Caffeine as an Ergogenic Aid for Sports Performance and Weight Loss

Caffeine is the most commonly used drug in the world with about 90% of people worldwide consuming it in regular everyday items such as tea, coffee, chocolate, energy drinks, and other foods. The effect of caffeine for reducing fatigue and increasing alertness has been recognised for centuries. In fact, it was only removed from the WADA (World Anti Doping Agency) banned substance list in 2004, and is currently on the monitored substance list. Although widely considered to provide energy enhancing benefits, caffeine provides no nutritional value, and its effects are mediated through its stimulant effect on the central nervous system (CNS) which are similar to, yet weaker than, those associated with amphetamines.

Performance Benefits

There is evidence supporting the benefits of caffeine across a range of sports, from endurance events lasting several hours like marathon or triathlon, to high intensity intermittent sports such as soccer and rugby, and sustained high intensity events from 1-60 minutes in duration like middle-distance running. 

Caffeine has been shown to produce a small but worthwhile effect on endurance performance. It has been reported to alter the functioning of receptors in the brain that regulate fatigue, influence ratings of perceived exertion (how hard the exercise feels), and lowers pain perception, all of which can improve performance. 

• In endurance events, caffeine has been shown to increase work (power) output and time to exhaustion. Caffeine mobilizes free fatty acids from the bodys adipose (fat) or intramuscular fat stores. This results in a greater use of fat for energy which slows the depletion of glycogen (carbs are broken down to glycogen in the body) and delays fatigue. As with all research on sports nutrition the improvements vary depending on the testing protocol used and benefits ranging from 0.7%-17% have been reported with improvements in the range of 4%-6% most common.
• During high-intensity exercise, the primary benefit of caffeine is evident in enhanced speed, strength and power production. Enhanced neuromuscular functioning has been reported by several researchers, resulting in greater muscular force production and decreased reaction time. 
• Caffeine also has benefits for cognitive tasks, improved short-term memory, motor learning, and an ability to sustain concentration have been reported.

How Much and When?

Research has shown that the beneficial effects of caffeine occurs when caffeine is consumed in anhydrous (tablet) form rather than in coffee or other food sources.  So how much caffeine is too much, and when should you take it?

• Caffeine has been shown to be most effective at relatively low doses with 2-3 mg/kg deemed optimal (e.g a 70kg person should consume 140-210 mg of caffeine for optimal results).There is no further dose-response benefit when consumed at higher doses.
• When taken in tablet form, caffeine reaches peak levels in the bloodstream after 20-75 minutes. It has been shown to improve performance for up to 6 hours after ingestion, and the majority of research recommends ingestion 60 minutes prior to performance for optimal absorption.

Weight Loss

As has been already noted, caffeine helps to increase endurance performance by mobilizing fatty acids which can then be burned as fuel. The best effect for fat metabolism is seen when exercising at low intensities and with relatively low doses of caffeine (2-3 mg/kg). When using caffeine to aid weight loss, it is important not to eat anything beforehand as this will cause the hormone insulin to be released and carbohydrate metabolism will begin. So the best time for fat loss will be in the morning, after an overnight fast, and with caffeine supplementation. But remember, the best way to increase fat oxidation is through regular exercise training, fat burning sessions can have a place in your training schedule but try to mix up your training by incorporating different intensities for the best response.

Adverse Effects

A common misconception is that caffeine induces dehydration during exercise.This is not supported by the literature, and several studies have failed to show any changes in sweat rate or fluid loss as a result of caffeine consumption. Several side effects are associated with caffeine consumption including gastrointestinal discomfort, increased anxiety, insomnia, heart palpitations, and tremors. It is also important to remember that caffeine is a drug and is physically addicting, discontinuation can cause some withdrawal symptoms. Typically, intakes greater than 9 mg/kg increases the risks of side effects.

Conclusion

So to conclude, caffeine has a performance enhancing effect across a broad range of sports independent of the duration. 2-3 mg/kg consumed in tablet form is optimal, taken approximately 60 minutes before you exercise.It can aid in weight loss provided it is taken under the right conditions. Finally,in order to limit your chances of side effects, keep your intake levels below 9 mg/kg.

