Title: Nutrition and Professional Football

Key words: optimal nutrition, training, fitness, diet, nutrition, metabolic acidosis, hydration level, circadian rhythm, jet lag, hypoglycaemia, glycogen depletion, dehydration, vitamins, minerals, antioxidants, essential fatty acids, hyperhydration, creatine, glutamine

Date: Aug 2000

Category: 12. Sports

Type: Article

Author: Dr van Rhijn

 

 

Nutrition and Professional Football

 

Introduction

Football is a very demanding sport, played during long seasons in rapidly variable climates and time zones, where gruelling training and match schedules allow little recovery time between performances. Optimal nutritional support is central to maintain performance, fitness & body composition, prevent fatigue & injury and aid recovery & health for professional squads1. This paper addresses the scientific evidence for nutritional strategies.

 

General Causes of Fatigue

Fatigue affects performance adversely and is dependent upon the individuals’ status on training, fitness, diet, nutrition, metabolic acidosis, hydration level, circadian rhythm, jet lag and external environmental factors such as temperature, altitude and humidity. Other health issues may undermine fitness and contribute to fatigue such as gut dysbiosis, food intolerance, allergies, low-grade infections, mood states and homesickness. Match fatigue is mainly due to hypoglycaemia, glycogen depletion2 and dehydration.

 

Optimal Nutritional Requirements and General Strategies

Practical nutritional interventions are required to establish healthy habits that meet all the nutrient requirements to minimise fatigue, maintain hydration, promote recovery, growth and development3. Players must be thoroughly assessed4, including their dietary5 and fluid intakes and monitored throughout the season. Strategies are adapted according to events i.e. training, match play, rest, recovery, injury, season and different requirements whilst travelling. Encourage wide variety, highly nutritional value foods (fruit / vegetables / fatty fish) to provide vitamins, minerals, antioxidants and essential fatty acids. The verdict regarding ergogenic aids is still out for most supplements, but players risk low intakes of Zn, Mg, Ca6 and B-group vitamins7 to warrant supplementation with antioxidants8, despite compensatory biochemical adaptation to severe exercise9.

 

Energy

Football is a high intensity, intermittent activity requiring short-term, repeated, explosive bursts of maximum effort with short recovery periods in between. Many players struggle to keep their weight between matches despite a recommended daily energy intake of 14-15 MJ/day, generally obtained from CHO (8-10g/kg/day [60-65%])10, Protein (1.4-1.7g/kg/d [12-15%])11 and Fat (1.7-2.5g/kg/day [20-30%])12,13. CHO conversion into muscle glycogen is essential to provide strength, endurance, intensity14, speed, saturated stores and to delay lactate build-up and fatigue, thereby enhancing recovery15.

 

Fluids

Fluid losses from sweating can be enormous16 and depend on environmental temperature (1.5L [10-150C] to 3.5-4L [30-380C])17. Dehydration impairs performance18 by reducing thermal dissipation19, muscular endurance & strength and causes muscular cramps, exhaustion, heat stroke, coma and death if extreme. Minimum requirements are 2-2.5 L/day and hydration can be monitored by weighing and urine analysis.

 

Ergogenic Aids

Creatine, a nitrogen compound synthesised from amino acids and stored in skeletal muscle (95%) as phosphocreatine (PCr)20, benefits competitors participating in sports requiring short-term21, repeated22, explosive bursts of maximum effort. It enhances peak performance23,24, endurance capacity25, total work output26 and delays or prevents fatigue27 by providing APT for the immediate ATP-CP phosphagen energy system28. Glutamine, a conditionally essential amino acid is reduced in muscle stores during strenuous sport activity29. It is essential in improving immunity30,31,32, maintaining gut integrity33 and regulating protein turnover34 (nitrogen donor).

 

Nutritional Strategies During Match Play

More emphasis is placed on CHO and hydration than protein and fat fish meals during matches to enhance performance. Low bulk, high complex CHO (12-13g/kg/day) is required, divided in pre-match (1-4 hours) loading (fill glycogen stores35), and post match refuelling36. Significant performance ergogenic benefit is obtained from CHO beverages during prolonged exercise37,38, especially in glycogen compromised individuals39. Hyperhydration (personal water bottles), ideally in the form of isotonic sport drinks40, should be encouraged (500ml pre-match and 500-800ml at ½ time) to replenish losses and also enhance performance41 and endurance42. Post-match rehydration is essential43, but avoid hypertonic solutions, which delay gastric emptying44 and promote dehydration45,46.

 

Conclusion

Proper, professional nutritional support, tailored to the individual, is essential to ensure peak fitness and health during the demanding season. There is too much at stake to be negligent about the increasing science behind nourishment.

 

 

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