gg, the world of sports nutrition can be very daunting. I am still experimenting with my nutrition before/during/after workouts, and there are a ton of options.
My favorites:
One bottle plain water, one bottle gatorade (I don't like HEED)
Sport beans (jelly beans)
Cookies (usually chocolate chip with either walnuts or coconut)
Gu (Vanilla flavored)
Balance bars (for really long bike rides where I need some solid food)
I don't like:
HEED
Clif Shot Bloks (for me, they cause a huge glucose spike and then a crash.. I also don't like the flavors or the texture)
PowerBar Gels (they're too watery, I like the thicker Gu)
What I haven't explored extensively:
Other electrolyte/energy drink mixes
HammerGel
Customizable sport drinks
I do think you would benefit from taking a critical look at your hydration and nutrition and experiment a bit, even with your shorter runs. You would probably benefit a lot from a gel or two in the pockets of your waist pack. I try to take in at least 50 calories every 30-60 minutes during extended activity. At my Olympic duathlon last Sunday, I had:
yogurt for breakfast on the drive up (3 hours prior to the start)
plenty of water/gatorade during the two hours before the start
a packet of sport beans 1.5 hours prior to start (30 minutes before the scheduled start, it got delayed)
a Gu 15 minutes before the actual start
stopped once at the water station on the 5k run for a small cup of water
about 30oz of gatorade during my bike ride
a Gu during my bike ride (halfway point)
Half a Gu starting the 10k run
water at 3 water stations during the 10k (miles 1, 3.1, and 5)
The other half of my Gu at the halfway point water station
And nutrition-wise, I felt great when I finished. I have the tendency to "bonk" pretty easily if I am not taking in additional calories during extended exercise, and it takes me days to recover to where I feel right again. If I pay more attention to my nutrition, I don't have anywhere near as much recovery time or soreness.
I will be looking into S-caps if I decide to train for a half-ironman duathlon in August, and I will probably start using them on my longer bike rides as well. Since I sweat a lot, the hardest part is staying hydrated. Running tends to leave me less hydrated than cycling, because I can guzzle a whole bottle of water on the bike without feeling too nauseous.. that's not so possible when I'm jostling around at a run.
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