance sports, it is difficult to recommend exact guidelines for the amount for optimal recovery. Nevertheless, a general guideline of 6–10 g·kg⁻¹·day⁻¹ is a prudent aim for elite soccer players in the days of muscle glycogen recovery/loading. This could be achieved through 3–4 main meals and regular carbohydrate snacking interspersed throughout the day (Table 1). This nutritional approach, coupled with acutely modulating training intensity and duration, will likely increase the availability of carbohydrate in the body in a week that involves 3 games in a 7-day period.

Exercise increases both muscle protein breakdown and protein synthesis [49]. However, prolonged periods of negative protein balance may result if synthesis rates are not periodically elevated through dietary protein consumption; a scenario that the elite player should seek to avoid when fixtures are congested. The effects of a high amount of eccentric actions during match-play, as well as impacts from tackles and challenges with the opposition, results in impaired muscle function [50] that must be restored. To repair damaged muscle fibres and stimulate molecular adaptation, the post-match nutrition strategy should target the promotion of protein synthesis and attenuation of muscle breakdown. It has recently been shown that consuming 40 g of protein rather than just 20 g after exercise stimulates greater myofibrillar protein synthesis irrespective of the lean body mass of the individual [51]. Thus, the consumption of 40 g of protein as a post-match serving seems to enhance protein synthesis rates relative to smaller doses examined previously [52, 53].

Ultimately, protein-requirements should be achieved through high quality protein meals and snacks in the diet (see Table 2). However, appetite can sometimes be suppressed following high intensity exercise so liquid supplements can be provided as an alternative for players who cannot eat solid foods. In this respect, whey protein has proven to be a superior source in comparison to soy or casein when taken in isocaloric amounts [54]. This is due to its quicker digestive properties and rapid absorption kinetics. It also contains a high proportion of the key amino acid leucine, which is believed to be the main trigger for muscle protein synthesis augmentation [55]. Animal proteins such as chicken, beef and fish can also contain a high amount of this key amino acid.

Using protein supplements can be a convenient strategy for many athletes. As previously discussed, whey protein is superior to soy and casein sources because of its rapid digestion and higher leucine content [54]. That said, plasma aminoacidemia is higher following the ingestion of liquid versus solid protein sources [56]; therefore, post-game benefits of fluid-based protein ingestion may be realised. A ready to drink formulation may also have a greater practical appeal to players post-game.

Leucine is an essential amino acid which through the activation of mammalian target of rapamycin complex (mTOR) signalling pathway may in part attenuate the decrease in muscle protein synthesis after exercise [57]. It is present in high quality proteins and it has been reported that 3 g of leucine is capable of enhancing muscle resistance to insulin through muscle protein synthesis activation [58]. This amount can be obtained through dietary sources such as 140 g of chicken, 170 g of fish or 20–25 g of whey protein, but it can also be ingested as an isolated supplement.

After the initial intake of protein in the hours after a game, it is important for the player to continue maximising their protein synthesis over subsequent days to support recovery and adaptation. Players should be strongly encouraged to include sources of protein in their meals with the amount of protein required daily being dependent on the severity of the player’s physical programme. Although a sedentary male is recommended to consume 0.8–1.2 g·kg⁻¹·day⁻¹ of protein to achieve nitrogen balance, elite soccer players will require more to support their intensified workload during busy periods. For example, a daily protein intake in the range of 2.3 g·kg⁻¹·day⁻¹ body mass (BM) has shown to better maintain muscle mass when there is an energy deficit [59]. Furthermore, when protein intake was elevated from 1.5 g·kg⁻¹·day⁻¹ to 3 g·kg⁻¹·day⁻¹ immune function was better preserved, resulting in less upper respiratory tract infections and an overall tolerance of strenuous training [60].

