What is the difference between Isotonic, Hypertonic and Hypotonic drinks?

The terms isotonic, hypertonic, and hypotonic refer to the osmolality of a solution, especially in the context of sports drinks or bodily fluids. Here's a quick distinction between them:

Isotonic

An isotonic solution has the same osmolality as the body's fluids. This means it has the same concentration of solutes (like salts and sugars) as what's found in the body. Isotonic drinks are often used during exercise because they provide a balance of hydration and energy and reduce the likelihood of gastrointestinal issues.

Hypertonic 

A hypertonic solution has a higher osmolality than the body's fluids. It contains a higher concentration of solutes. Consuming a hypertonic drink might draw water out of the body's cells into the intestines, which can lead to dehydration. Hypertonic drinks might be used after exercise to quickly replenish glycogen stores but should be consumed with caution during exercise.

Hypotonic 

A hypotonic solution has a lower osmolality than the body's fluids, that is, a lower concentration of solutes. Drinking a hypotonic solution may cause water to move into the body's cells or bloodstream. Consuming too much of a hypotonic fluid can lead to over hydration and water retention. Some signs include puffy fingers you're exercising. The biggest risk however, is increased fluid retention in your brain, which can have serious consequences. 

Hypotonic drinks are often used when rapid hydration is needed without the extra energy from sugars.

In summary, the choice between isotonic, hypertonic, and hypotonic solutions depends on the specific needs of hydration and energy replenishment during or after exercise. Isotonic is generally balanced, hypertonic is more concentrated, and hypotonic is less concentrated.