jeudi 23 avril 2015
Hydration and sports drinks
Hydration and sports drinks
If
you exercise hard enough you will start to sweat, which is your body’s
way of cooling itself, and it is not unusual to lose a litre of fluid
during an hour of intense exercise. Your capacity to exercise, or even
function, reduces as you lose fluid, and losing just 2% of your
bodyweight can impair your function by as much as 15%. To maintain your
hydration levels you need to replace the fluid lost through sweating. As
well as losing fluid when you exercise, you are using up vital energy
stores so you might also want to top-up your carbohydrate levels.
Consuming carbohydrates at the same time as water can slow down the
rate at which your drink empties from your stomach and becomes available
for absorption through your small intestine - so you need to get the
concentration of carbohydrate (sugar) right. If your main aim is to
replace lost fluids then an isotonic drink is the most appropriate. An
isotonic drink contains 4-8% sugar and is absorbed at about the same
rate as plain water, with the advantage of an energy boost.
There are plenty of commercially produced sports drinks available but
they are not essential and do not give you any advantage. A good guide
for making your own sports drink is fruit juice with water in the ratio
of 1:1, or squash with water in the ratio of 1:4, e.g. 200 ml squash and
800 ml water. Be sure to use squash made with sugar rather than
sugar-free.
It is generally not necessary to add electrolytes to your sports
drink as your body has its own efficient mechanisms for regulating
electrolyte balance and will cope with normal sweat losses. The only
electrolyte that may be of benefit is sodium to enhance absorption of
your drink. You only need a small amount of sodium each day though for
your body to function efficiently and you can get adequate intake from
dietary sources. If you want sodium in your sports drink then add 1-1.5
g of salt per litre of liquid, not so much as you taste it so try just a
little first.
The amount of fluid you need to drink during and after exercise
depends on how much you sweat, and everyone is different. As a rough
guide you are likely to need one litre of fluid for every hour of
exercise. To find your individual requirement, weigh yourself before and
after your exercise session (near naked is best) and the difference is
the amount of fluid you have lost. One kilogram of bodyweight lost
equals one litre of fluid. For every litre of fluid you have lost
(sweated) aim to replace it with one and a half litres of fluid. This
ensures your body has sufficient water for all its metabolic functions.
As well as rehydrating during and after exercise, ensure you are
properly hydrated before you begin your session. As a guide, drinking
half a litre of water two hours before your exercise session and a
further half a litre 15 minutes before you start will ensure you are
well hydrated.

http://www.nutritionist-resource.org.uk/nutritionist-articles/hydration-and-sports-drinks
About: Unknown
You may also like...
Inscription à :
Publier les commentaires (Atom)
Popular Posts
-
Supplements are used by athletes, bodybuilders and sports men and women to boost their strength, performance and recovery, and are...
Aucun commentaire:
Enregistrer un commentaire