Although there is an absence in research relating to daily protein intake for elite players during intensified periods, it would be prudent to recommend that at least 1.5–2 g·kg⁻¹·day⁻¹ of body mass of protein is consumed in order to cope with demands of a congested fixture period. In order to achieve this amount, an 80 kg player would require approximately 120–160 g of protein per day. Good quality of protein sources such as meat and fish contain around 25 g per 100 g and other sources such as milk, nuts, yoghurt, and beans can contribute to this amount. It has been reported that in elite academy players (U18 s) that there is a skewed distribution of protein intake where more protein is consumed for dinner (~0.6 g·kg⁻¹) and lunch (~0.5 g·kg⁻¹) in comparison to breakfast (~0.3 g·kg⁻¹) [61]. Thus, in terms of the amount of protein consumed over the day, meals or snacks should be divided into 6 × 20–25 g (120–150 g of protein) feedings interspersed by 3 h for stimulating maximal protein synthesis throughout a 24 h period [62].

Intense exercise during a game leads to an increase in metabolic heat production which can raise muscle and rectal temperature to above 39 °C [63]. The main physiological mechanism to lose heat from the body is to evaporate sweat on the skin surface, with losses of 2 L even observed in lower ambient temperatures [64]. As a consequence of this level of fluid loss, a player will become dehydrated. For example, a 75 kg player with sweat losses of >2 L will become dehydrated by >2%. Individual sweat rates can range from 1.1 L to 3.1 L per 90 min [65], outlining the importance of player awareness of their own sweat rate and to rehydrate accordingly post-exercise.

Immediately post-exercise is a period where rehydration strategies should be implemented in order to replace the volume and composition of important fluids lost through sweat. Without adequate rehydration, negative effects on glycogen restoration and protein synthesis rates [66], sprint capacity [67], and subsequent dribbling performance [68] could prevail. It has been reported that at least 150% of the fluid lost during exercise should be consumed to account for a negative fluid balance and urine fluid losses [69]. In practical terms, for every 1 kg of weight lost during exercise would equate to 1.5 L of fluid required post training and this can be monitored through pre-post weighing by support staff.

Time taken to rehydrate is shorter than repletion of muscle glycogen stores (up to 6 h compared to 48–72 h) as long as sufficient fluid and electrolytes are consumed. Although, rehydration may take less time than glycogen re-synthesis, it should be noted that during periods of fixture congestion, especially where teams are playing back to back away fixtures where significant travel is required, it is important to educate players how best to re-hydrate during travel. Moreover, it is not unusual for teams to train 24 h after a match as well as 24 h before a match, placing even greater emphasis on rehydration. Moreover, players should be encouraged to take on adequate fluids during half-time (i.e. 200–300 mL) and throughout the match when opportunities such as a break in play are apparent, to maintain hydration. This is especially important during hot and humid weather conditions.

Sodium is a key electrolyte that should be replaced for optimum fluid restoration. There is a variation amongst players in terms of sodium lost during a game with a reported loss of 10 g of sodium chloride observed during a 90 min soccer session [70]. The consumption of a high sodium drink containing 61 mmol of sodium in volumes equivalent to 150–200% of sweat loss was sufficient to establish a state of hyperhydration 6 h after ingestion [71]. The optimal sodium level during rehydration could be as high as 50–80 mmol·L⁻¹ which exceeds the amounts found in a typical sports drink [72]. Water is an electrolyte free drink and is not ideal for rehydration post-exercise as a rapid reduction in plasma sodium concentration could ensure which subsequently increases urine output [73]. Therefore, drinks for rehydration should have high electrolyte content (i.e. 40 or 50 mmol·L⁻¹ of sodium chloride) and consist of carbohydrate sources to increase palatability [74] and help with glycogen restoration. In this respect, sports drinks are superior to water for fluid restoration due to their provision of both carbohydrate and electrolytes.

