Alcohol & AtHletic Performance Part 1

As enjoyable as the Festive Period can be, I feel it can bring its difficulties. Surrounded by temptation, numerous nights out and lack of routine, it easy to fall victim to the month of December! RIP Christmas! Here we are with the new year well and truly under way, and along with that, a spanking new decade to make the most of! (Happy New Year to all!). As always, it was quite difficult to avoid the murmurs of the new years resolutions of friends , family, team mates and colleagues who are eager to change everything for the better come January the 1st. Understood, the slate is wiped clean and with it comes increased levels of hunger and drive. As we know, this 'motivation' can be easily let diminish if a plan is not put firmly in place. For more on this check out blog post number 1.The following article is part 1 of a 2 part series. The focus today is to briefly overview the physiological implications and effects that alcohol has on our systems and shed some light on the effects it may have on an athlete.

Overview
Alcohol is prominent in global sport. Whether that means friends enjoying drinks, teams celebrating a victory, or the sponsorship deals beverage companies offer sporting organisations, everywhere we look it can be found! Research has shown that traditional field sports such as rugby, cricket, hurling and GAA are found to have the highest percentage of athletes who consume alcohol compared with individual sports such as horse racing and tennis. Alcohol effects various systems of the body such as metabolic, cardiovascular and neuromuscular systems resulting negatively on exercise and performance.

Nutrition
Containing quite a large amount of energy (7kcal/g) it is far from effective as when drinking, the body uses alcohol as a fuel source prior to using anything else so when meals are consumed with alcohol in the system they could end up as excess calories which can lead to fat gain.

Metabolism of Alcohol 
Upon consuming an alcoholic beverage, up to 25% of the alcohol is absorbed straight into the bloodstream from the stomach. The remainder is absorbed by the small bowel. How quickly this occurs depends if your stomach is full, the concentration of alcohol in the drink and if your drink is carbonated. Carbonated drinks are absorbed into the blood stream at a quicker rate, as pressure is increased in the stomach. This helps force alcohol into the bloodstream via the stomach lining. When alcohol is consumed and enters your bloodstream it remains in your body until it is processed.
A large proportion (up to 98%) of alcohol that you drink can be metabolised in your liver. The remaining % is excreted through urine, exhaled or sweated out. The average person will take up to an hour to process one standard drink (8g/10ml). The result of drinking more alcohol than your body can cope with is an increased blood alcohol level.

​Skeletal Muscle
For muscles to contract, calcium is required. If calcium is not present, actin and myosin (Muslce Fibres) are unable to interact (Szent-Györgyi, 1975.) Alcohol inhibits the movement of calcium ions into the muscle cell, which decreases strength. It is also well known that alcohol consumption can result in muscle cramps, pain and loss of proprioception (awareness of body in space), however the mechanism of how this occurs remains unclear.

Nervous System
Different areas of the brain are affected by alcohol. Alcohol decreases central nervous system (CNS) excitability and cerebral activity.  Alcohol impairs balance, reaction time, recognition and accuracy of motor skills. Also, variations in neurological activity has been connected to low sleep quality. Sleep depth is affected with less time of rapid eye movement sleep (REM) (Vella and Cameron-Smith, 2010). The more alcohol consumed prior to sleeping, the more REM is impacted however it is delayed regardless of the levels consumed. The hippocampus is an area in the brain that is affected by lack of deep sleep. It works to transfer recently learned information to the neo-cortex to utilise at a later stage. This learned information includes muscle movements and visual information, vital for sports performance.

Endocrine System
Muscle growth and repair can be affected if alcohol is consumed regularly. The production of testosterone is altered, while estrogen production is elevated. Although dopamine is released through consumption of alcohol which can make us feel good, the hormones that regulate our emotions are actually being disrupted. A decrease in alertness can be the result of long term alcohol abuse as this increases levels of GABA (an inhibitory neurotransmitter). Lastly Alcohol limits the production of the ‘happy hormone’ serotonin which can lead to depression.

Cardiovascular System
It has been found that alcohol consumption can also cause disturbances to cardiovascular function that include increased heart rate, decreased left ventricle performance and increased blood pressure.
Part 2 of this series on how alcohol affects athletic performance, will focus on the effects it has on recovery and injury. Thank you for reading !