Backpacks w/side water bottle storage: Water is normally the heaviest item carried in or on a pack.
Bio-mechanically, this is a poor method of carrying water.
You are thrusting the water bottles forward and back w/each step you take.
When you remove the water bottle to drink and consume some of it, the bottle on the other side has more or less of the bottle you are drinking from. Your load carrying is now asymmetrical.
Additionally, you try and return the bottle(s) through the elasticized outer pocket. Most frequently, you have to take the pack off to return it to the pocket.
Bladders are a better solution in that the load is essentially center on your spine and include a hose and bite valve for on the go drinking.
However, bladders suffer from the need to be cleansed hygienically, the water tastes lousy and they weigh substantially more than a typical water bottle.
Regarding electrolyte, I prefer bee pollen. A tiny lump in the center of my palm provided me with elimination of cramped thighs on very hot hike. Additionally, It provides me with a solid source of energy without an up or downer as would a sugary drink. An excellent source of energy and electrolyte.
Water Bottle or Hydration Pack for Backpacking – Hiking Hydration
Whether you’re traveling someplace hot or someplace cold, having an insulated water bottle, like this one from , can really come in handy. While an insulated bottle is slightly heavier than an average bottle, keeping a drink cold for 24 hours or hot for 6 hours is well worth the extra weight. Just think about walking around Paris in the fall and having hot coffee with you for hours, snowboarding in Colorado and having hot hot chocolate in your pack, or hiking in the summer and having ice cold water with you the whole time. And the best part, this double-walled, vacuum insulated, stainless steel bottle (which comes in 12, 16 and 20 oz. sizes) has a slim profile, allowing it to easily fit in most car’s cup holders and backpack’s water bottle holsters. Cost: $29.95
The Top 10 Best Filtered Water Bottles for Hiking, 2017 - Travelsauro
A water bottle capacity should coincide with the length or duration of the hiking activity. Most water bottles have the capacity to hold 16-32 ounces (1/2-1 liter). For physical activity, it is essential to drink more water than normal to stay hydrated.
Portable Water Bottle With Filter for Travel, Hiking, or Everyday Use