Lactic Acid

Lactic acid is something that everyone talks about but no one knows really what it is. Lactic acid isn’t what makes you stiff and it doesn’t occur when your muscles are being pushed a bit. Whenever you do wake up the next day with aching muscles, it isn’t because of this acid; it is because of microscopic tears in the muscle fibres that have occurred through a physically demanding exercise. Lactic acid is produced in the mitochondria (where energy is metabolised) when the cells respire anaerobically (without oxygen). This produces a by-product (not a waste product) of lactic acid.

When lactic acid is produced it breaks down into the lactate ion and the hydrogen ion. The lactate ion is very important in the metabolism of glucose and glycogen, but the hydrogen ion is what causes the burn.

The hydrogen ion causes the burn in the muscles and the blood to become acidic. The hydrogen ion also plays havoc with nerve receptors, causing the fibres to contract and cramp up.

So lactic acid has got itself a bad name as being bad for you. On one hand it helps your body release energy, and even provides another energy source for slow-twitch muscles which are used in endurance events.

On the other hand when its “alter ego” the hydrogen ion occurs, it causes spasms, cramps, fatigue and a breathlessness feeling when sprinting anaerobically. Just remember the next time someone says “my legs are burning from lactic acid”, you know they have no idea what they are taking about.