Team sports such as soccer can be associated with a moderate to high post-match alcohol intake to celebrate or commiserate over the game result; especially in the amateur game. Although this practice is slowly diminishing at the elite level, alcohol consumption can negatively affect a player’s ability to recover especially when consumed during periods of fixture congestion [75]. More specifically, alcohol has recently been shown to reduce myofibrillar protein synthesis rates even if coingested with protein, resulting in an impairment of recovery and adaptation from exercise by suppressing skeletal muscle anabolic responses [75]. Moreover, alcohol consumed after a match can also exacerbate dehydration especially when consumed during the recovery period several hours after a match [76]. Thus it is prudent to educate players regarding the negative effects of alcohol on recovery when multiple matches are played within a short period of time.

Recovery nutrition towards the end of a day during periods of fixture congestion as well as intensive training is often overlooked by athletes. For instance, protein ingested before sleep has proven to be effectively digested and absorbed, leading to an increase in protein synthesis and improving whole-body protein balance during overnight recovery [49]. Ingesting a pre-sleep protein snack high in casein such as 200 g of cottage cheese or alternatively, a formulated protein supplement containing 40 g of casein protein will likely prove beneficial for increasing the time in a net-positive anabolic state over the course of a day [77]. This is due to its slow release properties over a prolonged sleeping period. The absence of this pre-sleep feed will not improve overnight protein balance; possibly compromising muscle protein synthesis rates over the 24 h period. A summary of the recovery nutrition guidelines have been summarised in Table 3.

Carbohydrate and protein supplements can be both useful and practical for players to enhance recovery during periods of fixture congestion. We have previously discussed both the importance and practical application of carbohydrate and protein supplements under the “recovery nutrition strategies” section.

During repeated soccer-specific actions phosphocreatine stores diminish significantly as a consequence of adenosine triphosphate regeneration through phosphocreatine hydrolysis in the initial seconds of supra-maximal activity [80]. To increase resting muscle phosphocreatine stores quickly, a creatine loading protocol can be used with the conventional strategy involving 4 × 5 g doses of creatine supplementation per day for 5–7 days proceeded by a maintenance dose of 3–5 g per day [81]. However, a lower daily dose of ~3 g per day for 28 days will result in a similar increase in phosphocreatine stores [81] to the loading protocol. It has been reported that muscle glycogen resynthesis can be enhanced following creatine loading [82]. Practically, creatine can be added to the post-match and post-training recovery drink and it may prove beneficial in optimising refuelling strategies especially during congested fixture schedules.

In agreement with data from the general population [83], empirical observations highlight that sleep deprivation is common on the night(s) prior to sporting competition; especially, if matches require prior international air travel. Interestingly, players who self-reported 7–9 h sleep on the night before testing outperformed their sleep-deprived counterparts (i.e., those reporting 3–5 h sleep) by ~20% in a rugby passing task [84]. Such differences were ameliorated when creatine (50 or 100 mg·kg⁻¹) or caffeine (1 or 5 mg·kg⁻¹) was provided to sleep-deprived players 90 min before skill testing commenced; a response attributed to the attenuation of sleep-deprivation induced reductions in brain phosphocreatine concentrations and the stimulatory effects of adenosine-receptors, respectively [84].

