In the warmer months when you set out for a long 3-5 hour ride on the bike you are limited to what you can bring with you: two or three bottles, some gels, a bar, and some cash to stop at a convenient store for a snack. Ultimately, however, your options are limited by space. Riding on the trainer means that you have constant access to whatever happens to be at hand in the fridge or pantry. It’s tempting to have a slice of pie or eat a bowl of ice cream halfway through a long trainer ride –I’ve even contemplated cracking a beer while on the trainer.
While it seems tantalizing to mow down on a steak while riding the trainer, it might not be the best idea. The reason why those little gel packets are, well, gels is because they are easily digested during periods of extended physical activity. This is not to say that you should have to consume gels while on the trainer, but you should try to keep your on-the-bike diet similar to what you would have on the road: easily digestible and packed with carbs. My favourite on the bike snack is dried cranberries. They aren’t particularly substantial but they are packed full of sugar. I like to eat a teaspoonful of dried cranberries between every work interval (assuming the rest interval is longer than 3-5 minutes) and I do this towards the latter part of the rest interval. At the very start of the rest interval I eat two Breton style crackers. They’re a great source of carbs and salt and they’re easily digestible. As a treat I keep a stock pile of two-bite caramilk bars on hand. I eat one of those after the end of the second-to-last work interval as a reward (because let’s face it, if you made it that far, you can probably push out one more interval). Before I get on the bike, about 30-40 minutes before, I cook up 1/3 cup of plain quinoa. Cook the quinoa with lots of water so it gets really mushy –it will digest quicker that way. On really long trainer rides sometimes I will stop part way through and have two pieces of bread with jam just to have something a little more substantial.
When it comes to fluids I prefer to have 3 or 4 bottles at hand near the trainer. Although it wouldn’t take much to refill them, and even with 3 bottles you might need to anyway, I much prefer to reduce any reason to get off the trainer and break my groove. I keep one bottle full of water and two full of an electrolyte drink. I find that I need to consume more water on the trainer than I would out on the road because heat dissipation is so much more difficult riding inside even with a good sized fan.
Play around with your ride fuel. Keep it light and simple but experiment with some fun things. Small treats are great to use for rewards and motivation. Do whatever suits you best but try to make sure your on-the-bike food has has a similar nutritional composition to what you would eat when riding outside on the road.