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As your training miles add up and the countdown continues with 10 weeks to go to the Run The Line event it is worth having a look at hydration and electrolytes and the function they play in the body when we run. This is important information for new runners but also for those seasoned runners among you to jog the memory, no pun intended. Generally you will not need to add electrolytes until you reach the 10k marker, anything over that and you definitely need to give your body a helping hand. An electrolyte imbalance can cause a number of side effects including heart rate fluctuation, blood pressure imbalance and cramp and who wants any of those issues to deal with in the middle of the wilderness? It might be a mountain rescue event but nobody really wants to avail of their services on the day right?!

Let's start with the big one, hydration! It is extremely important to maintain adequate hydration during all exercise. Just a 2% dehydration rate causes a reduction in performance ability and a raise in body temperature and at 5% can cause problems with the digestive system and heat exhaustion. Dehydration also causes blood to thicken putting pressure on organs, especially the heart and reduces the bodies ability to transport nutrients. Generally we need to consume two to three litres of water a day including that in our food. There is a way to calculate your water needs for exercise by weighing yourself before and after the training session to see how much fluid has been lost. Personally I don't consider this an accurate method as any number of factors can give a false positive reading. Environmental changes such as indoor vs outdoor training, intensity of the training session, the amount of carbs you have eaten in the run up to the session, alcohol and caffeine intake and hormonal influences all affect the result from one day to the next. My approach is to ensure you are drinking little and often throughout the day. While you are running you need to be aware of how your body feels. Anticipate water needs before they occur, if you are at the point where you feel really thirsty you are already dehydrated and it will take the body all the longer and all the more energy to get back to a place of balance. Think of your body as a steam train, you don't throw all the coal onto the fire in one go, you have to add little and often to keep

boilers from blowing up and to make sure you reach your destination.

Salt is an electrolyte greatly influenced by hydration levels.

Salt is an electrolyte greatly influenced by hydration levels. Salt works with potassium to maintain blood pressure levels and unless you are on a very restricted diet it is highly unlikely you are lacking salt in your diet. Athletes do however suffer from a condition where there is too little salt concentration in the body called hyponatremia. This can be quite serious but is more likely to occur in beginner competitors or those who are poorly conditioned for an event. The usual suspects for the cause of the condition include drinking too much before the event, taking on more fluid than that which is lost, the use of diuretics, caffeine included, and too little salt in the diet especially during a long distance event. Symptoms are similar to those of being drunk and include disorientation, in-coordination, muscle weakness and black outs. We all need to watch out for each other when we're on the trails and roads so if you notice a fellow runner with these symptoms stop and help as they may not be able to help themselves! How do you prevent hyponatremia? Be aware of salt and fluid intake is the simple answer and always bring an electrolyte drink on your long runs (10k+). You could use a home made electrolyte drink such as a 50:50 mix of water and orange, apple or cherry juice to make a litre of fluid with a good pinch of salt mixed in. If you would rather an “off the shelf” option coconut water is my drink of choice. It has the perfect balance of sugars, sodium, magnesium and potassium all in the one place! There are flavoured options available including watermelon, mango and chocolate (yes, you read that right, chocolate flavour!!) for those of you who aren't keen on a coconut taste. There are also electrolyte sports drinks widely available.

Coconut water, the perfect balance of sugars, sodium, magnesium and potassium all in the one place

This leads me nicely onto magnesium, my favourite electrolyte. Yes, I am a geek! We need magnesium for a whole array of functions throughout the body but what we runners are concerned most about is bone health and muscle relaxation. Bone health is obvious, we need strong bones to support the constant wear and tear they undergo while we're out enjoying the countryside and pounding the pavements. Muscles work in pairs and in opposites, when one contracts, it's opposite relaxes. This action alternates so we can get power from the muscle that contracts but we need it to relax so power can be released and it can contract effectively again. When this doesn't happen we get muscle spasm and cramp. Adequate magnesium in the diet is essential to preventing the legs cramping up on those long runs. Deficiency signs can include fatigue, poor memory, rapid heart beat and muscle twitch and anyone undertaking a heavy training schedule needs more than the average Joe. Be sure to include some food sources of magnesium in the diet rather than relying on sports drinks, the whole food option is always the best choice and will provide other nutrients at the same time. Magnesium is found in coconut water as mentioned above but also in cashew nuts, pumpkin seeds, peanuts, watermelon, beans, cacao powder and nibs, brown rice and bananas. I particularly like cashew nut and cranberry mix or making my own trail mix with a load of cashews, pumpkin seeds and cacao nibs in among the other nuts and dried fruit.

Magnesium is found in amongst other foods watermelon!

As mentioned above, sodium and potassium work together to maintain body fluid balance and regulate blood pressure and for nerve function so our legs move in the direction we want them to go! A potassium deficiency can lead to high blood pressure, fatigue and a decreased heart rate. If you suffer from high blood pressure reducing salt and increasing potassium intake will help to balance things out. As athletes we need potassium for muscle contraction most of all. Potassium is however one of the most abundant minerals in the diet so it is not difficult to get what you need.

Bananas are an excellent source of potassium as well as quick release sugars making them every runners go to snack.

Bananas are an excellent source of potassium as well as quick release sugars making them every runners go to snack. It's nice to mix things up a bit though so why not try an orange, raisins orsome peanuts instead? Potatoes with the skin on, tomatoes, beans, spinach are more great sources to include on the dinner plate with some watermelon for desert, perfecto!

The Author

Julie-ann is a qualified nutritionist based in Co. Wicklow who specialises in sports nutrition for performance and recovery for all levels of fitness. A keen runner herself, she is currently training for Dublin City marathon 2018 so has first hand experience in understanding not just the nutritional demands but also the mental and physical demands of all sports. Nutrition is now being looked to more and more to improve performance, speed up recovery and provide an edge against the competition. As Julie-ann says herself, "everything you eat is fuel for the body but the body needs the best fuel to get the best results. You don't put the wrong fuel into an expensive sports car and you need to think the same way about yourself! You've probably spent a small fortune on running shoes, sports watches and all the other accessories so why risk reducing performance by not giving your body what it needs?"

Over the coming weeks Julie-ann will be providing nutritional information for all competitors via our blog so be sure to check in and have a look.

Check her out on Facebook and Instagram.

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