The Effect of Alcohol on Sports Performance and Recovery

Consumption of alcohol has been a time-honoured tradition for celebrating sporting performance. Alcohol is the most commonly consumed drug amongst the athletic population, with traditional field sports players of soccer, rugby, cricket, hurling, and gaelic football  found to have the highest percentage of consumption. Most players are aware of the negative effects of alcohol on performance on the night before an event. Alcohol is a depressant which affects the central nervous system and alters brain function. The results of which includes impairment of many mechanisms necessary for successful athletic performance like reaction time, hand-eye coordination, and balance. What is less understood however is how alcohol affects athletic recovery in both the short and long-term.

The Effect of a Hangover on Sporting Performance

It’s not uncommon for recreational athletes or ‘weekend warriors’ to have a few drinks (or a lot of drink J) on the night before a game. Irish researchers performed fitness assessments on rugby players and then asked the players to consume a regular amount of alcohol for a typical night out, and report for  re-assessment 16 hours later. They found that a hangover inhibited aerobic performance by 11.4% on average. The mechanisms behind the performance impairments are dehydration, acid-base disturbances, and alterations in glucose metabolism via insulin action. Heart function was also affected during the hangover phase and could be seen with an increased heart rate and blood pressure.

Short-Term Effects on Athlete Recovery

·         During a typical match lasting 80-90 minutes it is not uncommon to lose 2-5% of body weight through dehydration and depletion of muscle and liver glycogen (carbohydrates are broken down to glycogen in the body and stored in the liver and muscles to be used as fuel). Adequate rehydration and refuelling is essential after a game in order to speed up recovery for the next game or event, timing is important and a high protein and carbohydrate meal is recommended within 2 hours of the final whistle. Replacing fluid losses is also a priority and a good rule to follow is to replace 1.5 times the amount of fluid lost through sweat, so if you sweat 1 litre, then drink 1.5 litres. Simply weighing yourself before and after exercise will give you a good indication of how much sweat is lost, as 1kg of weight loss equates to about 1 litre of sweat.

·         However, rather than following these guidelines, what commonly occurs is that this important time period is spent drinking and this has a negative effect on recovery. A commonly held misconception is that beer is effective at replacing fluid losses. Beer, and other alcoholic beverages of about 4% alcohol volume have a diuretic effect on the kidneys and promote urine loss resulting in further dehydration. What is recommended is that in the immediate aftermath to consume some water, and then try to stick to some mid strength beers, or spirits served in large glasses with a non-alcoholic mixture before hitting the stronger stuff if you must.

·         Research has shown that those who consume alcohol on a regular basis are more likely to get injured than non-drinkers. Those who drink 1 night a week had an injury rate of 54.8%, whereas the non-drinkers injury rate was 23.5%. Collision injuries are common in team sports resulting in a temporary loss of function. Alcohol can impair optimal recovery, and if full recovery is not achieved then further injury is likely. The underlying mechanisms affected are inhibited immune system function, and inability to limit blood flow to the injury site that can result in an oedema or build up of fluid causing swelling.

Long Term Effects

·         Alcohol is high in calories, providing 7 kcal per gram which is more than carbohydrates and protein (4 kcal per gram) but less than fat (9 kcal per gram). However not all calories are created equal and alcohol is considered and ‘empty calorie’ as it does not provide glucose or nutrient benefits. A common misconception is that the carbohydrates in beer are responsible for the weight gain or beer belly associated with long-term consumption, this is not true, it is the alcohol in beer that is to blame.

·         When available, the body uses alcohol as its preferred fuel source. So when you have your high-fat takeaway at the end of the night, the fat in this food is stored in the stomach, hips, and thigh area as opposed to being used as fuel.

How to Survive a Night Out

So how can you enjoy a night out without severely negatively impacting performance or recovery? Well here’s a few tips on how to enjoy alcohol responsibly.

·         Eating before drinking can speed up the recovery process by providing your muscles with carbohydrate and protein rich foods (chicken, steak, fish, with veg or a sandwich with lean meat are good choices).

·         Try to pace yourself, if you are dehydrated you will drink much faster so aim to start with a non-alcoholic drink first to quench your thirst and replace fluid losses before having a couple of mid-strength drinks.

·         Try to avoid ‘rounds’ as this encourages drinking at a faster pace, also try to keep busy while drinking. Playing pool or darts are better options than sitting and drinking.

·         Always try to have a glass of water before you go to bed, this is a good way to prevent a hangover and get the rehydration process under way.