Hydration: one 750 ml bottle every 1 to 1.5 hours, depending on environmental conditions and effort (i.e. on a hot day, you might need more water).

Electrolytes: make sure you're getting some (tablets, food, drinks), especially if it is a hot day and you're drinking more water

Fuel:

On a ride less than 2 hours ... you probably don't need anything at all, if you've been eating regularly throughout the day. Most of us have ample fuel in storage. If you're going out after work, and you haven't eaten since lunch, you might have a banana before you go.

But you might put a couple granola bars in your handlebar bag ... just in case. Chances are you won't need them, but there might be the occasional ride where you do.


On a ride between about 2 and 4 hours ... eat something before you go out and bring 2 or 3 granola bars with you. At some point after the 1-hour mark, you might assess the situation and decide whether you need to eat a bit.


On a ride over 4 hours, it's not a bad idea to think about fuel a little more seriously. Eat something before you go out, bring some granola bars and maybe a banana or two, and starting about the 1 hour mark, aim to consume 200-300 calories per hour. The fitter you are, the less you need to consume (maybe only 100-200 calories per hour). The longer the ride (i.e. double centuries, 400K randonnees, etc.), the more you might want to try to consume (aiming for around the 300 calorie mark) for as long as you can stomach food.