For most of my riding I much prefer a sports drink mix that is just maltodextrin and electrolytes. It has almost no sweetness and tastes much like mildly flavored water. I find the maltodextrin and fructose drinks really sweet and not to my taste.
This made we wonder if for most of my riding (80%) Z2 170 to 200 watts a single source carb was enough. If one can absorb 60g of maltodextrin per hour why add the fructose when my carb requirement for 3hrs in Z2 is lower than that hourly amount?
Obviously for racing or training into Z3 / Z4 / Z5 the added fructose makes sense to boost carb intake into the 90g/Hr region. So for some session train the gut to the higher carb levels and then race like that.
Thoughts?
No real reason to add anything else. Your body can metabolize about 60g of glucose (maltodextrin) in an hour so you’re pushing up against that a little, but if you’re not having gi issues than I’d say you’re fine.
I’m no role model, but I often ride Z2 (or simply “no intensity”) sessions with just water / electrolytes only for 1-2h rides and around 40-50g/h for 3-5h rides. I definitely try to deliver some carbs for long Z2 runs, primarily for my mood management.
Z2 rides won’t demand from you to exercise at your max capacity, so you don’t need to be topped up to your ears with carbs. Therefore, the relevance of your question goes more into the overall caloric balance… If you had managed to start the Z2 with full glycogen storage and assuming your fat oxidation isn’t metabolically compromised, then you’d have multiple hours or riding before you bonk. Then again, overall caloric balance comes in - when do you need to exercise again and how do you prepare for this?
A lot of “ifs”, but I don’t think you need to worry about going above 50-60g/h for Z2 rides, unless you’re doing >20h per week of swim/bike/run and struggle to eat enough in-between.