There is some evidence that large amounts of caffeine taken with carbohydrate can enhance glycogen resynthesis post-exercise [85, 86]. Pederson and colleagues [85] found that co-ingestion of carbohydrate and caffeine (4 g·kg⁻¹ and 8 mg·kg⁻¹, respectively) resulted in greater glycogen resynthesis compared to 4 g·kg⁻¹ of body mass of carbohydrate only. Muscle biopsy data showed that although no differences were observed in glycogen resynthesis after 1 h post-exercise (133–37.8 vs. 149–48 mmol·kg⁻¹ dry weight; for carbohydrate and caffeine, respectively), after 4 h of recovery the caffeine condition resulted in a 66% higher glycogen accumulation (313–69 vs. 234–50 mmol/kg dry weight; p < 0.001). Similarly, Taylor et al. [86] found that co-ingestion of carbohydrate and caffeine (1.2 g·kg⁻¹ and 8 mg·kg⁻¹, respectively) resulted in an increased time to exhaustion on the Loughborough Intermittent Shuttle Test compared with the carbohydrate only and water condition. Although Taylor et al. [86] did not take any muscle biopsy data to measure glycogen resynthesis, the authors concluded that adding 8 mg·kg⁻¹ of caffeine to a post-exercise carbohydrate drink improved subsequent high-intensity interval-running capacity, a finding that may be related to higher rates of post-exercise muscle glycogen resynthesis. Whilst the findings of Pedersen et al. [85] and Taylor et al. [86] may be useful for recovery, as they suggest that adding large doses of caffeine to carbohydrate post-exercise can enhance glycogen resynthesis, this strategy may not always be practical, particularly when matches kick off either late afternoon or evening as this strategy will compromise sleep. Nonetheless, this strategy could be employed for matches that have early kick off times.

When time is limited between games, dietary components that modulate the inflammatory process may prove beneficial in the acute recovery phase. However, it is important to note that any form of antioxidant or anti-inflammatory supplement should be carefully dosed. Soccer-specific adaptations are triggered by the inflammatory and redox reactions occurring after a strenuous exercise stimulus. Therefore, chronically high doses in their provision are likely to be detrimental to the long term training effect [87]. For example, large doses of vitamins C and E have proven to have detrimental effects to cellular adaptation [88, 89]. Strategic use of anti-inflammatory and antioxidant foods/supplements in and around periods of heavy training/game scheduling is the best approach for optimal recovery, rather than chronic daily use.

Antioxidant- and polyphenol-rich foods such as cherry and pomegranate juice have been found to enhance recovery following heavy training [90‐94]. For example, 0.682 L a day of tart cherry juice consumption before and after eccentric exercise significantly reduced symptoms of muscle damage [95]. Similarly, Montmorency cherry juice has also been shown to enhance recovery following prolonged, repeat sprint activity in semi-professional male soccer players [91]. In addition, 500 mL of pomegranate juice has been shown to reduce DOMS after strenuous exercise [92, 94]. However, these findings should be interpreted with some caution as participants were fasted and restricted polyphenol based foods beforehand. Theaflavin-enriched black tea extract supplementation in doses of 1760 mg daily for nine days has also been found to enhance recovery, reduce oxidative stress reduce muscle soreness in response to acute anaerobic intervals [96]. Thus, the potential beneficial effects of antioxidants and polyphenols to accelerate recovery are encouraging but more research is warranted using protocols which demonstrate greater ecological validity, especially in relation to soccer specific activity. Nevertheless, in situations where players have back-to-back matches with little time for recovery or in tournament situations where adaptation to training is likely not a key priority, certain antioxidant supplements and polyphenol-rich foods may be beneficial for recovery but chronic use should be avoided.

Omega-3 is found naturally in oily fish such as salmon, mackerel and sardines, and in a more concentration form as a fish oil supplement. Fish oil supplements contain the long chain polyunsaturated omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). It should be noted that the research on Omega-3 fatty acid supplements is conflicting as some studies show beneficial effects on reducing inflammation [97] and delayed onset muscle soreness [98‐100], whereas, other show no benefit [101, 102]. Phillips and colleagues [97] found that fish oil supplementation reduced exercise-induced inflammation. Similarly, other studies have found that 1.8 g [98], 2.7 g [100], and 3 g [99] of Omega-3 fatty acid supplementation reduced DOMS after exercise. In contrast, other studies have found a reduction in oxidative stress following exercise with fish oil supplementation but no difference in DOMS [102] and further studies have no effect on DOMS [101]. Despite the inconsistencies regarding fish oil supplementation, there does seem to be some evidence for using Omega-3 fatty acid supplementation in doses of 1.8 to 3 g per day to reduce inflammation and muscle soreness after matches, especially during periods of fixture congestion.