When we run we stress our bodies. While a bit of controlled stress is good for our development, one of the surest ways to stress just about every part of our bodies in a negative way is to run in a poorly hydrated condition.
We are made of up to 60% water. Our brains and heart are composed of 73% water, our lungs are about 83% water. The skin contains 64% water, muscles and kidneys are 79%, and even the bones are watery: 31%. Water is the most abundant chemical in our physical make up and the body has complex methods of keeping the balance correct, but that is reliant on adequate supplies of water being taken on board in the first place.
Good hydration means our bodies can optimise the function of just about every cell in the body. It permits the brain to generate hormones and neurotransmitters. It converts food in our digestive tracts and flushes body waste. It helps deliver oxygen to all parts of our body and regulates blood volume and pressure. It helps lubricate and provide cushioning in our joints. It regulates our body temperature by allowing us to sweat.
As runners, dehydration has the effect of thickening our blood, impeding the transport of oxygen to our muscles, leading to the often mentioned heavy legs and tired muscles. The heart works harder and blood pressure and body temperature are raised. Poorly lubricated joints are harder to work. Cartilage loses its cushioning efficiency and becomes more prone to damage. Headaches, stitch, muscle cramps and general lethargy can also be caused by dehydration.
None of the above is going to help you enjoy your running, nor perform to your potential. So what do you need to do to be fully hydrated? If you search the internet, as I have done on your behalf, you will find variation in the recommended amounts for daily intake of fluids but usgs.gov/special-topic/wate... suggests that an adult female needs to intake 2.2 litres of fluids daily, while the recommendation for an adult male is 3 litres per day. This includes fluids that we ingest as part of the food we eat. These recommendations are middle ground and as runners, partaking of strenuous physical exercise, we need to take these as minimums.
Water, pure and simple, is the best form of hydration as it can be utilised immediately by the body, with no side effects from sugars, tannins or caffeine that may be in other drinks. Many teas, coffee and alcohol are diuretics, which means they will increase your excretion of fluids, which basically means that half a pint of coffee, for instance, will not hydrate you as well as half a pint of water. It will help, but not as efficiently as pure water and the caffeine will likely raise your heart rate.
This article runnersworld.com/uk/nutriti... suggests that you need to drink 500ml two hours before your run to be fully hydrated, with a top up of 150 ml immediately before you head off. If you are a morning runner like me, that is impossible to do, so it is best tackled by making sure that your hydration during the previous evening is adequate and taking on board some fluids before the run. I drink 500ml immediately before setting out on a run. By drinking small amounts throughout the day you keep your hydration in balance, hence the recommendation to hydrate well each and every day, running or not, will avoid peaks and troughs.
For C25k workouts which last a maximum of 40 minutes, if you have hydrated effectively beforehand, then there is no need to carry water with you on a run, unless you want to pour it on your head to keep you cool. I have never carried water for any run under an hour’s duration and believe that for most people it is unnecessary, unless it is extremely hot or you have specific medical conditions. If doing runs of longer than an hour then it is important to keep fluid levels up and generally start to sip occasional mouthfuls after the first 5k or so, then top up regularly.
A common theme on the forum is people complaining of neck and shoulder tensions. This invariably is caused by carrying phones or water bottles in hands, causing asymmetry and tension, which is best avoided. There are many bottle carrying belts available in which to carry water. I bought one that holds a single 750 ml bottle, which is a bit bulky and creates more of those asymmetries, which do not contribute to efficient running, so I would think that those that hold two smaller bottles may be more balanced. The other option is a Camelback or backpack containing a bladder, which can hold up to 2.5 litres of water, but are only really appropriate for ultra distance runs.
After your run it is crucial to replace lost fluids within a short time of finishing. Try to drink 500ml within half an hour and continue to top up regularly. If you want to know how much fluid you lose during a run, weigh yourself naked, immediately before and after your run (I recommend that you get dressed in between).The difference in weights will be almost wholly down to the amount of fluids lost through sweating during your workout.
The response from some to the suggestion that they should drink the recommended amounts of fluid is that their bladders are not up to it. There is no denying that if you drink more you will pee more frequently, but your body will be in better shape. Having listened to Woman's Hour on Radio 4 for the past thirty years, I am very well aware that there are exercises and help available for those with bladder control issues, which are the answer rather than reducing intake of the vital fluid that our bodies are totally reliant upon. Those who follow the above advice, having previously run in a state of inadequate hydration, invariably realise what a positive difference it makes. If you want to run, you need to drink.
If you follow the Runner’s World link above, you will find mention of hyponatraemia, a potentially serious condition that creates a sodium deficiency, caused by drinking too much water in a short time span. If you stick to the advice given above, then you will not be at any risk of this occurring.
Some drink when they feel thirsty, however this is not a good approach for runners. When you feel thirsty you are already dehydrated………..so your body is already functioning below par.
One of the simplest ways to check that your hydration is about right is the colour of your urine. Ideally it should be a very pale straw colour. If it is becoming a stronger yellow then you need to top up your fluids.
If none of the above explanations of how your amazing body functions convinces you of the need to hydrate effectively, then let me appeal to your vanity………….good hydration vastly improves your complexion, after all, your skin is 64% water.
There are more FAQ posts giving general information here healthunlocked.com/couchto5...
Hydration 
