Sports Nutrition: Drinks and Supplements....

Hydration

Water accounts for 45-70% of your total body mass and adequate hydration is vital to your performance, recovery and indeed your general health!

Whatever level of competition you compete at, and whatever your sport, you still need to be well-hydrated before, during and after exercise. Dehydration affects your mental as well as physical performance. Your brain is approximately 85% water and even mild dehydration will affect your concentration, alertness and motivation.

So how do you know if you’re dehydrated? Everyone associates thirst with the need to drink more water, but thirst is a poor indicator of your hydration levels. If you wait until you're thirsty to drink and then stop drinking as soon as your thirst is satisfied, you’ll still be between 25% and 50% dehydrated.

"Roughly speaking you will lose about 1 litre of fluid per hour while exercising"

Urine colour is a more reliable indicator of hydration status and generally speaking, the lighter the urine colour, the more hydrated you are.

Guidelines for the daily intake of fluid for an adult female are 2.7 litres and 3.7 litres for a male. Roughly speaking though, you need to take on 1ml of fluid for each calorie you take in. Therefore, if you’re eating 2500 kcal a day, you need to be taking on 2500ml (2.5 litres) a day, about 0.7 litres of which will come from the food you eat.

Even with little or no exercise, your body loses approximately 2.5 litres of water every day from your urine (1250ml), your skin (850ml), your lungs (350ml) and your faeces (100ml). During intense exercise in hot weather this value will rocket. You can lose up to 5 litres from sweat alone. The fitter you are the more you sweat! Roughly speaking you will lose about 1 litre of fluid per hour while exercising, athletes may lose up to 3 litres per hour!

It is possible to take on too much water with very serious health consequences. Your body fluid contains dissolved salts called electrolytes (sodium, potassium, calcium, magnesium, chloride, bicarbonate). Electrolytes help regulate your blood pH and are critical for nerve and muscle function.

If you drink too much water you can actually dilute the concentration of sodium in your blood. This causes extra water to enter your cells and they swell. If your brain cells swell they cease to function, which can lead to coma and death. This is called hyponatremia. Early symptoms of hyponatremia include muscle weakness, incoordination and disorientation. Although hyponatremia is extremely rare, it can and does happen which is why sports drinks, which help replenish your electrolyte levels as well as your fluid levels, are preferable to water alone during endurance events.

Sport Supplements

Sports supplements will not compensate for a poor diet, but if you’ve already sorted your diet, they’re worth looking into as they will certainly give you that little extra. There are many types and the one most suitable to you will depend on many factors, not least of which is your particular sport.

Sports supplements are classified A, B, C, D, based on the scientific evidence supporting their use and whether the product is deemed safe, effective and legal. Class A supplements are backed by the greatest scientific evidence, Class D supplements on the other hand are banned substances. I’m going to concentrate on the Class A supplements, but that is not to say that Class B supplements cannot help you, just that the evidence supporting their use is not as compelling.

"A regular black coffee, an hour before exercise, is all you need to improve your performance"

One class A supplement is caffeine which, due to its effect on your central nervous system, can boost your energy levels, alleviate fatigue and increase your concentration and focus whatever your sport.

The recommended daily limit is only 400mg per day for adults, 200mg per day during pregnancy. Personally, I probably exceed this before breakfast, but at my age I take a lot of getting going!

A regular 225ml coffee contains about 100 mg of caffeine. Many energy drinks such as ‘Monster’ contain huge levels of caffeine but for many reasons they are not a healthy source and not one that I would recommend. It’s easy to exceed the recommended dose and this can have several negative effects including; insomnia, irritability, stomach upset, fast heartbeat and muscle tremors.

A regular black coffee, an hour before exercise, is all you need to improve your performance.

"The International Institute of Sports Nutrition describe creatine as

‘the most effective nutritional supplement to increase high intensity exercise capacity and muscle mass"

Creatine, another Class A supplement, is a protein made naturally in your body and also obtained from the meat and fish you eat. Creatine fuels your body during high intensity activity making it suitable if you are a sprinter, weight lifter or play a team sport.

The International Institute of Sports Nutrition describe creatine as ‘the most effective nutritional supplement to increase high intensity exercise capacity and muscle mass’.

Guidelines for taking creatine monohydrate are: Loading phase (4 x 5g doses per day for 5 days), followed by the maintenance phase (1 x 5g dose per day for 12 weeks), followed by a 4-week break.

Beta-alanine is a naturally occurring amino acid, and also a class A supplement, that produces carnasine. Carnasine reduces your muscle acidity during exercise allowing more lactic acid to be produced before you start to fatigue.

Like creatine, beta-alanine is more beneficial if you participate in high intensity sport rather than an endurance sport. The only reported side effect of taking beta-alanine is that you may feel harmless paraesthesia (pins and needles) which usually goes away within 1 week of supplementing.

Guidelines recommend taking 4g-6g daily for 6-10 weeks.

Beetroot juice has recently been promoted from a Class B to a Class A supplement. Beetroot itself increases the amount of nitrate in your blood which leads to an increase in nitrous oxide. Nitrous oxide, is a vasodilator that widens your blood vessels allowing more oxygen and nutrients to reach your muscles. The more oxygen and nutrients you can get to your muscles, the harder and longer you can exercise before fatigue sets in.

Beetroot juice could be of real benefit if you are an endurance athlete and has no known side effects other than it may turn your urine and stools pink!

A typical dose of beetroot, would be 500ml of juice, or, 140ml of concentrated juice, or, 200g of cooked beetroot, taken daily for a week or alternatively, taken 1-2 hours before exercise. Personally, I wouldn’t recommend taking the full dose just before exercise until you’re confident you can stomach it!

Protein, another Class A supplement, is available in powder, liquid or bars. The two most popular types are whey and casein.

Whey is readily available, cheap, and ideal for muscle building. It is quickly digested and absorbed making it an ideal post-workout supplement.

Casein is digested slightly slower than whey which results in a steady release of amino acids over several hours making it a very good general use protein and ideal for use before you go to bed. Casein is also particularly useful if you suffer from delayed onset muscle soreness.

"Bicarbonate buffers lactic acid during anaerobic exercise allowing you to maintain force and power for longer"

Sodium Bicarbonate (Baking Powder) is naturally occurring in the body. When you exercise, the pH in your body naturally lowers leading to the production of lactic acid and the onset of fatigue. During anaerobic exercise, bicarbonate buffers the lactic acid allowing you to maintain force and power for longer. There is good evidence that bicarbonate will help with repeated sprints, team sports and power sports.

Sodium bicarbonate may be unpalatable so you should always take it with plenty of water. It may also cause you some gastrointestinal (GI) distress until you get used to it, so build up gradually to the recommended dosage.

Protocol for taking bicarbonate is; 0.3g per Kg of bodyweight taken 1-2 hours before exercise.

Fish oil is only a group B supplement but has been shown to; reduce muscle soreness, improve delivery of oxygen and nutrients to muscles, reduce inflammation and increases muscle synthesis.

Fish oils are great for endurance sports but also great for your general health. You should aim for predominantly omega-3 fatty acids from sources such as wild salmon.

Logically, for every person who exercises because they participate in sport, there will be another person who exercises in an attempt to gain weight (#gym #muscles) and another person who exercises to lose weight (#holidays #beach ). For that reason I have decided to do one more short blog, to round of the series, looking at nutrition's role in weight loss and weight gain, which will be coming up shortly :-)